1e3b3d0f5SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 296fd7ce5SGreg Kroah-Hartman /* 396fd7ce5SGreg Kroah-Hartman * Copyright (C) 1991, 1992 Linus Torvalds 496fd7ce5SGreg Kroah-Hartman */ 596fd7ce5SGreg Kroah-Hartman 696fd7ce5SGreg Kroah-Hartman /* 796fd7ce5SGreg Kroah-Hartman * 'tty_io.c' gives an orthogonal feeling to tty's, be they consoles 896fd7ce5SGreg Kroah-Hartman * or rs-channels. It also implements echoing, cooked mode etc. 996fd7ce5SGreg Kroah-Hartman * 1096fd7ce5SGreg Kroah-Hartman * Kill-line thanks to John T Kohl, who also corrected VMIN = VTIME = 0. 1196fd7ce5SGreg Kroah-Hartman * 1296fd7ce5SGreg Kroah-Hartman * Modified by Theodore Ts'o, 9/14/92, to dynamically allocate the 1396fd7ce5SGreg Kroah-Hartman * tty_struct and tty_queue structures. Previously there was an array 1496fd7ce5SGreg Kroah-Hartman * of 256 tty_struct's which was statically allocated, and the 1596fd7ce5SGreg Kroah-Hartman * tty_queue structures were allocated at boot time. Both are now 1696fd7ce5SGreg Kroah-Hartman * dynamically allocated only when the tty is open. 1796fd7ce5SGreg Kroah-Hartman * 1896fd7ce5SGreg Kroah-Hartman * Also restructured routines so that there is more of a separation 1996fd7ce5SGreg Kroah-Hartman * between the high-level tty routines (tty_io.c and tty_ioctl.c) and 2096fd7ce5SGreg Kroah-Hartman * the low-level tty routines (serial.c, pty.c, console.c). This 2196fd7ce5SGreg Kroah-Hartman * makes for cleaner and more compact code. -TYT, 9/17/92 2296fd7ce5SGreg Kroah-Hartman * 2396fd7ce5SGreg Kroah-Hartman * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines 2496fd7ce5SGreg Kroah-Hartman * which can be dynamically activated and de-activated by the line 2596fd7ce5SGreg Kroah-Hartman * discipline handling modules (like SLIP). 2696fd7ce5SGreg Kroah-Hartman * 2796fd7ce5SGreg Kroah-Hartman * NOTE: pay no attention to the line discipline code (yet); its 2896fd7ce5SGreg Kroah-Hartman * interface is still subject to change in this version... 2996fd7ce5SGreg Kroah-Hartman * -- TYT, 1/31/92 3096fd7ce5SGreg Kroah-Hartman * 3196fd7ce5SGreg Kroah-Hartman * Added functionality to the OPOST tty handling. No delays, but all 3296fd7ce5SGreg Kroah-Hartman * other bits should be there. 3396fd7ce5SGreg Kroah-Hartman * -- Nick Holloway <alfie@dcs.warwick.ac.uk>, 27th May 1993. 3496fd7ce5SGreg Kroah-Hartman * 3596fd7ce5SGreg Kroah-Hartman * Rewrote canonical mode and added more termios flags. 3696fd7ce5SGreg Kroah-Hartman * -- julian@uhunix.uhcc.hawaii.edu (J. Cowley), 13Jan94 3796fd7ce5SGreg Kroah-Hartman * 3896fd7ce5SGreg Kroah-Hartman * Reorganized FASYNC support so mouse code can share it. 3996fd7ce5SGreg Kroah-Hartman * -- ctm@ardi.com, 9Sep95 4096fd7ce5SGreg Kroah-Hartman * 4196fd7ce5SGreg Kroah-Hartman * New TIOCLINUX variants added. 4296fd7ce5SGreg Kroah-Hartman * -- mj@k332.feld.cvut.cz, 19-Nov-95 4396fd7ce5SGreg Kroah-Hartman * 4496fd7ce5SGreg Kroah-Hartman * Restrict vt switching via ioctl() 4596fd7ce5SGreg Kroah-Hartman * -- grif@cs.ucr.edu, 5-Dec-95 4696fd7ce5SGreg Kroah-Hartman * 4796fd7ce5SGreg Kroah-Hartman * Move console and virtual terminal code to more appropriate files, 4896fd7ce5SGreg Kroah-Hartman * implement CONFIG_VT and generalize console device interface. 4996fd7ce5SGreg Kroah-Hartman * -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97 5096fd7ce5SGreg Kroah-Hartman * 5196fd7ce5SGreg Kroah-Hartman * Rewrote tty_init_dev and tty_release_dev to eliminate races. 5296fd7ce5SGreg Kroah-Hartman * -- Bill Hawes <whawes@star.net>, June 97 5396fd7ce5SGreg Kroah-Hartman * 5496fd7ce5SGreg Kroah-Hartman * Added devfs support. 5596fd7ce5SGreg Kroah-Hartman * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 13-Jan-1998 5696fd7ce5SGreg Kroah-Hartman * 5796fd7ce5SGreg Kroah-Hartman * Added support for a Unix98-style ptmx device. 5896fd7ce5SGreg Kroah-Hartman * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 5996fd7ce5SGreg Kroah-Hartman * 6096fd7ce5SGreg Kroah-Hartman * Reduced memory usage for older ARM systems 6196fd7ce5SGreg Kroah-Hartman * -- Russell King <rmk@arm.linux.org.uk> 6296fd7ce5SGreg Kroah-Hartman * 6396fd7ce5SGreg Kroah-Hartman * Move do_SAK() into process context. Less stack use in devfs functions. 6496fd7ce5SGreg Kroah-Hartman * alloc_tty_struct() always uses kmalloc() 6596fd7ce5SGreg Kroah-Hartman * -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01 6696fd7ce5SGreg Kroah-Hartman */ 6796fd7ce5SGreg Kroah-Hartman 6896fd7ce5SGreg Kroah-Hartman #include <linux/types.h> 6996fd7ce5SGreg Kroah-Hartman #include <linux/major.h> 7096fd7ce5SGreg Kroah-Hartman #include <linux/errno.h> 7196fd7ce5SGreg Kroah-Hartman #include <linux/signal.h> 7296fd7ce5SGreg Kroah-Hartman #include <linux/fcntl.h> 733f07c014SIngo Molnar #include <linux/sched/signal.h> 7429930025SIngo Molnar #include <linux/sched/task.h> 7596fd7ce5SGreg Kroah-Hartman #include <linux/interrupt.h> 7696fd7ce5SGreg Kroah-Hartman #include <linux/tty.h> 7796fd7ce5SGreg Kroah-Hartman #include <linux/tty_driver.h> 7896fd7ce5SGreg Kroah-Hartman #include <linux/tty_flip.h> 7996fd7ce5SGreg Kroah-Hartman #include <linux/devpts_fs.h> 8096fd7ce5SGreg Kroah-Hartman #include <linux/file.h> 8196fd7ce5SGreg Kroah-Hartman #include <linux/fdtable.h> 8296fd7ce5SGreg Kroah-Hartman #include <linux/console.h> 8396fd7ce5SGreg Kroah-Hartman #include <linux/timer.h> 8496fd7ce5SGreg Kroah-Hartman #include <linux/ctype.h> 8596fd7ce5SGreg Kroah-Hartman #include <linux/kd.h> 8696fd7ce5SGreg Kroah-Hartman #include <linux/mm.h> 8796fd7ce5SGreg Kroah-Hartman #include <linux/string.h> 8896fd7ce5SGreg Kroah-Hartman #include <linux/slab.h> 8996fd7ce5SGreg Kroah-Hartman #include <linux/poll.h> 9096fd7ce5SGreg Kroah-Hartman #include <linux/proc_fs.h> 9196fd7ce5SGreg Kroah-Hartman #include <linux/init.h> 9296fd7ce5SGreg Kroah-Hartman #include <linux/module.h> 9396fd7ce5SGreg Kroah-Hartman #include <linux/device.h> 9496fd7ce5SGreg Kroah-Hartman #include <linux/wait.h> 9596fd7ce5SGreg Kroah-Hartman #include <linux/bitops.h> 9696fd7ce5SGreg Kroah-Hartman #include <linux/delay.h> 9796fd7ce5SGreg Kroah-Hartman #include <linux/seq_file.h> 9896fd7ce5SGreg Kroah-Hartman #include <linux/serial.h> 995a3c6b25SManuel Zerpies #include <linux/ratelimit.h> 100e2112038SAl Viro #include <linux/compat.h> 10196fd7ce5SGreg Kroah-Hartman 10296fd7ce5SGreg Kroah-Hartman #include <linux/uaccess.h> 10396fd7ce5SGreg Kroah-Hartman 10496fd7ce5SGreg Kroah-Hartman #include <linux/kbd_kern.h> 10596fd7ce5SGreg Kroah-Hartman #include <linux/vt_kern.h> 10696fd7ce5SGreg Kroah-Hartman #include <linux/selection.h> 10796fd7ce5SGreg Kroah-Hartman 10896fd7ce5SGreg Kroah-Hartman #include <linux/kmod.h> 10996fd7ce5SGreg Kroah-Hartman #include <linux/nsproxy.h> 11096fd7ce5SGreg Kroah-Hartman 11196fd7ce5SGreg Kroah-Hartman #undef TTY_DEBUG_HANGUP 112accff793SPeter Hurley #ifdef TTY_DEBUG_HANGUP 113accff793SPeter Hurley # define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args) 114accff793SPeter Hurley #else 115accff793SPeter Hurley # define tty_debug_hangup(tty, f, args...) do { } while (0) 116accff793SPeter Hurley #endif 11796fd7ce5SGreg Kroah-Hartman 11896fd7ce5SGreg Kroah-Hartman #define TTY_PARANOIA_CHECK 1 11996fd7ce5SGreg Kroah-Hartman #define CHECK_TTY_COUNT 1 12096fd7ce5SGreg Kroah-Hartman 12196fd7ce5SGreg Kroah-Hartman struct ktermios tty_std_termios = { /* for the benefit of tty drivers */ 12296fd7ce5SGreg Kroah-Hartman .c_iflag = ICRNL | IXON, 12396fd7ce5SGreg Kroah-Hartman .c_oflag = OPOST | ONLCR, 12496fd7ce5SGreg Kroah-Hartman .c_cflag = B38400 | CS8 | CREAD | HUPCL, 12596fd7ce5SGreg Kroah-Hartman .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | 12696fd7ce5SGreg Kroah-Hartman ECHOCTL | ECHOKE | IEXTEN, 12796fd7ce5SGreg Kroah-Hartman .c_cc = INIT_C_CC, 12896fd7ce5SGreg Kroah-Hartman .c_ispeed = 38400, 129133b1306SPeter Hurley .c_ospeed = 38400, 130133b1306SPeter Hurley /* .c_line = N_TTY, */ 13196fd7ce5SGreg Kroah-Hartman }; 13296fd7ce5SGreg Kroah-Hartman 13396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_std_termios); 13496fd7ce5SGreg Kroah-Hartman 13596fd7ce5SGreg Kroah-Hartman /* This list gets poked at by procfs and various bits of boot up code. This 13696fd7ce5SGreg Kroah-Hartman could do with some rationalisation such as pulling the tty proc function 13796fd7ce5SGreg Kroah-Hartman into this file */ 13896fd7ce5SGreg Kroah-Hartman 13996fd7ce5SGreg Kroah-Hartman LIST_HEAD(tty_drivers); /* linked list of tty drivers */ 14096fd7ce5SGreg Kroah-Hartman 141d1d027efSPeter Hurley /* Mutex to protect creating and releasing a tty */ 14296fd7ce5SGreg Kroah-Hartman DEFINE_MUTEX(tty_mutex); 14396fd7ce5SGreg Kroah-Hartman 14496fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); 14596fd7ce5SGreg Kroah-Hartman static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *); 14696fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *, const char __user *, 14796fd7ce5SGreg Kroah-Hartman size_t, loff_t *); 148afc9a42bSAl Viro static __poll_t tty_poll(struct file *, poll_table *); 14996fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *, struct file *); 15096fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 15196fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 15296fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 15396fd7ce5SGreg Kroah-Hartman unsigned long arg); 15496fd7ce5SGreg Kroah-Hartman #else 15596fd7ce5SGreg Kroah-Hartman #define tty_compat_ioctl NULL 15696fd7ce5SGreg Kroah-Hartman #endif 15796fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on); 15896fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on); 15996fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx); 16096fd7ce5SGreg Kroah-Hartman 16196fd7ce5SGreg Kroah-Hartman /** 16296fd7ce5SGreg Kroah-Hartman * free_tty_struct - free a disused tty 16396fd7ce5SGreg Kroah-Hartman * @tty: tty struct to free 16496fd7ce5SGreg Kroah-Hartman * 16596fd7ce5SGreg Kroah-Hartman * Free the write buffers, tty queue and tty memory itself. 16696fd7ce5SGreg Kroah-Hartman * 16796fd7ce5SGreg Kroah-Hartman * Locking: none. Must be called after tty is definitely unused 16896fd7ce5SGreg Kroah-Hartman */ 16996fd7ce5SGreg Kroah-Hartman 170a3123fd0SPeter Hurley static void free_tty_struct(struct tty_struct *tty) 17196fd7ce5SGreg Kroah-Hartman { 172c8b710b3SPeter Hurley tty_ldisc_deinit(tty); 17396fd7ce5SGreg Kroah-Hartman put_device(tty->dev); 17496fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 17589c8d91eSAlan Cox tty->magic = 0xDEADDEAD; 17696fd7ce5SGreg Kroah-Hartman kfree(tty); 17796fd7ce5SGreg Kroah-Hartman } 17896fd7ce5SGreg Kroah-Hartman 17996fd7ce5SGreg Kroah-Hartman static inline struct tty_struct *file_tty(struct file *file) 18096fd7ce5SGreg Kroah-Hartman { 18196fd7ce5SGreg Kroah-Hartman return ((struct tty_file_private *)file->private_data)->tty; 18296fd7ce5SGreg Kroah-Hartman } 18396fd7ce5SGreg Kroah-Hartman 184fa90e1c9SJiri Slaby int tty_alloc_file(struct file *file) 18596fd7ce5SGreg Kroah-Hartman { 18696fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 18796fd7ce5SGreg Kroah-Hartman 18896fd7ce5SGreg Kroah-Hartman priv = kmalloc(sizeof(*priv), GFP_KERNEL); 18996fd7ce5SGreg Kroah-Hartman if (!priv) 19096fd7ce5SGreg Kroah-Hartman return -ENOMEM; 19196fd7ce5SGreg Kroah-Hartman 192fa90e1c9SJiri Slaby file->private_data = priv; 193fa90e1c9SJiri Slaby 194fa90e1c9SJiri Slaby return 0; 195fa90e1c9SJiri Slaby } 196fa90e1c9SJiri Slaby 197fa90e1c9SJiri Slaby /* Associate a new file with the tty structure */ 198fa90e1c9SJiri Slaby void tty_add_file(struct tty_struct *tty, struct file *file) 199fa90e1c9SJiri Slaby { 200fa90e1c9SJiri Slaby struct tty_file_private *priv = file->private_data; 201fa90e1c9SJiri Slaby 20296fd7ce5SGreg Kroah-Hartman priv->tty = tty; 20396fd7ce5SGreg Kroah-Hartman priv->file = file; 20496fd7ce5SGreg Kroah-Hartman 2054a510969SPeter Hurley spin_lock(&tty->files_lock); 20696fd7ce5SGreg Kroah-Hartman list_add(&priv->list, &tty->tty_files); 2074a510969SPeter Hurley spin_unlock(&tty->files_lock); 208fa90e1c9SJiri Slaby } 20996fd7ce5SGreg Kroah-Hartman 210fa90e1c9SJiri Slaby /** 211fa90e1c9SJiri Slaby * tty_free_file - free file->private_data 212fa90e1c9SJiri Slaby * 213fa90e1c9SJiri Slaby * This shall be used only for fail path handling when tty_add_file was not 214fa90e1c9SJiri Slaby * called yet. 215fa90e1c9SJiri Slaby */ 216fa90e1c9SJiri Slaby void tty_free_file(struct file *file) 217fa90e1c9SJiri Slaby { 218fa90e1c9SJiri Slaby struct tty_file_private *priv = file->private_data; 219fa90e1c9SJiri Slaby 220fa90e1c9SJiri Slaby file->private_data = NULL; 221fa90e1c9SJiri Slaby kfree(priv); 22296fd7ce5SGreg Kroah-Hartman } 22396fd7ce5SGreg Kroah-Hartman 22496fd7ce5SGreg Kroah-Hartman /* Delete file from its tty */ 2252520e274SJosh Triplett static void tty_del_file(struct file *file) 22696fd7ce5SGreg Kroah-Hartman { 22796fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv = file->private_data; 2284a510969SPeter Hurley struct tty_struct *tty = priv->tty; 22996fd7ce5SGreg Kroah-Hartman 2304a510969SPeter Hurley spin_lock(&tty->files_lock); 23196fd7ce5SGreg Kroah-Hartman list_del(&priv->list); 2324a510969SPeter Hurley spin_unlock(&tty->files_lock); 233fa90e1c9SJiri Slaby tty_free_file(file); 23496fd7ce5SGreg Kroah-Hartman } 23596fd7ce5SGreg Kroah-Hartman 23696fd7ce5SGreg Kroah-Hartman /** 23796fd7ce5SGreg Kroah-Hartman * tty_name - return tty naming 23896fd7ce5SGreg Kroah-Hartman * @tty: tty structure 23996fd7ce5SGreg Kroah-Hartman * 24096fd7ce5SGreg Kroah-Hartman * Convert a tty structure into a name. The name reflects the kernel 24196fd7ce5SGreg Kroah-Hartman * naming policy and if udev is in use may not reflect user space 24296fd7ce5SGreg Kroah-Hartman * 24396fd7ce5SGreg Kroah-Hartman * Locking: none 24496fd7ce5SGreg Kroah-Hartman */ 24596fd7ce5SGreg Kroah-Hartman 246429b4749SRasmus Villemoes const char *tty_name(const struct tty_struct *tty) 24796fd7ce5SGreg Kroah-Hartman { 24896fd7ce5SGreg Kroah-Hartman if (!tty) /* Hmm. NULL pointer. That's fun. */ 249917162c9SRasmus Villemoes return "NULL tty"; 250917162c9SRasmus Villemoes return tty->name; 25196fd7ce5SGreg Kroah-Hartman } 25296fd7ce5SGreg Kroah-Hartman 25396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_name); 25496fd7ce5SGreg Kroah-Hartman 2550a083eddSPeter Hurley const char *tty_driver_name(const struct tty_struct *tty) 2560a083eddSPeter Hurley { 2570a083eddSPeter Hurley if (!tty || !tty->driver) 2580a083eddSPeter Hurley return ""; 2590a083eddSPeter Hurley return tty->driver->name; 2600a083eddSPeter Hurley } 2610a083eddSPeter Hurley 26282b8f888SPeter Hurley static int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 26396fd7ce5SGreg Kroah-Hartman const char *routine) 26496fd7ce5SGreg Kroah-Hartman { 26596fd7ce5SGreg Kroah-Hartman #ifdef TTY_PARANOIA_CHECK 26696fd7ce5SGreg Kroah-Hartman if (!tty) { 26789222e62SPeter Hurley pr_warn("(%d:%d): %s: NULL tty\n", 26896fd7ce5SGreg Kroah-Hartman imajor(inode), iminor(inode), routine); 26996fd7ce5SGreg Kroah-Hartman return 1; 27096fd7ce5SGreg Kroah-Hartman } 27196fd7ce5SGreg Kroah-Hartman if (tty->magic != TTY_MAGIC) { 27289222e62SPeter Hurley pr_warn("(%d:%d): %s: bad magic number\n", 27396fd7ce5SGreg Kroah-Hartman imajor(inode), iminor(inode), routine); 27496fd7ce5SGreg Kroah-Hartman return 1; 27596fd7ce5SGreg Kroah-Hartman } 27696fd7ce5SGreg Kroah-Hartman #endif 27796fd7ce5SGreg Kroah-Hartman return 0; 27896fd7ce5SGreg Kroah-Hartman } 27996fd7ce5SGreg Kroah-Hartman 280deb287e7SPeter Hurley /* Caller must hold tty_lock */ 28196fd7ce5SGreg Kroah-Hartman static int check_tty_count(struct tty_struct *tty, const char *routine) 28296fd7ce5SGreg Kroah-Hartman { 28396fd7ce5SGreg Kroah-Hartman #ifdef CHECK_TTY_COUNT 28496fd7ce5SGreg Kroah-Hartman struct list_head *p; 285a09ac397SOkash Khawaja int count = 0, kopen_count = 0; 28696fd7ce5SGreg Kroah-Hartman 2874a510969SPeter Hurley spin_lock(&tty->files_lock); 28896fd7ce5SGreg Kroah-Hartman list_for_each(p, &tty->tty_files) { 28996fd7ce5SGreg Kroah-Hartman count++; 29096fd7ce5SGreg Kroah-Hartman } 2914a510969SPeter Hurley spin_unlock(&tty->files_lock); 29296fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 29396fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_SLAVE && 29496fd7ce5SGreg Kroah-Hartman tty->link && tty->link->count) 29596fd7ce5SGreg Kroah-Hartman count++; 296a09ac397SOkash Khawaja if (tty_port_kopened(tty->port)) 297a09ac397SOkash Khawaja kopen_count++; 298a09ac397SOkash Khawaja if (tty->count != (count + kopen_count)) { 299a09ac397SOkash Khawaja tty_warn(tty, "%s: tty->count(%d) != (#fd's(%d) + #kopen's(%d))\n", 300a09ac397SOkash Khawaja routine, tty->count, count, kopen_count); 301a09ac397SOkash Khawaja return (count + kopen_count); 30296fd7ce5SGreg Kroah-Hartman } 30396fd7ce5SGreg Kroah-Hartman #endif 30496fd7ce5SGreg Kroah-Hartman return 0; 30596fd7ce5SGreg Kroah-Hartman } 30696fd7ce5SGreg Kroah-Hartman 30796fd7ce5SGreg Kroah-Hartman /** 30896fd7ce5SGreg Kroah-Hartman * get_tty_driver - find device of a tty 30996fd7ce5SGreg Kroah-Hartman * @dev_t: device identifier 31096fd7ce5SGreg Kroah-Hartman * @index: returns the index of the tty 31196fd7ce5SGreg Kroah-Hartman * 31296fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a device number 31396fd7ce5SGreg Kroah-Hartman * and also passes back the index number. 31496fd7ce5SGreg Kroah-Hartman * 31596fd7ce5SGreg Kroah-Hartman * Locking: caller must hold tty_mutex 31696fd7ce5SGreg Kroah-Hartman */ 31796fd7ce5SGreg Kroah-Hartman 31896fd7ce5SGreg Kroah-Hartman static struct tty_driver *get_tty_driver(dev_t device, int *index) 31996fd7ce5SGreg Kroah-Hartman { 32096fd7ce5SGreg Kroah-Hartman struct tty_driver *p; 32196fd7ce5SGreg Kroah-Hartman 32296fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 32396fd7ce5SGreg Kroah-Hartman dev_t base = MKDEV(p->major, p->minor_start); 32496fd7ce5SGreg Kroah-Hartman if (device < base || device >= base + p->num) 32596fd7ce5SGreg Kroah-Hartman continue; 32696fd7ce5SGreg Kroah-Hartman *index = device - base; 32796fd7ce5SGreg Kroah-Hartman return tty_driver_kref_get(p); 32896fd7ce5SGreg Kroah-Hartman } 32996fd7ce5SGreg Kroah-Hartman return NULL; 33096fd7ce5SGreg Kroah-Hartman } 33196fd7ce5SGreg Kroah-Hartman 332fc61ed51SOkash Khawaja /** 333fc61ed51SOkash Khawaja * tty_dev_name_to_number - return dev_t for device name 334fc61ed51SOkash Khawaja * @name: user space name of device under /dev 335fc61ed51SOkash Khawaja * @number: pointer to dev_t that this function will populate 336fc61ed51SOkash Khawaja * 337fc61ed51SOkash Khawaja * This function converts device names like ttyS0 or ttyUSB1 into dev_t 338fc61ed51SOkash Khawaja * like (4, 64) or (188, 1). If no corresponding driver is registered then 339fc61ed51SOkash Khawaja * the function returns -ENODEV. 340fc61ed51SOkash Khawaja * 341fc61ed51SOkash Khawaja * Locking: this acquires tty_mutex to protect the tty_drivers list from 342fc61ed51SOkash Khawaja * being modified while we are traversing it, and makes sure to 343fc61ed51SOkash Khawaja * release it before exiting. 344fc61ed51SOkash Khawaja */ 345fc61ed51SOkash Khawaja int tty_dev_name_to_number(const char *name, dev_t *number) 346fc61ed51SOkash Khawaja { 347fc61ed51SOkash Khawaja struct tty_driver *p; 348fc61ed51SOkash Khawaja int ret; 349fc61ed51SOkash Khawaja int index, prefix_length = 0; 350fc61ed51SOkash Khawaja const char *str; 351fc61ed51SOkash Khawaja 352fc61ed51SOkash Khawaja for (str = name; *str && !isdigit(*str); str++) 353fc61ed51SOkash Khawaja ; 354fc61ed51SOkash Khawaja 355fc61ed51SOkash Khawaja if (!*str) 356fc61ed51SOkash Khawaja return -EINVAL; 357fc61ed51SOkash Khawaja 358fc61ed51SOkash Khawaja ret = kstrtoint(str, 10, &index); 359fc61ed51SOkash Khawaja if (ret) 360fc61ed51SOkash Khawaja return ret; 361fc61ed51SOkash Khawaja 362fc61ed51SOkash Khawaja prefix_length = str - name; 363fc61ed51SOkash Khawaja mutex_lock(&tty_mutex); 364fc61ed51SOkash Khawaja 365fc61ed51SOkash Khawaja list_for_each_entry(p, &tty_drivers, tty_drivers) 366fc61ed51SOkash Khawaja if (prefix_length == strlen(p->name) && strncmp(name, 367fc61ed51SOkash Khawaja p->name, prefix_length) == 0) { 368fc61ed51SOkash Khawaja if (index < p->num) { 369fc61ed51SOkash Khawaja *number = MKDEV(p->major, p->minor_start + index); 370fc61ed51SOkash Khawaja goto out; 371fc61ed51SOkash Khawaja } 372fc61ed51SOkash Khawaja } 373fc61ed51SOkash Khawaja 374fc61ed51SOkash Khawaja /* if here then driver wasn't found */ 375fc61ed51SOkash Khawaja ret = -ENODEV; 376fc61ed51SOkash Khawaja out: 377fc61ed51SOkash Khawaja mutex_unlock(&tty_mutex); 378fc61ed51SOkash Khawaja return ret; 379fc61ed51SOkash Khawaja } 380fc61ed51SOkash Khawaja EXPORT_SYMBOL_GPL(tty_dev_name_to_number); 381fc61ed51SOkash Khawaja 38296fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_CONSOLE_POLL 38396fd7ce5SGreg Kroah-Hartman 38496fd7ce5SGreg Kroah-Hartman /** 38596fd7ce5SGreg Kroah-Hartman * tty_find_polling_driver - find device of a polled tty 38696fd7ce5SGreg Kroah-Hartman * @name: name string to match 38796fd7ce5SGreg Kroah-Hartman * @line: pointer to resulting tty line nr 38896fd7ce5SGreg Kroah-Hartman * 38996fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a name 39096fd7ce5SGreg Kroah-Hartman * and the condition that the tty driver is capable of polled 39196fd7ce5SGreg Kroah-Hartman * operation. 39296fd7ce5SGreg Kroah-Hartman */ 39396fd7ce5SGreg Kroah-Hartman struct tty_driver *tty_find_polling_driver(char *name, int *line) 39496fd7ce5SGreg Kroah-Hartman { 39596fd7ce5SGreg Kroah-Hartman struct tty_driver *p, *res = NULL; 39696fd7ce5SGreg Kroah-Hartman int tty_line = 0; 39796fd7ce5SGreg Kroah-Hartman int len; 39896fd7ce5SGreg Kroah-Hartman char *str, *stp; 39996fd7ce5SGreg Kroah-Hartman 40096fd7ce5SGreg Kroah-Hartman for (str = name; *str; str++) 40196fd7ce5SGreg Kroah-Hartman if ((*str >= '0' && *str <= '9') || *str == ',') 40296fd7ce5SGreg Kroah-Hartman break; 40396fd7ce5SGreg Kroah-Hartman if (!*str) 40496fd7ce5SGreg Kroah-Hartman return NULL; 40596fd7ce5SGreg Kroah-Hartman 40696fd7ce5SGreg Kroah-Hartman len = str - name; 40796fd7ce5SGreg Kroah-Hartman tty_line = simple_strtoul(str, &str, 10); 40896fd7ce5SGreg Kroah-Hartman 40996fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 41096fd7ce5SGreg Kroah-Hartman /* Search through the tty devices to look for a match */ 41196fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 41233a1a7beSMiles Chen if (!len || strncmp(name, p->name, len) != 0) 41396fd7ce5SGreg Kroah-Hartman continue; 41496fd7ce5SGreg Kroah-Hartman stp = str; 41596fd7ce5SGreg Kroah-Hartman if (*stp == ',') 41696fd7ce5SGreg Kroah-Hartman stp++; 41796fd7ce5SGreg Kroah-Hartman if (*stp == '\0') 41896fd7ce5SGreg Kroah-Hartman stp = NULL; 41996fd7ce5SGreg Kroah-Hartman 42096fd7ce5SGreg Kroah-Hartman if (tty_line >= 0 && tty_line < p->num && p->ops && 42196fd7ce5SGreg Kroah-Hartman p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { 42296fd7ce5SGreg Kroah-Hartman res = tty_driver_kref_get(p); 42396fd7ce5SGreg Kroah-Hartman *line = tty_line; 42496fd7ce5SGreg Kroah-Hartman break; 42596fd7ce5SGreg Kroah-Hartman } 42696fd7ce5SGreg Kroah-Hartman } 42796fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 42896fd7ce5SGreg Kroah-Hartman 42996fd7ce5SGreg Kroah-Hartman return res; 43096fd7ce5SGreg Kroah-Hartman } 43196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_find_polling_driver); 43296fd7ce5SGreg Kroah-Hartman #endif 43396fd7ce5SGreg Kroah-Hartman 43496fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_read(struct file *file, char __user *buf, 43596fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 43696fd7ce5SGreg Kroah-Hartman { 43796fd7ce5SGreg Kroah-Hartman return 0; 43896fd7ce5SGreg Kroah-Hartman } 43996fd7ce5SGreg Kroah-Hartman 44096fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, 44196fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 44296fd7ce5SGreg Kroah-Hartman { 44396fd7ce5SGreg Kroah-Hartman return -EIO; 44496fd7ce5SGreg Kroah-Hartman } 44596fd7ce5SGreg Kroah-Hartman 44696fd7ce5SGreg Kroah-Hartman /* No kernel lock held - none needed ;) */ 447afc9a42bSAl Viro static __poll_t hung_up_tty_poll(struct file *filp, poll_table *wait) 44896fd7ce5SGreg Kroah-Hartman { 449a9a08845SLinus Torvalds return EPOLLIN | EPOLLOUT | EPOLLERR | EPOLLHUP | EPOLLRDNORM | EPOLLWRNORM; 45096fd7ce5SGreg Kroah-Hartman } 45196fd7ce5SGreg Kroah-Hartman 45296fd7ce5SGreg Kroah-Hartman static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, 45396fd7ce5SGreg Kroah-Hartman unsigned long arg) 45496fd7ce5SGreg Kroah-Hartman { 45596fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 45696fd7ce5SGreg Kroah-Hartman } 45796fd7ce5SGreg Kroah-Hartman 45896fd7ce5SGreg Kroah-Hartman static long hung_up_tty_compat_ioctl(struct file *file, 45996fd7ce5SGreg Kroah-Hartman unsigned int cmd, unsigned long arg) 46096fd7ce5SGreg Kroah-Hartman { 46196fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 46296fd7ce5SGreg Kroah-Hartman } 46396fd7ce5SGreg Kroah-Hartman 464f557474cSPeter Hurley static int hung_up_tty_fasync(int fd, struct file *file, int on) 465f557474cSPeter Hurley { 466f557474cSPeter Hurley return -ENOTTY; 467f557474cSPeter Hurley } 468f557474cSPeter Hurley 469d01c3289SMasatake YAMATO static void tty_show_fdinfo(struct seq_file *m, struct file *file) 470d01c3289SMasatake YAMATO { 471d01c3289SMasatake YAMATO struct tty_struct *tty = file_tty(file); 472d01c3289SMasatake YAMATO 473d01c3289SMasatake YAMATO if (tty && tty->ops && tty->ops->show_fdinfo) 474d01c3289SMasatake YAMATO tty->ops->show_fdinfo(tty, m); 475d01c3289SMasatake YAMATO } 476d01c3289SMasatake YAMATO 47796fd7ce5SGreg Kroah-Hartman static const struct file_operations tty_fops = { 47896fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 47996fd7ce5SGreg Kroah-Hartman .read = tty_read, 48096fd7ce5SGreg Kroah-Hartman .write = tty_write, 48196fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 48296fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 48396fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 48496fd7ce5SGreg Kroah-Hartman .open = tty_open, 48596fd7ce5SGreg Kroah-Hartman .release = tty_release, 48696fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 487d01c3289SMasatake YAMATO .show_fdinfo = tty_show_fdinfo, 48896fd7ce5SGreg Kroah-Hartman }; 48996fd7ce5SGreg Kroah-Hartman 49096fd7ce5SGreg Kroah-Hartman static const struct file_operations console_fops = { 49196fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 49296fd7ce5SGreg Kroah-Hartman .read = tty_read, 49396fd7ce5SGreg Kroah-Hartman .write = redirected_tty_write, 49496fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 49596fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 49696fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 49796fd7ce5SGreg Kroah-Hartman .open = tty_open, 49896fd7ce5SGreg Kroah-Hartman .release = tty_release, 49996fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 50096fd7ce5SGreg Kroah-Hartman }; 50196fd7ce5SGreg Kroah-Hartman 50296fd7ce5SGreg Kroah-Hartman static const struct file_operations hung_up_tty_fops = { 50396fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 50496fd7ce5SGreg Kroah-Hartman .read = hung_up_tty_read, 50596fd7ce5SGreg Kroah-Hartman .write = hung_up_tty_write, 50696fd7ce5SGreg Kroah-Hartman .poll = hung_up_tty_poll, 50796fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = hung_up_tty_ioctl, 50896fd7ce5SGreg Kroah-Hartman .compat_ioctl = hung_up_tty_compat_ioctl, 50996fd7ce5SGreg Kroah-Hartman .release = tty_release, 510f557474cSPeter Hurley .fasync = hung_up_tty_fasync, 51196fd7ce5SGreg Kroah-Hartman }; 51296fd7ce5SGreg Kroah-Hartman 51396fd7ce5SGreg Kroah-Hartman static DEFINE_SPINLOCK(redirect_lock); 51496fd7ce5SGreg Kroah-Hartman static struct file *redirect; 51596fd7ce5SGreg Kroah-Hartman 51696fd7ce5SGreg Kroah-Hartman /** 51796fd7ce5SGreg Kroah-Hartman * tty_wakeup - request more data 51896fd7ce5SGreg Kroah-Hartman * @tty: terminal 51996fd7ce5SGreg Kroah-Hartman * 52096fd7ce5SGreg Kroah-Hartman * Internal and external helper for wakeups of tty. This function 52196fd7ce5SGreg Kroah-Hartman * informs the line discipline if present that the driver is ready 52296fd7ce5SGreg Kroah-Hartman * to receive more output data. 52396fd7ce5SGreg Kroah-Hartman */ 52496fd7ce5SGreg Kroah-Hartman 52596fd7ce5SGreg Kroah-Hartman void tty_wakeup(struct tty_struct *tty) 52696fd7ce5SGreg Kroah-Hartman { 52796fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 52896fd7ce5SGreg Kroah-Hartman 52996fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { 53096fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref(tty); 53196fd7ce5SGreg Kroah-Hartman if (ld) { 53296fd7ce5SGreg Kroah-Hartman if (ld->ops->write_wakeup) 53396fd7ce5SGreg Kroah-Hartman ld->ops->write_wakeup(tty); 53496fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 53596fd7ce5SGreg Kroah-Hartman } 53696fd7ce5SGreg Kroah-Hartman } 537a9a08845SLinus Torvalds wake_up_interruptible_poll(&tty->write_wait, EPOLLOUT); 53896fd7ce5SGreg Kroah-Hartman } 53996fd7ce5SGreg Kroah-Hartman 54096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_wakeup); 54196fd7ce5SGreg Kroah-Hartman 54296fd7ce5SGreg Kroah-Hartman /** 54396fd7ce5SGreg Kroah-Hartman * __tty_hangup - actual handler for hangup events 54496fd7ce5SGreg Kroah-Hartman * @work: tty device 54596fd7ce5SGreg Kroah-Hartman * 546ef4f527cSKevin Cernekee * This can be called by a "kworker" kernel thread. That is process 54796fd7ce5SGreg Kroah-Hartman * synchronous but doesn't hold any locks, so we need to make sure we 54896fd7ce5SGreg Kroah-Hartman * have the appropriate locks for what we're doing. 54996fd7ce5SGreg Kroah-Hartman * 55096fd7ce5SGreg Kroah-Hartman * The hangup event clears any pending redirections onto the hung up 55196fd7ce5SGreg Kroah-Hartman * device. It ensures future writes will error and it does the needed 55296fd7ce5SGreg Kroah-Hartman * line discipline hangup and signal delivery. The tty object itself 55396fd7ce5SGreg Kroah-Hartman * remains intact. 55496fd7ce5SGreg Kroah-Hartman * 55596fd7ce5SGreg Kroah-Hartman * Locking: 55696fd7ce5SGreg Kroah-Hartman * BTM 55796fd7ce5SGreg Kroah-Hartman * redirect lock for undoing redirection 55896fd7ce5SGreg Kroah-Hartman * file list lock for manipulating list of ttys 559137084bbSPeter Hurley * tty_ldiscs_lock from called functions 5606a1c0680SPeter Hurley * termios_rwsem resetting termios data 56196fd7ce5SGreg Kroah-Hartman * tasklist_lock to walk task list for hangup event 56296fd7ce5SGreg Kroah-Hartman * ->siglock to protect ->signal/->sighand 56396fd7ce5SGreg Kroah-Hartman */ 564f91e2590SPeter Hurley static void __tty_hangup(struct tty_struct *tty, int exit_session) 56596fd7ce5SGreg Kroah-Hartman { 56696fd7ce5SGreg Kroah-Hartman struct file *cons_filp = NULL; 56796fd7ce5SGreg Kroah-Hartman struct file *filp, *f = NULL; 56896fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 56996fd7ce5SGreg Kroah-Hartman int closecount = 0, n; 570ea648a47SPeter Hurley int refs; 57196fd7ce5SGreg Kroah-Hartman 57296fd7ce5SGreg Kroah-Hartman if (!tty) 57396fd7ce5SGreg Kroah-Hartman return; 57496fd7ce5SGreg Kroah-Hartman 57596fd7ce5SGreg Kroah-Hartman 57696fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 57796fd7ce5SGreg Kroah-Hartman if (redirect && file_tty(redirect) == tty) { 57896fd7ce5SGreg Kroah-Hartman f = redirect; 57996fd7ce5SGreg Kroah-Hartman redirect = NULL; 58096fd7ce5SGreg Kroah-Hartman } 58196fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 58296fd7ce5SGreg Kroah-Hartman 58389c8d91eSAlan Cox tty_lock(tty); 58496fd7ce5SGreg Kroah-Hartman 585cb50e523SPeter Hurley if (test_bit(TTY_HUPPED, &tty->flags)) { 586cb50e523SPeter Hurley tty_unlock(tty); 587cb50e523SPeter Hurley return; 588cb50e523SPeter Hurley } 589cb50e523SPeter Hurley 59028b0f8a6STejun Heo /* 59128b0f8a6STejun Heo * Some console devices aren't actually hung up for technical and 59228b0f8a6STejun Heo * historical reasons, which can lead to indefinite interruptible 59328b0f8a6STejun Heo * sleep in n_tty_read(). The following explicitly tells 59428b0f8a6STejun Heo * n_tty_read() to abort readers. 59528b0f8a6STejun Heo */ 59628b0f8a6STejun Heo set_bit(TTY_HUPPING, &tty->flags); 59728b0f8a6STejun Heo 59896fd7ce5SGreg Kroah-Hartman /* inuse_filps is protected by the single tty lock, 59996fd7ce5SGreg Kroah-Hartman this really needs to change if we want to flush the 60096fd7ce5SGreg Kroah-Hartman workqueue with the lock held */ 60196fd7ce5SGreg Kroah-Hartman check_tty_count(tty, "tty_hangup"); 60296fd7ce5SGreg Kroah-Hartman 6034a510969SPeter Hurley spin_lock(&tty->files_lock); 60496fd7ce5SGreg Kroah-Hartman /* This breaks for file handles being sent over AF_UNIX sockets ? */ 60596fd7ce5SGreg Kroah-Hartman list_for_each_entry(priv, &tty->tty_files, list) { 60696fd7ce5SGreg Kroah-Hartman filp = priv->file; 60796fd7ce5SGreg Kroah-Hartman if (filp->f_op->write == redirected_tty_write) 60896fd7ce5SGreg Kroah-Hartman cons_filp = filp; 60996fd7ce5SGreg Kroah-Hartman if (filp->f_op->write != tty_write) 61096fd7ce5SGreg Kroah-Hartman continue; 61196fd7ce5SGreg Kroah-Hartman closecount++; 61296fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); /* can't block */ 61396fd7ce5SGreg Kroah-Hartman filp->f_op = &hung_up_tty_fops; 61496fd7ce5SGreg Kroah-Hartman } 6154a510969SPeter Hurley spin_unlock(&tty->files_lock); 61696fd7ce5SGreg Kroah-Hartman 61725fdf243SPeter Hurley refs = tty_signal_session_leader(tty, exit_session); 61825fdf243SPeter Hurley /* Account for the p->signal references we killed */ 61925fdf243SPeter Hurley while (refs--) 62025fdf243SPeter Hurley tty_kref_put(tty); 62125fdf243SPeter Hurley 622892d1fa7SPeter Hurley tty_ldisc_hangup(tty, cons_filp != NULL); 62396fd7ce5SGreg Kroah-Hartman 62420cc225bSPeter Hurley spin_lock_irq(&tty->ctrl_lock); 62596fd7ce5SGreg Kroah-Hartman clear_bit(TTY_THROTTLED, &tty->flags); 62696fd7ce5SGreg Kroah-Hartman clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 62796fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 62896fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 62996fd7ce5SGreg Kroah-Hartman tty->session = NULL; 63096fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 63196fd7ce5SGreg Kroah-Hartman tty->ctrl_status = 0; 63220cc225bSPeter Hurley spin_unlock_irq(&tty->ctrl_lock); 63396fd7ce5SGreg Kroah-Hartman 63496fd7ce5SGreg Kroah-Hartman /* 63596fd7ce5SGreg Kroah-Hartman * If one of the devices matches a console pointer, we 63696fd7ce5SGreg Kroah-Hartman * cannot just call hangup() because that will cause 63796fd7ce5SGreg Kroah-Hartman * tty->count and state->count to go out of sync. 63896fd7ce5SGreg Kroah-Hartman * So we just call close() the right number of times. 63996fd7ce5SGreg Kroah-Hartman */ 64096fd7ce5SGreg Kroah-Hartman if (cons_filp) { 64196fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 64296fd7ce5SGreg Kroah-Hartman for (n = 0; n < closecount; n++) 64396fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, cons_filp); 64496fd7ce5SGreg Kroah-Hartman } else if (tty->ops->hangup) 6457c6d340fSPeter Hurley tty->ops->hangup(tty); 64696fd7ce5SGreg Kroah-Hartman /* 647892d1fa7SPeter Hurley * We don't want to have driver/ldisc interactions beyond the ones 648892d1fa7SPeter Hurley * we did here. The driver layer expects no calls after ->hangup() 649892d1fa7SPeter Hurley * from the ldisc side, which is now guaranteed. 65096fd7ce5SGreg Kroah-Hartman */ 65196fd7ce5SGreg Kroah-Hartman set_bit(TTY_HUPPED, &tty->flags); 65228b0f8a6STejun Heo clear_bit(TTY_HUPPING, &tty->flags); 65389c8d91eSAlan Cox tty_unlock(tty); 65496fd7ce5SGreg Kroah-Hartman 65596fd7ce5SGreg Kroah-Hartman if (f) 65696fd7ce5SGreg Kroah-Hartman fput(f); 65796fd7ce5SGreg Kroah-Hartman } 65896fd7ce5SGreg Kroah-Hartman 65996fd7ce5SGreg Kroah-Hartman static void do_tty_hangup(struct work_struct *work) 66096fd7ce5SGreg Kroah-Hartman { 66196fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 66296fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 66396fd7ce5SGreg Kroah-Hartman 664f91e2590SPeter Hurley __tty_hangup(tty, 0); 66596fd7ce5SGreg Kroah-Hartman } 66696fd7ce5SGreg Kroah-Hartman 66796fd7ce5SGreg Kroah-Hartman /** 66896fd7ce5SGreg Kroah-Hartman * tty_hangup - trigger a hangup event 66996fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 67096fd7ce5SGreg Kroah-Hartman * 67196fd7ce5SGreg Kroah-Hartman * A carrier loss (virtual or otherwise) has occurred on this like 67296fd7ce5SGreg Kroah-Hartman * schedule a hangup sequence to run after this event. 67396fd7ce5SGreg Kroah-Hartman */ 67496fd7ce5SGreg Kroah-Hartman 67596fd7ce5SGreg Kroah-Hartman void tty_hangup(struct tty_struct *tty) 67696fd7ce5SGreg Kroah-Hartman { 677d435cefeSPeter Hurley tty_debug_hangup(tty, "hangup\n"); 67896fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 67996fd7ce5SGreg Kroah-Hartman } 68096fd7ce5SGreg Kroah-Hartman 68196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hangup); 68296fd7ce5SGreg Kroah-Hartman 68396fd7ce5SGreg Kroah-Hartman /** 68496fd7ce5SGreg Kroah-Hartman * tty_vhangup - process vhangup 68596fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 68696fd7ce5SGreg Kroah-Hartman * 68796fd7ce5SGreg Kroah-Hartman * The user has asked via system call for the terminal to be hung up. 68896fd7ce5SGreg Kroah-Hartman * We do this synchronously so that when the syscall returns the process 68996fd7ce5SGreg Kroah-Hartman * is complete. That guarantee is necessary for security reasons. 69096fd7ce5SGreg Kroah-Hartman */ 69196fd7ce5SGreg Kroah-Hartman 69296fd7ce5SGreg Kroah-Hartman void tty_vhangup(struct tty_struct *tty) 69396fd7ce5SGreg Kroah-Hartman { 694d435cefeSPeter Hurley tty_debug_hangup(tty, "vhangup\n"); 695f91e2590SPeter Hurley __tty_hangup(tty, 0); 69696fd7ce5SGreg Kroah-Hartman } 69796fd7ce5SGreg Kroah-Hartman 69896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_vhangup); 69996fd7ce5SGreg Kroah-Hartman 70096fd7ce5SGreg Kroah-Hartman 70196fd7ce5SGreg Kroah-Hartman /** 70296fd7ce5SGreg Kroah-Hartman * tty_vhangup_self - process vhangup for own ctty 70396fd7ce5SGreg Kroah-Hartman * 70496fd7ce5SGreg Kroah-Hartman * Perform a vhangup on the current controlling tty 70596fd7ce5SGreg Kroah-Hartman */ 70696fd7ce5SGreg Kroah-Hartman 70796fd7ce5SGreg Kroah-Hartman void tty_vhangup_self(void) 70896fd7ce5SGreg Kroah-Hartman { 70996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 71096fd7ce5SGreg Kroah-Hartman 71196fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 71296fd7ce5SGreg Kroah-Hartman if (tty) { 71396fd7ce5SGreg Kroah-Hartman tty_vhangup(tty); 71496fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 71596fd7ce5SGreg Kroah-Hartman } 71696fd7ce5SGreg Kroah-Hartman } 71796fd7ce5SGreg Kroah-Hartman 71896fd7ce5SGreg Kroah-Hartman /** 719f91e2590SPeter Hurley * tty_vhangup_session - hangup session leader exit 720f91e2590SPeter Hurley * @tty: tty to hangup 721f91e2590SPeter Hurley * 722f91e2590SPeter Hurley * The session leader is exiting and hanging up its controlling terminal. 723f91e2590SPeter Hurley * Every process in the foreground process group is signalled SIGHUP. 724f91e2590SPeter Hurley * 725f91e2590SPeter Hurley * We do this synchronously so that when the syscall returns the process 726f91e2590SPeter Hurley * is complete. That guarantee is necessary for security reasons. 727f91e2590SPeter Hurley */ 728f91e2590SPeter Hurley 729a1235b3eSNicolas Pitre void tty_vhangup_session(struct tty_struct *tty) 730f91e2590SPeter Hurley { 731d435cefeSPeter Hurley tty_debug_hangup(tty, "session hangup\n"); 732f91e2590SPeter Hurley __tty_hangup(tty, 1); 733f91e2590SPeter Hurley } 734f91e2590SPeter Hurley 735f91e2590SPeter Hurley /** 73696fd7ce5SGreg Kroah-Hartman * tty_hung_up_p - was tty hung up 73796fd7ce5SGreg Kroah-Hartman * @filp: file pointer of tty 73896fd7ce5SGreg Kroah-Hartman * 73996fd7ce5SGreg Kroah-Hartman * Return true if the tty has been subject to a vhangup or a carrier 74096fd7ce5SGreg Kroah-Hartman * loss 74196fd7ce5SGreg Kroah-Hartman */ 74296fd7ce5SGreg Kroah-Hartman 74396fd7ce5SGreg Kroah-Hartman int tty_hung_up_p(struct file *filp) 74496fd7ce5SGreg Kroah-Hartman { 745ed3f0af8SAlan Cox return (filp && filp->f_op == &hung_up_tty_fops); 74696fd7ce5SGreg Kroah-Hartman } 74796fd7ce5SGreg Kroah-Hartman 74896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hung_up_p); 74996fd7ce5SGreg Kroah-Hartman 75096fd7ce5SGreg Kroah-Hartman /** 75196fd7ce5SGreg Kroah-Hartman * stop_tty - propagate flow control 75296fd7ce5SGreg Kroah-Hartman * @tty: tty to stop 75396fd7ce5SGreg Kroah-Hartman * 75401adc807SPeter Hurley * Perform flow control to the driver. May be called 75596fd7ce5SGreg Kroah-Hartman * on an already stopped device and will not re-call the driver 75696fd7ce5SGreg Kroah-Hartman * method. 75796fd7ce5SGreg Kroah-Hartman * 75896fd7ce5SGreg Kroah-Hartman * This functionality is used by both the line disciplines for 75996fd7ce5SGreg Kroah-Hartman * halting incoming flow and by the driver. It may therefore be 76096fd7ce5SGreg Kroah-Hartman * called from any context, may be under the tty atomic_write_lock 76196fd7ce5SGreg Kroah-Hartman * but not always. 76296fd7ce5SGreg Kroah-Hartman * 76396fd7ce5SGreg Kroah-Hartman * Locking: 764f9e053dcSPeter Hurley * flow_lock 76596fd7ce5SGreg Kroah-Hartman */ 76696fd7ce5SGreg Kroah-Hartman 767f9e053dcSPeter Hurley void __stop_tty(struct tty_struct *tty) 76896fd7ce5SGreg Kroah-Hartman { 769f9e053dcSPeter Hurley if (tty->stopped) 77096fd7ce5SGreg Kroah-Hartman return; 77196fd7ce5SGreg Kroah-Hartman tty->stopped = 1; 77296fd7ce5SGreg Kroah-Hartman if (tty->ops->stop) 773c961bfb1SPeter Hurley tty->ops->stop(tty); 77496fd7ce5SGreg Kroah-Hartman } 77596fd7ce5SGreg Kroah-Hartman 776f9e053dcSPeter Hurley void stop_tty(struct tty_struct *tty) 777f9e053dcSPeter Hurley { 778f9e053dcSPeter Hurley unsigned long flags; 779f9e053dcSPeter Hurley 780f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 781f9e053dcSPeter Hurley __stop_tty(tty); 782f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 783f9e053dcSPeter Hurley } 78496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(stop_tty); 78596fd7ce5SGreg Kroah-Hartman 78696fd7ce5SGreg Kroah-Hartman /** 78796fd7ce5SGreg Kroah-Hartman * start_tty - propagate flow control 78896fd7ce5SGreg Kroah-Hartman * @tty: tty to start 78996fd7ce5SGreg Kroah-Hartman * 79001adc807SPeter Hurley * Start a tty that has been stopped if at all possible. If this 79101adc807SPeter Hurley * tty was previous stopped and is now being started, the driver 79201adc807SPeter Hurley * start method is invoked and the line discipline woken. 79396fd7ce5SGreg Kroah-Hartman * 79496fd7ce5SGreg Kroah-Hartman * Locking: 795f9e053dcSPeter Hurley * flow_lock 79696fd7ce5SGreg Kroah-Hartman */ 79796fd7ce5SGreg Kroah-Hartman 798f9e053dcSPeter Hurley void __start_tty(struct tty_struct *tty) 79996fd7ce5SGreg Kroah-Hartman { 800f9e053dcSPeter Hurley if (!tty->stopped || tty->flow_stopped) 80196fd7ce5SGreg Kroah-Hartman return; 80296fd7ce5SGreg Kroah-Hartman tty->stopped = 0; 80396fd7ce5SGreg Kroah-Hartman if (tty->ops->start) 804c961bfb1SPeter Hurley tty->ops->start(tty); 80596fd7ce5SGreg Kroah-Hartman tty_wakeup(tty); 80696fd7ce5SGreg Kroah-Hartman } 80796fd7ce5SGreg Kroah-Hartman 808f9e053dcSPeter Hurley void start_tty(struct tty_struct *tty) 809f9e053dcSPeter Hurley { 810f9e053dcSPeter Hurley unsigned long flags; 811f9e053dcSPeter Hurley 812f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 813f9e053dcSPeter Hurley __start_tty(tty); 814f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 815f9e053dcSPeter Hurley } 81696fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(start_tty); 81796fd7ce5SGreg Kroah-Hartman 818c884f871SArnd Bergmann static void tty_update_time(struct timespec64 *time) 81937b7f3c7SJiri Slaby { 820c884f871SArnd Bergmann time64_t sec = ktime_get_real_seconds(); 821fbf47635SGreg Kroah-Hartman 822fbf47635SGreg Kroah-Hartman /* 823fbf47635SGreg Kroah-Hartman * We only care if the two values differ in anything other than the 824fbf47635SGreg Kroah-Hartman * lower three bits (i.e every 8 seconds). If so, then we can update 825fbf47635SGreg Kroah-Hartman * the time of the tty device, otherwise it could be construded as a 826fbf47635SGreg Kroah-Hartman * security leak to let userspace know the exact timing of the tty. 827fbf47635SGreg Kroah-Hartman */ 828fbf47635SGreg Kroah-Hartman if ((sec ^ time->tv_sec) & ~7) 82937b7f3c7SJiri Slaby time->tv_sec = sec; 83037b7f3c7SJiri Slaby } 83137b7f3c7SJiri Slaby 83296fd7ce5SGreg Kroah-Hartman /** 83396fd7ce5SGreg Kroah-Hartman * tty_read - read method for tty device files 83496fd7ce5SGreg Kroah-Hartman * @file: pointer to tty file 83596fd7ce5SGreg Kroah-Hartman * @buf: user buffer 83696fd7ce5SGreg Kroah-Hartman * @count: size of user buffer 83796fd7ce5SGreg Kroah-Hartman * @ppos: unused 83896fd7ce5SGreg Kroah-Hartman * 83996fd7ce5SGreg Kroah-Hartman * Perform the read system call function on this terminal device. Checks 84096fd7ce5SGreg Kroah-Hartman * for hung up devices before calling the line discipline method. 84196fd7ce5SGreg Kroah-Hartman * 84296fd7ce5SGreg Kroah-Hartman * Locking: 84396fd7ce5SGreg Kroah-Hartman * Locks the line discipline internally while needed. Multiple 84496fd7ce5SGreg Kroah-Hartman * read calls may be outstanding in parallel. 84596fd7ce5SGreg Kroah-Hartman */ 84696fd7ce5SGreg Kroah-Hartman 84796fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *file, char __user *buf, size_t count, 84896fd7ce5SGreg Kroah-Hartman loff_t *ppos) 84996fd7ce5SGreg Kroah-Hartman { 85096fd7ce5SGreg Kroah-Hartman int i; 85137b7f3c7SJiri Slaby struct inode *inode = file_inode(file); 85296fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 85396fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 85496fd7ce5SGreg Kroah-Hartman 85537b7f3c7SJiri Slaby if (tty_paranoia_check(tty, inode, "tty_read")) 85696fd7ce5SGreg Kroah-Hartman return -EIO; 85718900ca6SPeter Hurley if (!tty || tty_io_error(tty)) 85896fd7ce5SGreg Kroah-Hartman return -EIO; 85996fd7ce5SGreg Kroah-Hartman 86096fd7ce5SGreg Kroah-Hartman /* We want to wait for the line discipline to sort out in this 86196fd7ce5SGreg Kroah-Hartman situation */ 86296fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 863e55afd11SPeter Hurley if (!ld) 864e55afd11SPeter Hurley return hung_up_tty_read(file, buf, count, ppos); 86596fd7ce5SGreg Kroah-Hartman if (ld->ops->read) 866c961bfb1SPeter Hurley i = ld->ops->read(tty, file, buf, count); 86796fd7ce5SGreg Kroah-Hartman else 86896fd7ce5SGreg Kroah-Hartman i = -EIO; 86996fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 870b0de59b5SJiri Slaby 871c884f871SArnd Bergmann if (i > 0) 872c884f871SArnd Bergmann tty_update_time(&inode->i_atime); 87337b7f3c7SJiri Slaby 87496fd7ce5SGreg Kroah-Hartman return i; 87596fd7ce5SGreg Kroah-Hartman } 87696fd7ce5SGreg Kroah-Hartman 877136d5258SPeter Hurley static void tty_write_unlock(struct tty_struct *tty) 87896fd7ce5SGreg Kroah-Hartman { 87996fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty->atomic_write_lock); 880a9a08845SLinus Torvalds wake_up_interruptible_poll(&tty->write_wait, EPOLLOUT); 88196fd7ce5SGreg Kroah-Hartman } 88296fd7ce5SGreg Kroah-Hartman 883136d5258SPeter Hurley static int tty_write_lock(struct tty_struct *tty, int ndelay) 88496fd7ce5SGreg Kroah-Hartman { 88596fd7ce5SGreg Kroah-Hartman if (!mutex_trylock(&tty->atomic_write_lock)) { 88696fd7ce5SGreg Kroah-Hartman if (ndelay) 88796fd7ce5SGreg Kroah-Hartman return -EAGAIN; 88896fd7ce5SGreg Kroah-Hartman if (mutex_lock_interruptible(&tty->atomic_write_lock)) 88996fd7ce5SGreg Kroah-Hartman return -ERESTARTSYS; 89096fd7ce5SGreg Kroah-Hartman } 89196fd7ce5SGreg Kroah-Hartman return 0; 89296fd7ce5SGreg Kroah-Hartman } 89396fd7ce5SGreg Kroah-Hartman 89496fd7ce5SGreg Kroah-Hartman /* 89596fd7ce5SGreg Kroah-Hartman * Split writes up in sane blocksizes to avoid 89696fd7ce5SGreg Kroah-Hartman * denial-of-service type attacks 89796fd7ce5SGreg Kroah-Hartman */ 89896fd7ce5SGreg Kroah-Hartman static inline ssize_t do_tty_write( 89996fd7ce5SGreg Kroah-Hartman ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), 90096fd7ce5SGreg Kroah-Hartman struct tty_struct *tty, 90196fd7ce5SGreg Kroah-Hartman struct file *file, 90296fd7ce5SGreg Kroah-Hartman const char __user *buf, 90396fd7ce5SGreg Kroah-Hartman size_t count) 90496fd7ce5SGreg Kroah-Hartman { 90596fd7ce5SGreg Kroah-Hartman ssize_t ret, written = 0; 90696fd7ce5SGreg Kroah-Hartman unsigned int chunk; 90796fd7ce5SGreg Kroah-Hartman 90896fd7ce5SGreg Kroah-Hartman ret = tty_write_lock(tty, file->f_flags & O_NDELAY); 90996fd7ce5SGreg Kroah-Hartman if (ret < 0) 91096fd7ce5SGreg Kroah-Hartman return ret; 91196fd7ce5SGreg Kroah-Hartman 91296fd7ce5SGreg Kroah-Hartman /* 91396fd7ce5SGreg Kroah-Hartman * We chunk up writes into a temporary buffer. This 91496fd7ce5SGreg Kroah-Hartman * simplifies low-level drivers immensely, since they 91596fd7ce5SGreg Kroah-Hartman * don't have locking issues and user mode accesses. 91696fd7ce5SGreg Kroah-Hartman * 91796fd7ce5SGreg Kroah-Hartman * But if TTY_NO_WRITE_SPLIT is set, we should use a 91896fd7ce5SGreg Kroah-Hartman * big chunk-size.. 91996fd7ce5SGreg Kroah-Hartman * 92096fd7ce5SGreg Kroah-Hartman * The default chunk-size is 2kB, because the NTTY 92196fd7ce5SGreg Kroah-Hartman * layer has problems with bigger chunks. It will 92296fd7ce5SGreg Kroah-Hartman * claim to be able to handle more characters than 92396fd7ce5SGreg Kroah-Hartman * it actually does. 92496fd7ce5SGreg Kroah-Hartman * 92596fd7ce5SGreg Kroah-Hartman * FIXME: This can probably go away now except that 64K chunks 92696fd7ce5SGreg Kroah-Hartman * are too likely to fail unless switched to vmalloc... 92796fd7ce5SGreg Kroah-Hartman */ 92896fd7ce5SGreg Kroah-Hartman chunk = 2048; 92996fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) 93096fd7ce5SGreg Kroah-Hartman chunk = 65536; 93196fd7ce5SGreg Kroah-Hartman if (count < chunk) 93296fd7ce5SGreg Kroah-Hartman chunk = count; 93396fd7ce5SGreg Kroah-Hartman 93496fd7ce5SGreg Kroah-Hartman /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ 93596fd7ce5SGreg Kroah-Hartman if (tty->write_cnt < chunk) { 93696fd7ce5SGreg Kroah-Hartman unsigned char *buf_chunk; 93796fd7ce5SGreg Kroah-Hartman 93896fd7ce5SGreg Kroah-Hartman if (chunk < 1024) 93996fd7ce5SGreg Kroah-Hartman chunk = 1024; 94096fd7ce5SGreg Kroah-Hartman 94196fd7ce5SGreg Kroah-Hartman buf_chunk = kmalloc(chunk, GFP_KERNEL); 94296fd7ce5SGreg Kroah-Hartman if (!buf_chunk) { 94396fd7ce5SGreg Kroah-Hartman ret = -ENOMEM; 94496fd7ce5SGreg Kroah-Hartman goto out; 94596fd7ce5SGreg Kroah-Hartman } 94696fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 94796fd7ce5SGreg Kroah-Hartman tty->write_cnt = chunk; 94896fd7ce5SGreg Kroah-Hartman tty->write_buf = buf_chunk; 94996fd7ce5SGreg Kroah-Hartman } 95096fd7ce5SGreg Kroah-Hartman 95196fd7ce5SGreg Kroah-Hartman /* Do the write .. */ 95296fd7ce5SGreg Kroah-Hartman for (;;) { 95396fd7ce5SGreg Kroah-Hartman size_t size = count; 95496fd7ce5SGreg Kroah-Hartman if (size > chunk) 95596fd7ce5SGreg Kroah-Hartman size = chunk; 95696fd7ce5SGreg Kroah-Hartman ret = -EFAULT; 95796fd7ce5SGreg Kroah-Hartman if (copy_from_user(tty->write_buf, buf, size)) 95896fd7ce5SGreg Kroah-Hartman break; 95996fd7ce5SGreg Kroah-Hartman ret = write(tty, file, tty->write_buf, size); 96096fd7ce5SGreg Kroah-Hartman if (ret <= 0) 96196fd7ce5SGreg Kroah-Hartman break; 96296fd7ce5SGreg Kroah-Hartman written += ret; 96396fd7ce5SGreg Kroah-Hartman buf += ret; 96496fd7ce5SGreg Kroah-Hartman count -= ret; 96596fd7ce5SGreg Kroah-Hartman if (!count) 96696fd7ce5SGreg Kroah-Hartman break; 96796fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 96896fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 96996fd7ce5SGreg Kroah-Hartman break; 97096fd7ce5SGreg Kroah-Hartman cond_resched(); 97196fd7ce5SGreg Kroah-Hartman } 97237b7f3c7SJiri Slaby if (written) { 973c884f871SArnd Bergmann tty_update_time(&file_inode(file)->i_mtime); 97496fd7ce5SGreg Kroah-Hartman ret = written; 97537b7f3c7SJiri Slaby } 97696fd7ce5SGreg Kroah-Hartman out: 97796fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 97896fd7ce5SGreg Kroah-Hartman return ret; 97996fd7ce5SGreg Kroah-Hartman } 98096fd7ce5SGreg Kroah-Hartman 98196fd7ce5SGreg Kroah-Hartman /** 98296fd7ce5SGreg Kroah-Hartman * tty_write_message - write a message to a certain tty, not just the console. 98396fd7ce5SGreg Kroah-Hartman * @tty: the destination tty_struct 98496fd7ce5SGreg Kroah-Hartman * @msg: the message to write 98596fd7ce5SGreg Kroah-Hartman * 98696fd7ce5SGreg Kroah-Hartman * This is used for messages that need to be redirected to a specific tty. 98796fd7ce5SGreg Kroah-Hartman * We don't put it into the syslog queue right now maybe in the future if 98896fd7ce5SGreg Kroah-Hartman * really needed. 98996fd7ce5SGreg Kroah-Hartman * 99096fd7ce5SGreg Kroah-Hartman * We must still hold the BTM and test the CLOSING flag for the moment. 99196fd7ce5SGreg Kroah-Hartman */ 99296fd7ce5SGreg Kroah-Hartman 99396fd7ce5SGreg Kroah-Hartman void tty_write_message(struct tty_struct *tty, char *msg) 99496fd7ce5SGreg Kroah-Hartman { 99596fd7ce5SGreg Kroah-Hartman if (tty) { 99696fd7ce5SGreg Kroah-Hartman mutex_lock(&tty->atomic_write_lock); 99789c8d91eSAlan Cox tty_lock(tty); 9984b41b953SPeter Hurley if (tty->ops->write && tty->count > 0) 99996fd7ce5SGreg Kroah-Hartman tty->ops->write(tty, msg, strlen(msg)); 100089c8d91eSAlan Cox tty_unlock(tty); 100196fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 100296fd7ce5SGreg Kroah-Hartman } 100396fd7ce5SGreg Kroah-Hartman return; 100496fd7ce5SGreg Kroah-Hartman } 100596fd7ce5SGreg Kroah-Hartman 100696fd7ce5SGreg Kroah-Hartman 100796fd7ce5SGreg Kroah-Hartman /** 100896fd7ce5SGreg Kroah-Hartman * tty_write - write method for tty device file 100996fd7ce5SGreg Kroah-Hartman * @file: tty file pointer 101096fd7ce5SGreg Kroah-Hartman * @buf: user data to write 101196fd7ce5SGreg Kroah-Hartman * @count: bytes to write 101296fd7ce5SGreg Kroah-Hartman * @ppos: unused 101396fd7ce5SGreg Kroah-Hartman * 101496fd7ce5SGreg Kroah-Hartman * Write data to a tty device via the line discipline. 101596fd7ce5SGreg Kroah-Hartman * 101696fd7ce5SGreg Kroah-Hartman * Locking: 101796fd7ce5SGreg Kroah-Hartman * Locks the line discipline as required 101896fd7ce5SGreg Kroah-Hartman * Writes to the tty driver are serialized by the atomic_write_lock 101996fd7ce5SGreg Kroah-Hartman * and are then processed in chunks to the device. The line discipline 102096fd7ce5SGreg Kroah-Hartman * write method will not be invoked in parallel for each device. 102196fd7ce5SGreg Kroah-Hartman */ 102296fd7ce5SGreg Kroah-Hartman 102396fd7ce5SGreg Kroah-Hartman static ssize_t tty_write(struct file *file, const char __user *buf, 102496fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 102596fd7ce5SGreg Kroah-Hartman { 102696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 102796fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 102896fd7ce5SGreg Kroah-Hartman ssize_t ret; 102996fd7ce5SGreg Kroah-Hartman 10306131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_write")) 103196fd7ce5SGreg Kroah-Hartman return -EIO; 103218900ca6SPeter Hurley if (!tty || !tty->ops->write || tty_io_error(tty)) 103396fd7ce5SGreg Kroah-Hartman return -EIO; 103496fd7ce5SGreg Kroah-Hartman /* Short term debug to catch buggy drivers */ 103596fd7ce5SGreg Kroah-Hartman if (tty->ops->write_room == NULL) 1036339f36baSPeter Hurley tty_err(tty, "missing write_room method\n"); 103796fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 1038e55afd11SPeter Hurley if (!ld) 1039e55afd11SPeter Hurley return hung_up_tty_write(file, buf, count, ppos); 104096fd7ce5SGreg Kroah-Hartman if (!ld->ops->write) 104196fd7ce5SGreg Kroah-Hartman ret = -EIO; 104296fd7ce5SGreg Kroah-Hartman else 104396fd7ce5SGreg Kroah-Hartman ret = do_tty_write(ld->ops->write, tty, file, buf, count); 104496fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 104596fd7ce5SGreg Kroah-Hartman return ret; 104696fd7ce5SGreg Kroah-Hartman } 104796fd7ce5SGreg Kroah-Hartman 104896fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *file, const char __user *buf, 104996fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 105096fd7ce5SGreg Kroah-Hartman { 105196fd7ce5SGreg Kroah-Hartman struct file *p = NULL; 105296fd7ce5SGreg Kroah-Hartman 105396fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 1054cb0942b8SAl Viro if (redirect) 1055cb0942b8SAl Viro p = get_file(redirect); 105696fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 105796fd7ce5SGreg Kroah-Hartman 105896fd7ce5SGreg Kroah-Hartman if (p) { 105996fd7ce5SGreg Kroah-Hartman ssize_t res; 106096fd7ce5SGreg Kroah-Hartman res = vfs_write(p, buf, count, &p->f_pos); 106196fd7ce5SGreg Kroah-Hartman fput(p); 106296fd7ce5SGreg Kroah-Hartman return res; 106396fd7ce5SGreg Kroah-Hartman } 106496fd7ce5SGreg Kroah-Hartman return tty_write(file, buf, count, ppos); 106596fd7ce5SGreg Kroah-Hartman } 106696fd7ce5SGreg Kroah-Hartman 1067136d5258SPeter Hurley /** 1068136d5258SPeter Hurley * tty_send_xchar - send priority character 1069136d5258SPeter Hurley * 1070136d5258SPeter Hurley * Send a high priority character to the tty even if stopped 1071136d5258SPeter Hurley * 1072136d5258SPeter Hurley * Locking: none for xchar method, write ordering for write method. 1073136d5258SPeter Hurley */ 1074136d5258SPeter Hurley 1075136d5258SPeter Hurley int tty_send_xchar(struct tty_struct *tty, char ch) 1076136d5258SPeter Hurley { 1077136d5258SPeter Hurley int was_stopped = tty->stopped; 1078136d5258SPeter Hurley 1079136d5258SPeter Hurley if (tty->ops->send_xchar) { 1080ee0c1a65SPeter Hurley down_read(&tty->termios_rwsem); 1081136d5258SPeter Hurley tty->ops->send_xchar(tty, ch); 1082ee0c1a65SPeter Hurley up_read(&tty->termios_rwsem); 1083136d5258SPeter Hurley return 0; 1084136d5258SPeter Hurley } 1085136d5258SPeter Hurley 1086136d5258SPeter Hurley if (tty_write_lock(tty, 0) < 0) 1087136d5258SPeter Hurley return -ERESTARTSYS; 1088136d5258SPeter Hurley 1089ee0c1a65SPeter Hurley down_read(&tty->termios_rwsem); 1090136d5258SPeter Hurley if (was_stopped) 1091136d5258SPeter Hurley start_tty(tty); 1092136d5258SPeter Hurley tty->ops->write(tty, &ch, 1); 1093136d5258SPeter Hurley if (was_stopped) 1094136d5258SPeter Hurley stop_tty(tty); 1095ee0c1a65SPeter Hurley up_read(&tty->termios_rwsem); 1096136d5258SPeter Hurley tty_write_unlock(tty); 1097136d5258SPeter Hurley return 0; 1098136d5258SPeter Hurley } 1099136d5258SPeter Hurley 110096fd7ce5SGreg Kroah-Hartman static char ptychar[] = "pqrstuvwxyzabcde"; 110196fd7ce5SGreg Kroah-Hartman 110296fd7ce5SGreg Kroah-Hartman /** 110396fd7ce5SGreg Kroah-Hartman * pty_line_name - generate name for a pty 110496fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 110596fd7ce5SGreg Kroah-Hartman * @index: the minor number 110696fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 6 bytes 110796fd7ce5SGreg Kroah-Hartman * 110896fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 110996fd7ce5SGreg Kroah-Hartman * buffer. 111096fd7ce5SGreg Kroah-Hartman * 111196fd7ce5SGreg Kroah-Hartman * Locking: None 111296fd7ce5SGreg Kroah-Hartman */ 111396fd7ce5SGreg Kroah-Hartman static void pty_line_name(struct tty_driver *driver, int index, char *p) 111496fd7ce5SGreg Kroah-Hartman { 111596fd7ce5SGreg Kroah-Hartman int i = index + driver->name_base; 111696fd7ce5SGreg Kroah-Hartman /* ->name is initialized to "ttyp", but "tty" is expected */ 111796fd7ce5SGreg Kroah-Hartman sprintf(p, "%s%c%x", 111896fd7ce5SGreg Kroah-Hartman driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, 111996fd7ce5SGreg Kroah-Hartman ptychar[i >> 4 & 0xf], i & 0xf); 112096fd7ce5SGreg Kroah-Hartman } 112196fd7ce5SGreg Kroah-Hartman 112296fd7ce5SGreg Kroah-Hartman /** 112396fd7ce5SGreg Kroah-Hartman * tty_line_name - generate name for a tty 112496fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 112596fd7ce5SGreg Kroah-Hartman * @index: the minor number 112696fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 7 bytes 112796fd7ce5SGreg Kroah-Hartman * 112896fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 11295c0a2450SGreg Kroah-Hartman * buffer. 113096fd7ce5SGreg Kroah-Hartman * 113196fd7ce5SGreg Kroah-Hartman * Locking: None 113296fd7ce5SGreg Kroah-Hartman */ 1133723abd87SHannes Reinecke static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p) 113496fd7ce5SGreg Kroah-Hartman { 11350019b408SJiri Slaby if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE) 1136723abd87SHannes Reinecke return sprintf(p, "%s", driver->name); 11370019b408SJiri Slaby else 1138723abd87SHannes Reinecke return sprintf(p, "%s%d", driver->name, 1139723abd87SHannes Reinecke index + driver->name_base); 114096fd7ce5SGreg Kroah-Hartman } 114196fd7ce5SGreg Kroah-Hartman 114296fd7ce5SGreg Kroah-Hartman /** 114396fd7ce5SGreg Kroah-Hartman * tty_driver_lookup_tty() - find an existing tty, if any 114496fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 114596fd7ce5SGreg Kroah-Hartman * @idx: the minor number 114696fd7ce5SGreg Kroah-Hartman * 1147aa3cb814SPeter Hurley * Return the tty, if found. If not found, return NULL or ERR_PTR() if the 1148aa3cb814SPeter Hurley * driver lookup() method returns an error. 114996fd7ce5SGreg Kroah-Hartman * 1150aa3cb814SPeter Hurley * Locking: tty_mutex must be held. If the tty is found, bump the tty kref. 115196fd7ce5SGreg Kroah-Hartman */ 115296fd7ce5SGreg Kroah-Hartman static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, 11538ead9dd5SLinus Torvalds struct file *file, int idx) 115496fd7ce5SGreg Kroah-Hartman { 1155aa3cb814SPeter Hurley struct tty_struct *tty; 115696fd7ce5SGreg Kroah-Hartman 1157aa3cb814SPeter Hurley if (driver->ops->lookup) 115812e84c71SOkash Khawaja if (!file) 115912e84c71SOkash Khawaja tty = ERR_PTR(-EIO); 116012e84c71SOkash Khawaja else 11618ead9dd5SLinus Torvalds tty = driver->ops->lookup(driver, file, idx); 1162aa3cb814SPeter Hurley else 1163aa3cb814SPeter Hurley tty = driver->ttys[idx]; 1164aa3cb814SPeter Hurley 1165aa3cb814SPeter Hurley if (!IS_ERR(tty)) 1166aa3cb814SPeter Hurley tty_kref_get(tty); 1167aa3cb814SPeter Hurley return tty; 116896fd7ce5SGreg Kroah-Hartman } 116996fd7ce5SGreg Kroah-Hartman 117096fd7ce5SGreg Kroah-Hartman /** 117196fd7ce5SGreg Kroah-Hartman * tty_init_termios - helper for termios setup 117296fd7ce5SGreg Kroah-Hartman * @tty: the tty to set up 117396fd7ce5SGreg Kroah-Hartman * 117496fd7ce5SGreg Kroah-Hartman * Initialise the termios structures for this tty. Thus runs under 117596fd7ce5SGreg Kroah-Hartman * the tty_mutex currently so we can be relaxed about ordering. 117696fd7ce5SGreg Kroah-Hartman */ 117796fd7ce5SGreg Kroah-Hartman 1178a3123fd0SPeter Hurley void tty_init_termios(struct tty_struct *tty) 117996fd7ce5SGreg Kroah-Hartman { 118096fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 118196fd7ce5SGreg Kroah-Hartman int idx = tty->index; 118296fd7ce5SGreg Kroah-Hartman 118336b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 118436b3c070SAlan Cox tty->termios = tty->driver->init_termios; 118536b3c070SAlan Cox else { 118636b3c070SAlan Cox /* Check for lazy saved data */ 118796fd7ce5SGreg Kroah-Hartman tp = tty->driver->termios[idx]; 1188ece53405SPeter Hurley if (tp != NULL) { 1189adc8d746SAlan Cox tty->termios = *tp; 1190ece53405SPeter Hurley tty->termios.c_line = tty->driver->init_termios.c_line; 1191ece53405SPeter Hurley } else 119236b3c070SAlan Cox tty->termios = tty->driver->init_termios; 119336b3c070SAlan Cox } 119496fd7ce5SGreg Kroah-Hartman /* Compatibility until drivers always set this */ 1195adc8d746SAlan Cox tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios); 1196adc8d746SAlan Cox tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios); 119796fd7ce5SGreg Kroah-Hartman } 119896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_init_termios); 119996fd7ce5SGreg Kroah-Hartman 120066d450e8SJiri Slaby int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty) 120166d450e8SJiri Slaby { 1202a3123fd0SPeter Hurley tty_init_termios(tty); 120366d450e8SJiri Slaby tty_driver_kref_get(driver); 120466d450e8SJiri Slaby tty->count++; 120566d450e8SJiri Slaby driver->ttys[tty->index] = tty; 120666d450e8SJiri Slaby return 0; 120766d450e8SJiri Slaby } 120866d450e8SJiri Slaby EXPORT_SYMBOL_GPL(tty_standard_install); 120966d450e8SJiri Slaby 121096fd7ce5SGreg Kroah-Hartman /** 121196fd7ce5SGreg Kroah-Hartman * tty_driver_install_tty() - install a tty entry in the driver 121296fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 121396fd7ce5SGreg Kroah-Hartman * @tty: the tty 121496fd7ce5SGreg Kroah-Hartman * 121596fd7ce5SGreg Kroah-Hartman * Install a tty object into the driver tables. The tty->index field 121696fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. This method is responsible 121796fd7ce5SGreg Kroah-Hartman * for ensuring any need additional structures are allocated and 121896fd7ce5SGreg Kroah-Hartman * configured. 121996fd7ce5SGreg Kroah-Hartman * 122096fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 122196fd7ce5SGreg Kroah-Hartman */ 122296fd7ce5SGreg Kroah-Hartman static int tty_driver_install_tty(struct tty_driver *driver, 122396fd7ce5SGreg Kroah-Hartman struct tty_struct *tty) 122496fd7ce5SGreg Kroah-Hartman { 122566d450e8SJiri Slaby return driver->ops->install ? driver->ops->install(driver, tty) : 122666d450e8SJiri Slaby tty_standard_install(driver, tty); 122796fd7ce5SGreg Kroah-Hartman } 122896fd7ce5SGreg Kroah-Hartman 122996fd7ce5SGreg Kroah-Hartman /** 123096fd7ce5SGreg Kroah-Hartman * tty_driver_remove_tty() - remove a tty from the driver tables 123196fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 123296fd7ce5SGreg Kroah-Hartman * @idx: the minor number 123396fd7ce5SGreg Kroah-Hartman * 123496fd7ce5SGreg Kroah-Hartman * Remvoe a tty object from the driver tables. The tty->index field 123596fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. 123696fd7ce5SGreg Kroah-Hartman * 123796fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 123896fd7ce5SGreg Kroah-Hartman */ 123905de87edSPeter Hurley static void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty) 124096fd7ce5SGreg Kroah-Hartman { 124196fd7ce5SGreg Kroah-Hartman if (driver->ops->remove) 124296fd7ce5SGreg Kroah-Hartman driver->ops->remove(driver, tty); 124396fd7ce5SGreg Kroah-Hartman else 124496fd7ce5SGreg Kroah-Hartman driver->ttys[tty->index] = NULL; 124596fd7ce5SGreg Kroah-Hartman } 124696fd7ce5SGreg Kroah-Hartman 124796fd7ce5SGreg Kroah-Hartman /* 124896fd7ce5SGreg Kroah-Hartman * tty_reopen() - fast re-open of an open tty 124996fd7ce5SGreg Kroah-Hartman * @tty - the tty to open 125096fd7ce5SGreg Kroah-Hartman * 125196fd7ce5SGreg Kroah-Hartman * Return 0 on success, -errno on error. 12525d93e748SPeter Hurley * Re-opens on master ptys are not allowed and return -EIO. 125396fd7ce5SGreg Kroah-Hartman * 12545d93e748SPeter Hurley * Locking: Caller must hold tty_lock 125596fd7ce5SGreg Kroah-Hartman */ 125696fd7ce5SGreg Kroah-Hartman static int tty_reopen(struct tty_struct *tty) 125796fd7ce5SGreg Kroah-Hartman { 125896fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 1259fe324167SDmitry Safonov int retval; 126096fd7ce5SGreg Kroah-Hartman 126196fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY && 12625d93e748SPeter Hurley driver->subtype == PTY_TYPE_MASTER) 126396fd7ce5SGreg Kroah-Hartman return -EIO; 126496fd7ce5SGreg Kroah-Hartman 12657f22f6c9SPeter Hurley if (!tty->count) 12667f22f6c9SPeter Hurley return -EAGAIN; 12677f22f6c9SPeter Hurley 126886f2c00fSPeter Hurley if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN)) 126986f2c00fSPeter Hurley return -EBUSY; 127086f2c00fSPeter Hurley 127196fd7ce5SGreg Kroah-Hartman tty->count++; 127296fd7ce5SGreg Kroah-Hartman 1273fe324167SDmitry Safonov if (tty->ldisc) 127496fd7ce5SGreg Kroah-Hartman return 0; 1275fe324167SDmitry Safonov 1276fe324167SDmitry Safonov retval = tty_ldisc_reinit(tty, tty->termios.c_line); 1277fe324167SDmitry Safonov if (retval) 1278fe324167SDmitry Safonov tty->count--; 1279fe324167SDmitry Safonov 1280fe324167SDmitry Safonov return retval; 128196fd7ce5SGreg Kroah-Hartman } 128296fd7ce5SGreg Kroah-Hartman 128396fd7ce5SGreg Kroah-Hartman /** 128496fd7ce5SGreg Kroah-Hartman * tty_init_dev - initialise a tty device 128596fd7ce5SGreg Kroah-Hartman * @driver: tty driver we are opening a device on 128696fd7ce5SGreg Kroah-Hartman * @idx: device index 128796fd7ce5SGreg Kroah-Hartman * @ret_tty: returned tty structure 128896fd7ce5SGreg Kroah-Hartman * 128996fd7ce5SGreg Kroah-Hartman * Prepare a tty device. This may not be a "new" clean device but 129096fd7ce5SGreg Kroah-Hartman * could also be an active device. The pty drivers require special 129196fd7ce5SGreg Kroah-Hartman * handling because of this. 129296fd7ce5SGreg Kroah-Hartman * 129396fd7ce5SGreg Kroah-Hartman * Locking: 129496fd7ce5SGreg Kroah-Hartman * The function is called under the tty_mutex, which 129596fd7ce5SGreg Kroah-Hartman * protects us from the tty struct or driver itself going away. 129696fd7ce5SGreg Kroah-Hartman * 129796fd7ce5SGreg Kroah-Hartman * On exit the tty device has the line discipline attached and 129896fd7ce5SGreg Kroah-Hartman * a reference count of 1. If a pair was created for pty/tty use 129996fd7ce5SGreg Kroah-Hartman * and the other was a pty master then it too has a reference count of 1. 130096fd7ce5SGreg Kroah-Hartman * 130196fd7ce5SGreg Kroah-Hartman * WSH 06/09/97: Rewritten to remove races and properly clean up after a 130296fd7ce5SGreg Kroah-Hartman * failed open. The new code protects the open with a mutex, so it's 130396fd7ce5SGreg Kroah-Hartman * really quite straightforward. The mutex locking can probably be 130496fd7ce5SGreg Kroah-Hartman * relaxed for the (most common) case of reopening a tty. 130596fd7ce5SGreg Kroah-Hartman */ 130696fd7ce5SGreg Kroah-Hartman 1307593a27c4SKonstantin Khlebnikov struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) 130896fd7ce5SGreg Kroah-Hartman { 130996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 131096fd7ce5SGreg Kroah-Hartman int retval; 131196fd7ce5SGreg Kroah-Hartman 131296fd7ce5SGreg Kroah-Hartman /* 131396fd7ce5SGreg Kroah-Hartman * First time open is complex, especially for PTY devices. 131496fd7ce5SGreg Kroah-Hartman * This code guarantees that either everything succeeds and the 131596fd7ce5SGreg Kroah-Hartman * TTY is ready for operation, or else the table slots are vacated 131696fd7ce5SGreg Kroah-Hartman * and the allocated memory released. (Except that the termios 131716b00ae8SJohan Hovold * may be retained.) 131896fd7ce5SGreg Kroah-Hartman */ 131996fd7ce5SGreg Kroah-Hartman 132096fd7ce5SGreg Kroah-Hartman if (!try_module_get(driver->owner)) 132196fd7ce5SGreg Kroah-Hartman return ERR_PTR(-ENODEV); 132296fd7ce5SGreg Kroah-Hartman 13232c964a2fSRasmus Villemoes tty = alloc_tty_struct(driver, idx); 1324d5543503SJiri Slaby if (!tty) { 1325d5543503SJiri Slaby retval = -ENOMEM; 1326d5543503SJiri Slaby goto err_module_put; 1327d5543503SJiri Slaby } 132896fd7ce5SGreg Kroah-Hartman 132989c8d91eSAlan Cox tty_lock(tty); 133096fd7ce5SGreg Kroah-Hartman retval = tty_driver_install_tty(driver, tty); 1331d5543503SJiri Slaby if (retval < 0) 1332c8b710b3SPeter Hurley goto err_free_tty; 133396fd7ce5SGreg Kroah-Hartman 133404831dc1SJiri Slaby if (!tty->port) 133504831dc1SJiri Slaby tty->port = driver->ports[idx]; 133604831dc1SJiri Slaby 13375d4121c0SJiri Slaby WARN_RATELIMIT(!tty->port, 13385d4121c0SJiri Slaby "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", 13395d4121c0SJiri Slaby __func__, tty->driver->name); 13405d4121c0SJiri Slaby 1341b027e229SGaurav Kohli retval = tty_ldisc_lock(tty, 5 * HZ); 1342b027e229SGaurav Kohli if (retval) 1343b027e229SGaurav Kohli goto err_release_lock; 1344967fab69SJiri Slaby tty->port->itty = tty; 1345967fab69SJiri Slaby 134696fd7ce5SGreg Kroah-Hartman /* 134796fd7ce5SGreg Kroah-Hartman * Structures all installed ... call the ldisc open routines. 134896fd7ce5SGreg Kroah-Hartman * If we fail here just call release_tty to clean up. No need 134996fd7ce5SGreg Kroah-Hartman * to decrement the use counts, as release_tty doesn't care. 135096fd7ce5SGreg Kroah-Hartman */ 135196fd7ce5SGreg Kroah-Hartman retval = tty_ldisc_setup(tty, tty->link); 135296fd7ce5SGreg Kroah-Hartman if (retval) 1353d5543503SJiri Slaby goto err_release_tty; 1354b027e229SGaurav Kohli tty_ldisc_unlock(tty); 135589c8d91eSAlan Cox /* Return the tty locked so that it cannot vanish under the caller */ 135696fd7ce5SGreg Kroah-Hartman return tty; 135796fd7ce5SGreg Kroah-Hartman 1358c8b710b3SPeter Hurley err_free_tty: 135989c8d91eSAlan Cox tty_unlock(tty); 1360d5543503SJiri Slaby free_tty_struct(tty); 1361d5543503SJiri Slaby err_module_put: 136296fd7ce5SGreg Kroah-Hartman module_put(driver->owner); 1363d5543503SJiri Slaby return ERR_PTR(retval); 136496fd7ce5SGreg Kroah-Hartman 136596fd7ce5SGreg Kroah-Hartman /* call the tty release_tty routine to clean out this slot */ 1366d5543503SJiri Slaby err_release_tty: 1367b027e229SGaurav Kohli tty_ldisc_unlock(tty); 1368339f36baSPeter Hurley tty_info_ratelimited(tty, "ldisc open failed (%d), clearing slot %d\n", 1369339f36baSPeter Hurley retval, idx); 1370b027e229SGaurav Kohli err_release_lock: 1371b027e229SGaurav Kohli tty_unlock(tty); 137296fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 137396fd7ce5SGreg Kroah-Hartman return ERR_PTR(retval); 137496fd7ce5SGreg Kroah-Hartman } 137596fd7ce5SGreg Kroah-Hartman 1376f51ccf46SJohan Hovold /** 1377f51ccf46SJohan Hovold * tty_save_termios() - save tty termios data in driver table 1378f51ccf46SJohan Hovold * @tty: tty whose termios data to save 1379f51ccf46SJohan Hovold * 1380f51ccf46SJohan Hovold * Locking: Caller guarantees serialisation with tty_init_termios(). 1381f51ccf46SJohan Hovold */ 1382f51ccf46SJohan Hovold void tty_save_termios(struct tty_struct *tty) 138396fd7ce5SGreg Kroah-Hartman { 138496fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 138596fd7ce5SGreg Kroah-Hartman int idx = tty->index; 138636b3c070SAlan Cox 138736b3c070SAlan Cox /* If the port is going to reset then it has no termios to save */ 138836b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 138936b3c070SAlan Cox return; 139036b3c070SAlan Cox 139136b3c070SAlan Cox /* Stash the termios data */ 1392adc8d746SAlan Cox tp = tty->driver->termios[idx]; 139336b3c070SAlan Cox if (tp == NULL) { 139436b3c070SAlan Cox tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL); 139525080652SPeter Hurley if (tp == NULL) 139636b3c070SAlan Cox return; 13974ac5d705SDan Carpenter tty->driver->termios[idx] = tp; 139836b3c070SAlan Cox } 139936b3c070SAlan Cox *tp = tty->termios; 140096fd7ce5SGreg Kroah-Hartman } 1401f51ccf46SJohan Hovold EXPORT_SYMBOL_GPL(tty_save_termios); 140296fd7ce5SGreg Kroah-Hartman 1403a2965b7bSPeter Hurley /** 1404949aa64fSPeter Hurley * tty_flush_works - flush all works of a tty/pty pair 1405949aa64fSPeter Hurley * @tty: tty device to flush works for (or either end of a pty pair) 1406a2965b7bSPeter Hurley * 1407949aa64fSPeter Hurley * Sync flush all works belonging to @tty (and the 'other' tty). 1408a2965b7bSPeter Hurley */ 1409a2965b7bSPeter Hurley static void tty_flush_works(struct tty_struct *tty) 1410a2965b7bSPeter Hurley { 1411a2965b7bSPeter Hurley flush_work(&tty->SAK_work); 1412a2965b7bSPeter Hurley flush_work(&tty->hangup_work); 1413949aa64fSPeter Hurley if (tty->link) { 1414949aa64fSPeter Hurley flush_work(&tty->link->SAK_work); 1415949aa64fSPeter Hurley flush_work(&tty->link->hangup_work); 1416949aa64fSPeter Hurley } 1417a2965b7bSPeter Hurley } 141896fd7ce5SGreg Kroah-Hartman 141996fd7ce5SGreg Kroah-Hartman /** 142096fd7ce5SGreg Kroah-Hartman * release_one_tty - release tty structure memory 142196fd7ce5SGreg Kroah-Hartman * @kref: kref of tty we are obliterating 142296fd7ce5SGreg Kroah-Hartman * 142396fd7ce5SGreg Kroah-Hartman * Releases memory associated with a tty structure, and clears out the 142496fd7ce5SGreg Kroah-Hartman * driver table slots. This function is called when a device is no longer 142596fd7ce5SGreg Kroah-Hartman * in use. It also gets called when setup of a device fails. 142696fd7ce5SGreg Kroah-Hartman * 142796fd7ce5SGreg Kroah-Hartman * Locking: 142896fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 142996fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 143096fd7ce5SGreg Kroah-Hartman * 143196fd7ce5SGreg Kroah-Hartman * This method gets called from a work queue so that the driver private 143296fd7ce5SGreg Kroah-Hartman * cleanup ops can sleep (needed for USB at least) 143396fd7ce5SGreg Kroah-Hartman */ 143496fd7ce5SGreg Kroah-Hartman static void release_one_tty(struct work_struct *work) 143596fd7ce5SGreg Kroah-Hartman { 143696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 143796fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 143896fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 1439b216df53SCyrill Gorcunov struct module *owner = driver->owner; 144096fd7ce5SGreg Kroah-Hartman 144196fd7ce5SGreg Kroah-Hartman if (tty->ops->cleanup) 144296fd7ce5SGreg Kroah-Hartman tty->ops->cleanup(tty); 144396fd7ce5SGreg Kroah-Hartman 144496fd7ce5SGreg Kroah-Hartman tty->magic = 0; 144596fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(driver); 1446b216df53SCyrill Gorcunov module_put(owner); 144796fd7ce5SGreg Kroah-Hartman 14484a510969SPeter Hurley spin_lock(&tty->files_lock); 144996fd7ce5SGreg Kroah-Hartman list_del_init(&tty->tty_files); 14504a510969SPeter Hurley spin_unlock(&tty->files_lock); 145196fd7ce5SGreg Kroah-Hartman 145296fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 145396fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 145496fd7ce5SGreg Kroah-Hartman free_tty_struct(tty); 145596fd7ce5SGreg Kroah-Hartman } 145696fd7ce5SGreg Kroah-Hartman 145796fd7ce5SGreg Kroah-Hartman static void queue_release_one_tty(struct kref *kref) 145896fd7ce5SGreg Kroah-Hartman { 145996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = container_of(kref, struct tty_struct, kref); 146096fd7ce5SGreg Kroah-Hartman 146196fd7ce5SGreg Kroah-Hartman /* The hangup queue is now free so we can reuse it rather than 146296fd7ce5SGreg Kroah-Hartman waste a chunk of memory for each port */ 146396fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, release_one_tty); 146496fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 146596fd7ce5SGreg Kroah-Hartman } 146696fd7ce5SGreg Kroah-Hartman 146796fd7ce5SGreg Kroah-Hartman /** 146896fd7ce5SGreg Kroah-Hartman * tty_kref_put - release a tty kref 146996fd7ce5SGreg Kroah-Hartman * @tty: tty device 147096fd7ce5SGreg Kroah-Hartman * 147196fd7ce5SGreg Kroah-Hartman * Release a reference to a tty device and if need be let the kref 147296fd7ce5SGreg Kroah-Hartman * layer destruct the object for us 147396fd7ce5SGreg Kroah-Hartman */ 147496fd7ce5SGreg Kroah-Hartman 147596fd7ce5SGreg Kroah-Hartman void tty_kref_put(struct tty_struct *tty) 147696fd7ce5SGreg Kroah-Hartman { 147796fd7ce5SGreg Kroah-Hartman if (tty) 147896fd7ce5SGreg Kroah-Hartman kref_put(&tty->kref, queue_release_one_tty); 147996fd7ce5SGreg Kroah-Hartman } 148096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_kref_put); 148196fd7ce5SGreg Kroah-Hartman 148296fd7ce5SGreg Kroah-Hartman /** 148396fd7ce5SGreg Kroah-Hartman * release_tty - release tty structure memory 148496fd7ce5SGreg Kroah-Hartman * 148596fd7ce5SGreg Kroah-Hartman * Release both @tty and a possible linked partner (think pty pair), 148696fd7ce5SGreg Kroah-Hartman * and decrement the refcount of the backing module. 148796fd7ce5SGreg Kroah-Hartman * 148896fd7ce5SGreg Kroah-Hartman * Locking: 1489d155255aSAlan Cox * tty_mutex 149096fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 149196fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 149296fd7ce5SGreg Kroah-Hartman * 149396fd7ce5SGreg Kroah-Hartman */ 149496fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx) 149596fd7ce5SGreg Kroah-Hartman { 149696fd7ce5SGreg Kroah-Hartman /* This should always be true but check for the moment */ 149796fd7ce5SGreg Kroah-Hartman WARN_ON(tty->index != idx); 1498d155255aSAlan Cox WARN_ON(!mutex_is_locked(&tty_mutex)); 149936b3c070SAlan Cox if (tty->ops->shutdown) 150036b3c070SAlan Cox tty->ops->shutdown(tty); 1501f51ccf46SJohan Hovold tty_save_termios(tty); 150236b3c070SAlan Cox tty_driver_remove_tty(tty->driver, tty); 1503967fab69SJiri Slaby tty->port->itty = NULL; 150464e377dcSPeter Hurley if (tty->link) 150564e377dcSPeter Hurley tty->link->port->itty = NULL; 1506e176058fSPeter Hurley tty_buffer_cancel_work(tty->port); 15072b022ab7SSahara if (tty->link) 15082b022ab7SSahara tty_buffer_cancel_work(tty->link->port); 150936b3c070SAlan Cox 151096fd7ce5SGreg Kroah-Hartman tty_kref_put(tty->link); 151196fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 151296fd7ce5SGreg Kroah-Hartman } 151396fd7ce5SGreg Kroah-Hartman 151496fd7ce5SGreg Kroah-Hartman /** 1515955787caSJiri Slaby * tty_release_checks - check a tty before real release 1516955787caSJiri Slaby * @tty: tty to check 1517955787caSJiri Slaby * @o_tty: link of @tty (if any) 1518955787caSJiri Slaby * @idx: index of the tty 1519955787caSJiri Slaby * 1520955787caSJiri Slaby * Performs some paranoid checking before true release of the @tty. 1521955787caSJiri Slaby * This is a no-op unless TTY_PARANOIA_CHECK is defined. 1522955787caSJiri Slaby */ 1523359b9fb5SPeter Hurley static int tty_release_checks(struct tty_struct *tty, int idx) 1524955787caSJiri Slaby { 1525955787caSJiri Slaby #ifdef TTY_PARANOIA_CHECK 1526955787caSJiri Slaby if (idx < 0 || idx >= tty->driver->num) { 1527e2dfa3d3SPeter Hurley tty_debug(tty, "bad idx %d\n", idx); 1528955787caSJiri Slaby return -1; 1529955787caSJiri Slaby } 1530955787caSJiri Slaby 1531955787caSJiri Slaby /* not much to check for devpts */ 1532955787caSJiri Slaby if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) 1533955787caSJiri Slaby return 0; 1534955787caSJiri Slaby 1535955787caSJiri Slaby if (tty != tty->driver->ttys[idx]) { 1536e2dfa3d3SPeter Hurley tty_debug(tty, "bad driver table[%d] = %p\n", 1537e2dfa3d3SPeter Hurley idx, tty->driver->ttys[idx]); 1538955787caSJiri Slaby return -1; 1539955787caSJiri Slaby } 1540955787caSJiri Slaby if (tty->driver->other) { 1541359b9fb5SPeter Hurley struct tty_struct *o_tty = tty->link; 1542359b9fb5SPeter Hurley 1543955787caSJiri Slaby if (o_tty != tty->driver->other->ttys[idx]) { 1544e2dfa3d3SPeter Hurley tty_debug(tty, "bad other table[%d] = %p\n", 1545e2dfa3d3SPeter Hurley idx, tty->driver->other->ttys[idx]); 1546955787caSJiri Slaby return -1; 1547955787caSJiri Slaby } 1548955787caSJiri Slaby if (o_tty->link != tty) { 1549e2dfa3d3SPeter Hurley tty_debug(tty, "bad link = %p\n", o_tty->link); 1550955787caSJiri Slaby return -1; 1551955787caSJiri Slaby } 1552955787caSJiri Slaby } 1553955787caSJiri Slaby #endif 1554955787caSJiri Slaby return 0; 1555955787caSJiri Slaby } 1556955787caSJiri Slaby 1557955787caSJiri Slaby /** 1558a09ac397SOkash Khawaja * tty_kclose - closes tty opened by tty_kopen 1559a09ac397SOkash Khawaja * @tty: tty device 1560a09ac397SOkash Khawaja * 1561a09ac397SOkash Khawaja * Performs the final steps to release and free a tty device. It is the 1562a09ac397SOkash Khawaja * same as tty_release_struct except that it also resets TTY_PORT_KOPENED 1563a09ac397SOkash Khawaja * flag on tty->port. 1564a09ac397SOkash Khawaja */ 1565a09ac397SOkash Khawaja void tty_kclose(struct tty_struct *tty) 1566a09ac397SOkash Khawaja { 1567a09ac397SOkash Khawaja /* 1568a09ac397SOkash Khawaja * Ask the line discipline code to release its structures 1569a09ac397SOkash Khawaja */ 1570a09ac397SOkash Khawaja tty_ldisc_release(tty); 1571a09ac397SOkash Khawaja 1572a09ac397SOkash Khawaja /* Wait for pending work before tty destruction commmences */ 1573a09ac397SOkash Khawaja tty_flush_works(tty); 1574a09ac397SOkash Khawaja 1575a09ac397SOkash Khawaja tty_debug_hangup(tty, "freeing structure\n"); 1576a09ac397SOkash Khawaja /* 1577a09ac397SOkash Khawaja * The release_tty function takes care of the details of clearing 1578a09ac397SOkash Khawaja * the slots and preserving the termios structure. The tty_unlock_pair 1579a09ac397SOkash Khawaja * should be safe as we keep a kref while the tty is locked (so the 1580a09ac397SOkash Khawaja * unlock never unlocks a freed tty). 1581a09ac397SOkash Khawaja */ 1582a09ac397SOkash Khawaja mutex_lock(&tty_mutex); 1583a09ac397SOkash Khawaja tty_port_set_kopened(tty->port, 0); 1584a09ac397SOkash Khawaja release_tty(tty, tty->index); 1585a09ac397SOkash Khawaja mutex_unlock(&tty_mutex); 1586a09ac397SOkash Khawaja } 1587a09ac397SOkash Khawaja EXPORT_SYMBOL_GPL(tty_kclose); 1588a09ac397SOkash Khawaja 1589a09ac397SOkash Khawaja /** 15909ed90d20SRob Herring * tty_release_struct - release a tty struct 15919ed90d20SRob Herring * @tty: tty device 15929ed90d20SRob Herring * @idx: index of the tty 15939ed90d20SRob Herring * 15949ed90d20SRob Herring * Performs the final steps to release and free a tty device. It is 15959ed90d20SRob Herring * roughly the reverse of tty_init_dev. 15969ed90d20SRob Herring */ 15979ed90d20SRob Herring void tty_release_struct(struct tty_struct *tty, int idx) 15989ed90d20SRob Herring { 15999ed90d20SRob Herring /* 16009ed90d20SRob Herring * Ask the line discipline code to release its structures 16019ed90d20SRob Herring */ 16029ed90d20SRob Herring tty_ldisc_release(tty); 16039ed90d20SRob Herring 16049ed90d20SRob Herring /* Wait for pending work before tty destruction commmences */ 16059ed90d20SRob Herring tty_flush_works(tty); 16069ed90d20SRob Herring 16079ed90d20SRob Herring tty_debug_hangup(tty, "freeing structure\n"); 16089ed90d20SRob Herring /* 16099ed90d20SRob Herring * The release_tty function takes care of the details of clearing 16109ed90d20SRob Herring * the slots and preserving the termios structure. The tty_unlock_pair 16119ed90d20SRob Herring * should be safe as we keep a kref while the tty is locked (so the 16129ed90d20SRob Herring * unlock never unlocks a freed tty). 16139ed90d20SRob Herring */ 16149ed90d20SRob Herring mutex_lock(&tty_mutex); 16159ed90d20SRob Herring release_tty(tty, idx); 16169ed90d20SRob Herring mutex_unlock(&tty_mutex); 16179ed90d20SRob Herring } 16189ed90d20SRob Herring EXPORT_SYMBOL_GPL(tty_release_struct); 16199ed90d20SRob Herring 16209ed90d20SRob Herring /** 162196fd7ce5SGreg Kroah-Hartman * tty_release - vfs callback for close 162296fd7ce5SGreg Kroah-Hartman * @inode: inode of tty 162396fd7ce5SGreg Kroah-Hartman * @filp: file pointer for handle to tty 162496fd7ce5SGreg Kroah-Hartman * 162596fd7ce5SGreg Kroah-Hartman * Called the last time each file handle is closed that references 162696fd7ce5SGreg Kroah-Hartman * this tty. There may however be several such references. 162796fd7ce5SGreg Kroah-Hartman * 162896fd7ce5SGreg Kroah-Hartman * Locking: 162996fd7ce5SGreg Kroah-Hartman * Takes bkl. See tty_release_dev 163096fd7ce5SGreg Kroah-Hartman * 163196fd7ce5SGreg Kroah-Hartman * Even releasing the tty structures is a tricky business.. We have 163296fd7ce5SGreg Kroah-Hartman * to be very careful that the structures are all released at the 163396fd7ce5SGreg Kroah-Hartman * same time, as interrupts might otherwise get the wrong pointers. 163496fd7ce5SGreg Kroah-Hartman * 163596fd7ce5SGreg Kroah-Hartman * WSH 09/09/97: rewritten to avoid some nasty race conditions that could 163696fd7ce5SGreg Kroah-Hartman * lead to double frees or releasing memory still in use. 163796fd7ce5SGreg Kroah-Hartman */ 163896fd7ce5SGreg Kroah-Hartman 163996fd7ce5SGreg Kroah-Hartman int tty_release(struct inode *inode, struct file *filp) 164096fd7ce5SGreg Kroah-Hartman { 164196fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 16427ffb6da9SPeter Hurley struct tty_struct *o_tty = NULL; 16437ffb6da9SPeter Hurley int do_sleep, final; 164496fd7ce5SGreg Kroah-Hartman int idx; 164537b16457SPeter Hurley long timeout = 0; 1646494c1eacSPeter Hurley int once = 1; 164796fd7ce5SGreg Kroah-Hartman 16489de44bd6SJiri Slaby if (tty_paranoia_check(tty, inode, __func__)) 164996fd7ce5SGreg Kroah-Hartman return 0; 165096fd7ce5SGreg Kroah-Hartman 165189c8d91eSAlan Cox tty_lock(tty); 16529de44bd6SJiri Slaby check_tty_count(tty, __func__); 165396fd7ce5SGreg Kroah-Hartman 165496fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); 165596fd7ce5SGreg Kroah-Hartman 165696fd7ce5SGreg Kroah-Hartman idx = tty->index; 16577ffb6da9SPeter Hurley if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 16587ffb6da9SPeter Hurley tty->driver->subtype == PTY_TYPE_MASTER) 165996fd7ce5SGreg Kroah-Hartman o_tty = tty->link; 166096fd7ce5SGreg Kroah-Hartman 1661359b9fb5SPeter Hurley if (tty_release_checks(tty, idx)) { 166289c8d91eSAlan Cox tty_unlock(tty); 166396fd7ce5SGreg Kroah-Hartman return 0; 166496fd7ce5SGreg Kroah-Hartman } 166596fd7ce5SGreg Kroah-Hartman 1666d435cefeSPeter Hurley tty_debug_hangup(tty, "releasing (count=%d)\n", tty->count); 166796fd7ce5SGreg Kroah-Hartman 166896fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 166996fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, filp); 167096fd7ce5SGreg Kroah-Hartman 16712aff5e2bSPeter Hurley /* If tty is pty master, lock the slave pty (stable lock order) */ 16722aff5e2bSPeter Hurley tty_lock_slave(o_tty); 16732aff5e2bSPeter Hurley 167496fd7ce5SGreg Kroah-Hartman /* 167596fd7ce5SGreg Kroah-Hartman * Sanity check: if tty->count is going to zero, there shouldn't be 167696fd7ce5SGreg Kroah-Hartman * any waiters on tty->read_wait or tty->write_wait. We test the 167796fd7ce5SGreg Kroah-Hartman * wait queues and kick everyone out _before_ actually starting to 167896fd7ce5SGreg Kroah-Hartman * close. This ensures that we won't block while releasing the tty 167996fd7ce5SGreg Kroah-Hartman * structure. 168096fd7ce5SGreg Kroah-Hartman * 168196fd7ce5SGreg Kroah-Hartman * The test for the o_tty closing is necessary, since the master and 168296fd7ce5SGreg Kroah-Hartman * slave sides may close in any order. If the slave side closes out 168396fd7ce5SGreg Kroah-Hartman * first, its count will be one, since the master side holds an open. 1684324c1650SPeter Hurley * Thus this test wouldn't be triggered at the time the slave closed, 168596fd7ce5SGreg Kroah-Hartman * so we do it now. 168696fd7ce5SGreg Kroah-Hartman */ 1687d5e370a4SPeter Hurley while (1) { 168896fd7ce5SGreg Kroah-Hartman do_sleep = 0; 168996fd7ce5SGreg Kroah-Hartman 1690324c1650SPeter Hurley if (tty->count <= 1) { 169196fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->read_wait)) { 1692a9a08845SLinus Torvalds wake_up_poll(&tty->read_wait, EPOLLIN); 169396fd7ce5SGreg Kroah-Hartman do_sleep++; 169496fd7ce5SGreg Kroah-Hartman } 169596fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->write_wait)) { 1696a9a08845SLinus Torvalds wake_up_poll(&tty->write_wait, EPOLLOUT); 169796fd7ce5SGreg Kroah-Hartman do_sleep++; 169896fd7ce5SGreg Kroah-Hartman } 169996fd7ce5SGreg Kroah-Hartman } 17007ffb6da9SPeter Hurley if (o_tty && o_tty->count <= 1) { 170196fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->read_wait)) { 1702a9a08845SLinus Torvalds wake_up_poll(&o_tty->read_wait, EPOLLIN); 170396fd7ce5SGreg Kroah-Hartman do_sleep++; 170496fd7ce5SGreg Kroah-Hartman } 170596fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->write_wait)) { 1706a9a08845SLinus Torvalds wake_up_poll(&o_tty->write_wait, EPOLLOUT); 170796fd7ce5SGreg Kroah-Hartman do_sleep++; 170896fd7ce5SGreg Kroah-Hartman } 170996fd7ce5SGreg Kroah-Hartman } 171096fd7ce5SGreg Kroah-Hartman if (!do_sleep) 171196fd7ce5SGreg Kroah-Hartman break; 171296fd7ce5SGreg Kroah-Hartman 1713494c1eacSPeter Hurley if (once) { 1714494c1eacSPeter Hurley once = 0; 1715339f36baSPeter Hurley tty_warn(tty, "read/write wait queue active!\n"); 1716494c1eacSPeter Hurley } 171737b16457SPeter Hurley schedule_timeout_killable(timeout); 171837b16457SPeter Hurley if (timeout < 120 * HZ) 171937b16457SPeter Hurley timeout = 2 * timeout + 1; 172037b16457SPeter Hurley else 172137b16457SPeter Hurley timeout = MAX_SCHEDULE_TIMEOUT; 172296fd7ce5SGreg Kroah-Hartman } 172396fd7ce5SGreg Kroah-Hartman 17247ffb6da9SPeter Hurley if (o_tty) { 172596fd7ce5SGreg Kroah-Hartman if (--o_tty->count < 0) { 1726339f36baSPeter Hurley tty_warn(tty, "bad slave count (%d)\n", o_tty->count); 172796fd7ce5SGreg Kroah-Hartman o_tty->count = 0; 172896fd7ce5SGreg Kroah-Hartman } 172996fd7ce5SGreg Kroah-Hartman } 173096fd7ce5SGreg Kroah-Hartman if (--tty->count < 0) { 1731339f36baSPeter Hurley tty_warn(tty, "bad tty->count (%d)\n", tty->count); 173296fd7ce5SGreg Kroah-Hartman tty->count = 0; 173396fd7ce5SGreg Kroah-Hartman } 173496fd7ce5SGreg Kroah-Hartman 173596fd7ce5SGreg Kroah-Hartman /* 173696fd7ce5SGreg Kroah-Hartman * We've decremented tty->count, so we need to remove this file 173796fd7ce5SGreg Kroah-Hartman * descriptor off the tty->tty_files list; this serves two 173896fd7ce5SGreg Kroah-Hartman * purposes: 173996fd7ce5SGreg Kroah-Hartman * - check_tty_count sees the correct number of file descriptors 174096fd7ce5SGreg Kroah-Hartman * associated with this tty. 174196fd7ce5SGreg Kroah-Hartman * - do_tty_hangup no longer sees this file descriptor as 174296fd7ce5SGreg Kroah-Hartman * something that needs to be handled for hangups. 174396fd7ce5SGreg Kroah-Hartman */ 174496fd7ce5SGreg Kroah-Hartman tty_del_file(filp); 174596fd7ce5SGreg Kroah-Hartman 174696fd7ce5SGreg Kroah-Hartman /* 174796fd7ce5SGreg Kroah-Hartman * Perform some housekeeping before deciding whether to return. 174896fd7ce5SGreg Kroah-Hartman * 174996fd7ce5SGreg Kroah-Hartman * If _either_ side is closing, make sure there aren't any 175096fd7ce5SGreg Kroah-Hartman * processes that still think tty or o_tty is their controlling 175196fd7ce5SGreg Kroah-Hartman * tty. 175296fd7ce5SGreg Kroah-Hartman */ 1753324c1650SPeter Hurley if (!tty->count) { 175496fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 175596fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 17567ffb6da9SPeter Hurley if (o_tty) 175796fd7ce5SGreg Kroah-Hartman session_clear_tty(o_tty->session); 175896fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 175996fd7ce5SGreg Kroah-Hartman } 176096fd7ce5SGreg Kroah-Hartman 1761324c1650SPeter Hurley /* check whether both sides are closing ... */ 17627ffb6da9SPeter Hurley final = !tty->count && !(o_tty && o_tty->count); 1763324c1650SPeter Hurley 17642aff5e2bSPeter Hurley tty_unlock_slave(o_tty); 17652aff5e2bSPeter Hurley tty_unlock(tty); 17662aff5e2bSPeter Hurley 176704980706SPeter Hurley /* At this point, the tty->count == 0 should ensure a dead tty 1768d155255aSAlan Cox cannot be re-opened by a racing opener */ 176996fd7ce5SGreg Kroah-Hartman 1770324c1650SPeter Hurley if (!final) 177196fd7ce5SGreg Kroah-Hartman return 0; 177296fd7ce5SGreg Kroah-Hartman 1773accff793SPeter Hurley tty_debug_hangup(tty, "final close\n"); 1774a2965b7bSPeter Hurley 17759ed90d20SRob Herring tty_release_struct(tty, idx); 177696fd7ce5SGreg Kroah-Hartman return 0; 177796fd7ce5SGreg Kroah-Hartman } 177896fd7ce5SGreg Kroah-Hartman 177996fd7ce5SGreg Kroah-Hartman /** 178052494eebSPeter Hurley * tty_open_current_tty - get locked tty of current task 1781b82154acSJiri Slaby * @device: device number 1782b82154acSJiri Slaby * @filp: file pointer to tty 178352494eebSPeter Hurley * @return: locked tty of the current task iff @device is /dev/tty 178452494eebSPeter Hurley * 178552494eebSPeter Hurley * Performs a re-open of the current task's controlling tty. 1786b82154acSJiri Slaby * 1787b82154acSJiri Slaby * We cannot return driver and index like for the other nodes because 1788b82154acSJiri Slaby * devpts will not work then. It expects inodes to be from devpts FS. 1789b82154acSJiri Slaby */ 1790b82154acSJiri Slaby static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) 1791b82154acSJiri Slaby { 1792b82154acSJiri Slaby struct tty_struct *tty; 179352494eebSPeter Hurley int retval; 1794b82154acSJiri Slaby 1795b82154acSJiri Slaby if (device != MKDEV(TTYAUX_MAJOR, 0)) 1796b82154acSJiri Slaby return NULL; 1797b82154acSJiri Slaby 1798b82154acSJiri Slaby tty = get_current_tty(); 1799b82154acSJiri Slaby if (!tty) 1800b82154acSJiri Slaby return ERR_PTR(-ENXIO); 1801b82154acSJiri Slaby 1802b82154acSJiri Slaby filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ 1803b82154acSJiri Slaby /* noctty = 1; */ 180452494eebSPeter Hurley tty_lock(tty); 180552494eebSPeter Hurley tty_kref_put(tty); /* safe to drop the kref now */ 180652494eebSPeter Hurley 180752494eebSPeter Hurley retval = tty_reopen(tty); 180852494eebSPeter Hurley if (retval < 0) { 180952494eebSPeter Hurley tty_unlock(tty); 181052494eebSPeter Hurley tty = ERR_PTR(retval); 181152494eebSPeter Hurley } 1812b82154acSJiri Slaby return tty; 1813b82154acSJiri Slaby } 1814b82154acSJiri Slaby 1815b82154acSJiri Slaby /** 18165b5e7040SJiri Slaby * tty_lookup_driver - lookup a tty driver for a given device file 18175b5e7040SJiri Slaby * @device: device number 18185b5e7040SJiri Slaby * @filp: file pointer to tty 18195b5e7040SJiri Slaby * @index: index for the device in the @return driver 18205b5e7040SJiri Slaby * @return: driver for this inode (with increased refcount) 18215b5e7040SJiri Slaby * 18225b5e7040SJiri Slaby * If @return is not erroneous, the caller is responsible to decrement the 18235b5e7040SJiri Slaby * refcount by tty_driver_kref_put. 18245b5e7040SJiri Slaby * 18255b5e7040SJiri Slaby * Locking: tty_mutex protects get_tty_driver 18265b5e7040SJiri Slaby */ 18275b5e7040SJiri Slaby static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp, 182811e1d4aaSPeter Hurley int *index) 18295b5e7040SJiri Slaby { 18305b5e7040SJiri Slaby struct tty_driver *driver; 18315b5e7040SJiri Slaby 18322cd0050cSJiri Slaby switch (device) { 18335b5e7040SJiri Slaby #ifdef CONFIG_VT 18342cd0050cSJiri Slaby case MKDEV(TTY_MAJOR, 0): { 18355b5e7040SJiri Slaby extern struct tty_driver *console_driver; 18365b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 18375b5e7040SJiri Slaby *index = fg_console; 18382cd0050cSJiri Slaby break; 18395b5e7040SJiri Slaby } 18405b5e7040SJiri Slaby #endif 18412cd0050cSJiri Slaby case MKDEV(TTYAUX_MAJOR, 1): { 18425b5e7040SJiri Slaby struct tty_driver *console_driver = console_device(index); 18435b5e7040SJiri Slaby if (console_driver) { 18445b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 184512e84c71SOkash Khawaja if (driver && filp) { 18465b5e7040SJiri Slaby /* Don't let /dev/console block */ 18475b5e7040SJiri Slaby filp->f_flags |= O_NONBLOCK; 18482cd0050cSJiri Slaby break; 18495b5e7040SJiri Slaby } 18505b5e7040SJiri Slaby } 18515b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 18525b5e7040SJiri Slaby } 18532cd0050cSJiri Slaby default: 18545b5e7040SJiri Slaby driver = get_tty_driver(device, index); 18555b5e7040SJiri Slaby if (!driver) 18565b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 18572cd0050cSJiri Slaby break; 18582cd0050cSJiri Slaby } 18595b5e7040SJiri Slaby return driver; 18605b5e7040SJiri Slaby } 18615b5e7040SJiri Slaby 18625b5e7040SJiri Slaby /** 1863a09ac397SOkash Khawaja * tty_kopen - open a tty device for kernel 1864a09ac397SOkash Khawaja * @device: dev_t of device to open 1865a09ac397SOkash Khawaja * 1866a09ac397SOkash Khawaja * Opens tty exclusively for kernel. Performs the driver lookup, 1867a09ac397SOkash Khawaja * makes sure it's not already opened and performs the first-time 1868a09ac397SOkash Khawaja * tty initialization. 1869a09ac397SOkash Khawaja * 1870a09ac397SOkash Khawaja * Returns the locked initialized &tty_struct 1871a09ac397SOkash Khawaja * 1872a09ac397SOkash Khawaja * Claims the global tty_mutex to serialize: 1873a09ac397SOkash Khawaja * - concurrent first-time tty initialization 1874a09ac397SOkash Khawaja * - concurrent tty driver removal w/ lookup 1875a09ac397SOkash Khawaja * - concurrent tty removal from driver table 1876a09ac397SOkash Khawaja */ 1877a09ac397SOkash Khawaja struct tty_struct *tty_kopen(dev_t device) 1878a09ac397SOkash Khawaja { 1879a09ac397SOkash Khawaja struct tty_struct *tty; 1880a09ac397SOkash Khawaja struct tty_driver *driver = NULL; 1881a09ac397SOkash Khawaja int index = -1; 1882a09ac397SOkash Khawaja 1883a09ac397SOkash Khawaja mutex_lock(&tty_mutex); 1884a09ac397SOkash Khawaja driver = tty_lookup_driver(device, NULL, &index); 1885a09ac397SOkash Khawaja if (IS_ERR(driver)) { 1886a09ac397SOkash Khawaja mutex_unlock(&tty_mutex); 1887a09ac397SOkash Khawaja return ERR_CAST(driver); 1888a09ac397SOkash Khawaja } 1889a09ac397SOkash Khawaja 1890a09ac397SOkash Khawaja /* check whether we're reopening an existing tty */ 1891a09ac397SOkash Khawaja tty = tty_driver_lookup_tty(driver, NULL, index); 1892a09ac397SOkash Khawaja if (IS_ERR(tty)) 1893a09ac397SOkash Khawaja goto out; 1894a09ac397SOkash Khawaja 1895a09ac397SOkash Khawaja if (tty) { 1896a09ac397SOkash Khawaja /* drop kref from tty_driver_lookup_tty() */ 1897a09ac397SOkash Khawaja tty_kref_put(tty); 1898a09ac397SOkash Khawaja tty = ERR_PTR(-EBUSY); 1899a09ac397SOkash Khawaja } else { /* tty_init_dev returns tty with the tty_lock held */ 1900a09ac397SOkash Khawaja tty = tty_init_dev(driver, index); 1901a09ac397SOkash Khawaja if (IS_ERR(tty)) 1902a09ac397SOkash Khawaja goto out; 1903a09ac397SOkash Khawaja tty_port_set_kopened(tty->port, 1); 1904a09ac397SOkash Khawaja } 1905a09ac397SOkash Khawaja out: 1906a09ac397SOkash Khawaja mutex_unlock(&tty_mutex); 1907a09ac397SOkash Khawaja tty_driver_kref_put(driver); 1908a09ac397SOkash Khawaja return tty; 1909a09ac397SOkash Khawaja } 1910a09ac397SOkash Khawaja EXPORT_SYMBOL_GPL(tty_kopen); 1911a09ac397SOkash Khawaja 1912a09ac397SOkash Khawaja /** 1913d6203d0cSPeter Hurley * tty_open_by_driver - open a tty device 1914d6203d0cSPeter Hurley * @device: dev_t of device to open 1915d6203d0cSPeter Hurley * @inode: inode of device file 1916d6203d0cSPeter Hurley * @filp: file pointer to tty 1917d6203d0cSPeter Hurley * 1918d6203d0cSPeter Hurley * Performs the driver lookup, checks for a reopen, or otherwise 1919d6203d0cSPeter Hurley * performs the first-time tty initialization. 1920d6203d0cSPeter Hurley * 1921d6203d0cSPeter Hurley * Returns the locked initialized or re-opened &tty_struct 1922d6203d0cSPeter Hurley * 1923d6203d0cSPeter Hurley * Claims the global tty_mutex to serialize: 1924d6203d0cSPeter Hurley * - concurrent first-time tty initialization 1925d6203d0cSPeter Hurley * - concurrent tty driver removal w/ lookup 1926d6203d0cSPeter Hurley * - concurrent tty removal from driver table 1927d6203d0cSPeter Hurley */ 1928a033c3b1SOkash Khawaja static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode, 1929d6203d0cSPeter Hurley struct file *filp) 1930d6203d0cSPeter Hurley { 1931d6203d0cSPeter Hurley struct tty_struct *tty; 1932d6203d0cSPeter Hurley struct tty_driver *driver = NULL; 1933d6203d0cSPeter Hurley int index = -1; 1934d6203d0cSPeter Hurley int retval; 1935d6203d0cSPeter Hurley 1936d6203d0cSPeter Hurley mutex_lock(&tty_mutex); 1937d6203d0cSPeter Hurley driver = tty_lookup_driver(device, filp, &index); 1938d6203d0cSPeter Hurley if (IS_ERR(driver)) { 1939d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 1940d6203d0cSPeter Hurley return ERR_CAST(driver); 1941d6203d0cSPeter Hurley } 1942d6203d0cSPeter Hurley 1943d6203d0cSPeter Hurley /* check whether we're reopening an existing tty */ 19448ead9dd5SLinus Torvalds tty = tty_driver_lookup_tty(driver, filp, index); 1945d6203d0cSPeter Hurley if (IS_ERR(tty)) { 1946d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 1947d6203d0cSPeter Hurley goto out; 1948d6203d0cSPeter Hurley } 1949d6203d0cSPeter Hurley 1950d6203d0cSPeter Hurley if (tty) { 1951a09ac397SOkash Khawaja if (tty_port_kopened(tty->port)) { 1952a09ac397SOkash Khawaja tty_kref_put(tty); 1953a09ac397SOkash Khawaja mutex_unlock(&tty_mutex); 1954a09ac397SOkash Khawaja tty = ERR_PTR(-EBUSY); 1955a09ac397SOkash Khawaja goto out; 1956a09ac397SOkash Khawaja } 1957d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 1958d6203d0cSPeter Hurley retval = tty_lock_interruptible(tty); 19595e00bbfbSPeter Hurley tty_kref_put(tty); /* drop kref from tty_driver_lookup_tty() */ 1960d6203d0cSPeter Hurley if (retval) { 1961d6203d0cSPeter Hurley if (retval == -EINTR) 1962d6203d0cSPeter Hurley retval = -ERESTARTSYS; 1963d6203d0cSPeter Hurley tty = ERR_PTR(retval); 1964d6203d0cSPeter Hurley goto out; 1965d6203d0cSPeter Hurley } 1966d6203d0cSPeter Hurley retval = tty_reopen(tty); 1967d6203d0cSPeter Hurley if (retval < 0) { 1968d6203d0cSPeter Hurley tty_unlock(tty); 1969d6203d0cSPeter Hurley tty = ERR_PTR(retval); 1970d6203d0cSPeter Hurley } 1971d6203d0cSPeter Hurley } else { /* Returns with the tty_lock held for now */ 1972d6203d0cSPeter Hurley tty = tty_init_dev(driver, index); 1973d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 1974d6203d0cSPeter Hurley } 1975d6203d0cSPeter Hurley out: 1976d6203d0cSPeter Hurley tty_driver_kref_put(driver); 1977d6203d0cSPeter Hurley return tty; 1978d6203d0cSPeter Hurley } 1979d6203d0cSPeter Hurley 1980d6203d0cSPeter Hurley /** 198196fd7ce5SGreg Kroah-Hartman * tty_open - open a tty device 198296fd7ce5SGreg Kroah-Hartman * @inode: inode of device file 198396fd7ce5SGreg Kroah-Hartman * @filp: file pointer to tty 198496fd7ce5SGreg Kroah-Hartman * 198596fd7ce5SGreg Kroah-Hartman * tty_open and tty_release keep up the tty count that contains the 198696fd7ce5SGreg Kroah-Hartman * number of opens done on a tty. We cannot use the inode-count, as 198796fd7ce5SGreg Kroah-Hartman * different inodes might point to the same tty. 198896fd7ce5SGreg Kroah-Hartman * 198996fd7ce5SGreg Kroah-Hartman * Open-counting is needed for pty masters, as well as for keeping 199096fd7ce5SGreg Kroah-Hartman * track of serial lines: DTR is dropped when the last close happens. 199196fd7ce5SGreg Kroah-Hartman * (This is not done solely through tty->count, now. - Ted 1/27/92) 199296fd7ce5SGreg Kroah-Hartman * 199396fd7ce5SGreg Kroah-Hartman * The termios state of a pty is reset on first open so that 199496fd7ce5SGreg Kroah-Hartman * settings don't persist across reuse. 199596fd7ce5SGreg Kroah-Hartman * 19965b5e7040SJiri Slaby * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev. 199796fd7ce5SGreg Kroah-Hartman * tty->count should protect the rest. 199896fd7ce5SGreg Kroah-Hartman * ->siglock protects ->signal/->sighand 199989c8d91eSAlan Cox * 200089c8d91eSAlan Cox * Note: the tty_unlock/lock cases without a ref are only safe due to 200189c8d91eSAlan Cox * tty_mutex 200296fd7ce5SGreg Kroah-Hartman */ 200396fd7ce5SGreg Kroah-Hartman 200496fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *inode, struct file *filp) 200596fd7ce5SGreg Kroah-Hartman { 2006b82154acSJiri Slaby struct tty_struct *tty; 200796fd7ce5SGreg Kroah-Hartman int noctty, retval; 200896fd7ce5SGreg Kroah-Hartman dev_t device = inode->i_rdev; 200996fd7ce5SGreg Kroah-Hartman unsigned saved_flags = filp->f_flags; 201096fd7ce5SGreg Kroah-Hartman 201196fd7ce5SGreg Kroah-Hartman nonseekable_open(inode, filp); 201296fd7ce5SGreg Kroah-Hartman 201396fd7ce5SGreg Kroah-Hartman retry_open: 2014fa90e1c9SJiri Slaby retval = tty_alloc_file(filp); 2015fa90e1c9SJiri Slaby if (retval) 2016fa90e1c9SJiri Slaby return -ENOMEM; 2017fa90e1c9SJiri Slaby 2018b82154acSJiri Slaby tty = tty_open_current_tty(device, filp); 2019d6203d0cSPeter Hurley if (!tty) 2020d6203d0cSPeter Hurley tty = tty_open_by_driver(device, inode, filp); 202152494eebSPeter Hurley 202296fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty)) { 2023d6203d0cSPeter Hurley tty_free_file(filp); 2024ba5db448SJiri Slaby retval = PTR_ERR(tty); 20257f22f6c9SPeter Hurley if (retval != -EAGAIN || signal_pending(current)) 2026d6203d0cSPeter Hurley return retval; 20277f22f6c9SPeter Hurley schedule(); 20287f22f6c9SPeter Hurley goto retry_open; 202996fd7ce5SGreg Kroah-Hartman } 203096fd7ce5SGreg Kroah-Hartman 2031fa90e1c9SJiri Slaby tty_add_file(tty, filp); 203296fd7ce5SGreg Kroah-Hartman 20339de44bd6SJiri Slaby check_tty_count(tty, __func__); 2034d435cefeSPeter Hurley tty_debug_hangup(tty, "opening (count=%d)\n", tty->count); 2035accff793SPeter Hurley 203696fd7ce5SGreg Kroah-Hartman if (tty->ops->open) 203796fd7ce5SGreg Kroah-Hartman retval = tty->ops->open(tty, filp); 203896fd7ce5SGreg Kroah-Hartman else 203996fd7ce5SGreg Kroah-Hartman retval = -ENODEV; 204096fd7ce5SGreg Kroah-Hartman filp->f_flags = saved_flags; 204196fd7ce5SGreg Kroah-Hartman 204296fd7ce5SGreg Kroah-Hartman if (retval) { 2043d435cefeSPeter Hurley tty_debug_hangup(tty, "open error %d, releasing\n", retval); 2044accff793SPeter Hurley 204589c8d91eSAlan Cox tty_unlock(tty); /* need to call tty_release without BTM */ 204696fd7ce5SGreg Kroah-Hartman tty_release(inode, filp); 204796fd7ce5SGreg Kroah-Hartman if (retval != -ERESTARTSYS) 204896fd7ce5SGreg Kroah-Hartman return retval; 204996fd7ce5SGreg Kroah-Hartman 205096fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 205196fd7ce5SGreg Kroah-Hartman return retval; 205296fd7ce5SGreg Kroah-Hartman 205396fd7ce5SGreg Kroah-Hartman schedule(); 205496fd7ce5SGreg Kroah-Hartman /* 205596fd7ce5SGreg Kroah-Hartman * Need to reset f_op in case a hangup happened. 205696fd7ce5SGreg Kroah-Hartman */ 20571256937fSPeter Hurley if (tty_hung_up_p(filp)) 205896fd7ce5SGreg Kroah-Hartman filp->f_op = &tty_fops; 205996fd7ce5SGreg Kroah-Hartman goto retry_open; 206096fd7ce5SGreg Kroah-Hartman } 2061d4855e1fSPeter Hurley clear_bit(TTY_HUPPED, &tty->flags); 206296fd7ce5SGreg Kroah-Hartman 206311e1d4aaSPeter Hurley noctty = (filp->f_flags & O_NOCTTY) || 2064da5a0fc6SPeter Hurley (IS_ENABLED(CONFIG_VT) && device == MKDEV(TTY_MAJOR, 0)) || 206511e1d4aaSPeter Hurley device == MKDEV(TTYAUX_MAJOR, 1) || 206611e1d4aaSPeter Hurley (tty->driver->type == TTY_DRIVER_TYPE_PTY && 206711e1d4aaSPeter Hurley tty->driver->subtype == PTY_TYPE_MASTER); 2068a1235b3eSNicolas Pitre if (!noctty) 2069a1235b3eSNicolas Pitre tty_open_proc_set_tty(filp, tty); 207089c8d91eSAlan Cox tty_unlock(tty); 207196fd7ce5SGreg Kroah-Hartman return 0; 207296fd7ce5SGreg Kroah-Hartman } 207396fd7ce5SGreg Kroah-Hartman 207496fd7ce5SGreg Kroah-Hartman 207596fd7ce5SGreg Kroah-Hartman 207696fd7ce5SGreg Kroah-Hartman /** 207796fd7ce5SGreg Kroah-Hartman * tty_poll - check tty status 207896fd7ce5SGreg Kroah-Hartman * @filp: file being polled 207996fd7ce5SGreg Kroah-Hartman * @wait: poll wait structures to update 208096fd7ce5SGreg Kroah-Hartman * 208196fd7ce5SGreg Kroah-Hartman * Call the line discipline polling method to obtain the poll 208296fd7ce5SGreg Kroah-Hartman * status of the device. 208396fd7ce5SGreg Kroah-Hartman * 208496fd7ce5SGreg Kroah-Hartman * Locking: locks called line discipline but ldisc poll method 208596fd7ce5SGreg Kroah-Hartman * may be re-entered freely by other callers. 208696fd7ce5SGreg Kroah-Hartman */ 208796fd7ce5SGreg Kroah-Hartman 2088afc9a42bSAl Viro static __poll_t tty_poll(struct file *filp, poll_table *wait) 208996fd7ce5SGreg Kroah-Hartman { 209096fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 209196fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 2092e6c8adcaSAl Viro __poll_t ret = 0; 209396fd7ce5SGreg Kroah-Hartman 20946131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_poll")) 209596fd7ce5SGreg Kroah-Hartman return 0; 209696fd7ce5SGreg Kroah-Hartman 209796fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2098e55afd11SPeter Hurley if (!ld) 2099e55afd11SPeter Hurley return hung_up_tty_poll(filp, wait); 210096fd7ce5SGreg Kroah-Hartman if (ld->ops->poll) 2101c961bfb1SPeter Hurley ret = ld->ops->poll(tty, filp, wait); 210296fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 210396fd7ce5SGreg Kroah-Hartman return ret; 210496fd7ce5SGreg Kroah-Hartman } 210596fd7ce5SGreg Kroah-Hartman 210696fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on) 210796fd7ce5SGreg Kroah-Hartman { 210896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 210996fd7ce5SGreg Kroah-Hartman unsigned long flags; 211096fd7ce5SGreg Kroah-Hartman int retval = 0; 211196fd7ce5SGreg Kroah-Hartman 21126131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_fasync")) 211396fd7ce5SGreg Kroah-Hartman goto out; 211496fd7ce5SGreg Kroah-Hartman 211596fd7ce5SGreg Kroah-Hartman retval = fasync_helper(fd, filp, on, &tty->fasync); 211696fd7ce5SGreg Kroah-Hartman if (retval <= 0) 211796fd7ce5SGreg Kroah-Hartman goto out; 211896fd7ce5SGreg Kroah-Hartman 211996fd7ce5SGreg Kroah-Hartman if (on) { 212096fd7ce5SGreg Kroah-Hartman enum pid_type type; 212196fd7ce5SGreg Kroah-Hartman struct pid *pid; 2122f6c8dbe6SPeter Hurley 212396fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 212496fd7ce5SGreg Kroah-Hartman if (tty->pgrp) { 212596fd7ce5SGreg Kroah-Hartman pid = tty->pgrp; 212696fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PGID; 212796fd7ce5SGreg Kroah-Hartman } else { 212896fd7ce5SGreg Kroah-Hartman pid = task_pid(current); 212901919134SEric W. Biederman type = PIDTYPE_TGID; 213096fd7ce5SGreg Kroah-Hartman } 213196fd7ce5SGreg Kroah-Hartman get_pid(pid); 213296fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 2133e0b93eddSJeff Layton __f_setown(filp, pid, type, 0); 213496fd7ce5SGreg Kroah-Hartman put_pid(pid); 2135e0b93eddSJeff Layton retval = 0; 213696fd7ce5SGreg Kroah-Hartman } 213796fd7ce5SGreg Kroah-Hartman out: 213896fd7ce5SGreg Kroah-Hartman return retval; 213996fd7ce5SGreg Kroah-Hartman } 214096fd7ce5SGreg Kroah-Hartman 214196fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on) 214296fd7ce5SGreg Kroah-Hartman { 214389c8d91eSAlan Cox struct tty_struct *tty = file_tty(filp); 2144a8f3a297SPeter Hurley int retval = -ENOTTY; 214589c8d91eSAlan Cox 214689c8d91eSAlan Cox tty_lock(tty); 2147a8f3a297SPeter Hurley if (!tty_hung_up_p(filp)) 214896fd7ce5SGreg Kroah-Hartman retval = __tty_fasync(fd, filp, on); 214989c8d91eSAlan Cox tty_unlock(tty); 215089c8d91eSAlan Cox 215196fd7ce5SGreg Kroah-Hartman return retval; 215296fd7ce5SGreg Kroah-Hartman } 215396fd7ce5SGreg Kroah-Hartman 215496fd7ce5SGreg Kroah-Hartman /** 215596fd7ce5SGreg Kroah-Hartman * tiocsti - fake input character 215696fd7ce5SGreg Kroah-Hartman * @tty: tty to fake input into 215796fd7ce5SGreg Kroah-Hartman * @p: pointer to character 215896fd7ce5SGreg Kroah-Hartman * 215996fd7ce5SGreg Kroah-Hartman * Fake input to a tty device. Does the necessary locking and 216096fd7ce5SGreg Kroah-Hartman * input management. 216196fd7ce5SGreg Kroah-Hartman * 216296fd7ce5SGreg Kroah-Hartman * FIXME: does not honour flow control ?? 216396fd7ce5SGreg Kroah-Hartman * 216496fd7ce5SGreg Kroah-Hartman * Locking: 2165137084bbSPeter Hurley * Called functions take tty_ldiscs_lock 216696fd7ce5SGreg Kroah-Hartman * current->signal->tty check is safe without locks 216796fd7ce5SGreg Kroah-Hartman * 216896fd7ce5SGreg Kroah-Hartman * FIXME: may race normal receive processing 216996fd7ce5SGreg Kroah-Hartman */ 217096fd7ce5SGreg Kroah-Hartman 217196fd7ce5SGreg Kroah-Hartman static int tiocsti(struct tty_struct *tty, char __user *p) 217296fd7ce5SGreg Kroah-Hartman { 217396fd7ce5SGreg Kroah-Hartman char ch, mbz = 0; 217496fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 217596fd7ce5SGreg Kroah-Hartman 217696fd7ce5SGreg Kroah-Hartman if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) 217796fd7ce5SGreg Kroah-Hartman return -EPERM; 217896fd7ce5SGreg Kroah-Hartman if (get_user(ch, p)) 217996fd7ce5SGreg Kroah-Hartman return -EFAULT; 218096fd7ce5SGreg Kroah-Hartman tty_audit_tiocsti(tty, ch); 218196fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2182e55afd11SPeter Hurley if (!ld) 2183e55afd11SPeter Hurley return -EIO; 218496fd7ce5SGreg Kroah-Hartman ld->ops->receive_buf(tty, &ch, &mbz, 1); 218596fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 218696fd7ce5SGreg Kroah-Hartman return 0; 218796fd7ce5SGreg Kroah-Hartman } 218896fd7ce5SGreg Kroah-Hartman 218996fd7ce5SGreg Kroah-Hartman /** 219096fd7ce5SGreg Kroah-Hartman * tiocgwinsz - implement window query ioctl 219196fd7ce5SGreg Kroah-Hartman * @tty; tty 219296fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 219396fd7ce5SGreg Kroah-Hartman * 219496fd7ce5SGreg Kroah-Hartman * Copies the kernel idea of the window size into the user buffer. 219596fd7ce5SGreg Kroah-Hartman * 2196dee4a0beSPeter Hurley * Locking: tty->winsize_mutex is taken to ensure the winsize data 219796fd7ce5SGreg Kroah-Hartman * is consistent. 219896fd7ce5SGreg Kroah-Hartman */ 219996fd7ce5SGreg Kroah-Hartman 220096fd7ce5SGreg Kroah-Hartman static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) 220196fd7ce5SGreg Kroah-Hartman { 220296fd7ce5SGreg Kroah-Hartman int err; 220396fd7ce5SGreg Kroah-Hartman 2204dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 220596fd7ce5SGreg Kroah-Hartman err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); 2206dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 220796fd7ce5SGreg Kroah-Hartman 220896fd7ce5SGreg Kroah-Hartman return err ? -EFAULT: 0; 220996fd7ce5SGreg Kroah-Hartman } 221096fd7ce5SGreg Kroah-Hartman 221196fd7ce5SGreg Kroah-Hartman /** 221296fd7ce5SGreg Kroah-Hartman * tty_do_resize - resize event 221396fd7ce5SGreg Kroah-Hartman * @tty: tty being resized 221496fd7ce5SGreg Kroah-Hartman * @rows: rows (character) 221596fd7ce5SGreg Kroah-Hartman * @cols: cols (character) 221696fd7ce5SGreg Kroah-Hartman * 221796fd7ce5SGreg Kroah-Hartman * Update the termios variables and send the necessary signals to 221896fd7ce5SGreg Kroah-Hartman * peform a terminal resize correctly 221996fd7ce5SGreg Kroah-Hartman */ 222096fd7ce5SGreg Kroah-Hartman 222196fd7ce5SGreg Kroah-Hartman int tty_do_resize(struct tty_struct *tty, struct winsize *ws) 222296fd7ce5SGreg Kroah-Hartman { 222396fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 222496fd7ce5SGreg Kroah-Hartman 222596fd7ce5SGreg Kroah-Hartman /* Lock the tty */ 2226dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 222796fd7ce5SGreg Kroah-Hartman if (!memcmp(ws, &tty->winsize, sizeof(*ws))) 222896fd7ce5SGreg Kroah-Hartman goto done; 222996fd7ce5SGreg Kroah-Hartman 22305b239542SPeter Hurley /* Signal the foreground process group */ 22315b239542SPeter Hurley pgrp = tty_get_pgrp(tty); 223296fd7ce5SGreg Kroah-Hartman if (pgrp) 223396fd7ce5SGreg Kroah-Hartman kill_pgrp(pgrp, SIGWINCH, 1); 223496fd7ce5SGreg Kroah-Hartman put_pid(pgrp); 223596fd7ce5SGreg Kroah-Hartman 223696fd7ce5SGreg Kroah-Hartman tty->winsize = *ws; 223796fd7ce5SGreg Kroah-Hartman done: 2238dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 223996fd7ce5SGreg Kroah-Hartman return 0; 224096fd7ce5SGreg Kroah-Hartman } 22414d334fd1SMartin Schwidefsky EXPORT_SYMBOL(tty_do_resize); 224296fd7ce5SGreg Kroah-Hartman 224396fd7ce5SGreg Kroah-Hartman /** 224496fd7ce5SGreg Kroah-Hartman * tiocswinsz - implement window size set ioctl 224596fd7ce5SGreg Kroah-Hartman * @tty; tty side of tty 224696fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 224796fd7ce5SGreg Kroah-Hartman * 224896fd7ce5SGreg Kroah-Hartman * Copies the user idea of the window size to the kernel. Traditionally 224996fd7ce5SGreg Kroah-Hartman * this is just advisory information but for the Linux console it 225096fd7ce5SGreg Kroah-Hartman * actually has driver level meaning and triggers a VC resize. 225196fd7ce5SGreg Kroah-Hartman * 225296fd7ce5SGreg Kroah-Hartman * Locking: 225325985edcSLucas De Marchi * Driver dependent. The default do_resize method takes the 225496fd7ce5SGreg Kroah-Hartman * tty termios mutex and ctrl_lock. The console takes its own lock 225596fd7ce5SGreg Kroah-Hartman * then calls into the default method. 225696fd7ce5SGreg Kroah-Hartman */ 225796fd7ce5SGreg Kroah-Hartman 225896fd7ce5SGreg Kroah-Hartman static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) 225996fd7ce5SGreg Kroah-Hartman { 226096fd7ce5SGreg Kroah-Hartman struct winsize tmp_ws; 226196fd7ce5SGreg Kroah-Hartman if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) 226296fd7ce5SGreg Kroah-Hartman return -EFAULT; 226396fd7ce5SGreg Kroah-Hartman 226496fd7ce5SGreg Kroah-Hartman if (tty->ops->resize) 226596fd7ce5SGreg Kroah-Hartman return tty->ops->resize(tty, &tmp_ws); 226696fd7ce5SGreg Kroah-Hartman else 226796fd7ce5SGreg Kroah-Hartman return tty_do_resize(tty, &tmp_ws); 226896fd7ce5SGreg Kroah-Hartman } 226996fd7ce5SGreg Kroah-Hartman 227096fd7ce5SGreg Kroah-Hartman /** 227196fd7ce5SGreg Kroah-Hartman * tioccons - allow admin to move logical console 227296fd7ce5SGreg Kroah-Hartman * @file: the file to become console 227396fd7ce5SGreg Kroah-Hartman * 227425985edcSLucas De Marchi * Allow the administrator to move the redirected console device 227596fd7ce5SGreg Kroah-Hartman * 227696fd7ce5SGreg Kroah-Hartman * Locking: uses redirect_lock to guard the redirect information 227796fd7ce5SGreg Kroah-Hartman */ 227896fd7ce5SGreg Kroah-Hartman 227996fd7ce5SGreg Kroah-Hartman static int tioccons(struct file *file) 228096fd7ce5SGreg Kroah-Hartman { 228196fd7ce5SGreg Kroah-Hartman if (!capable(CAP_SYS_ADMIN)) 228296fd7ce5SGreg Kroah-Hartman return -EPERM; 228396fd7ce5SGreg Kroah-Hartman if (file->f_op->write == redirected_tty_write) { 228496fd7ce5SGreg Kroah-Hartman struct file *f; 228596fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 228696fd7ce5SGreg Kroah-Hartman f = redirect; 228796fd7ce5SGreg Kroah-Hartman redirect = NULL; 228896fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 228996fd7ce5SGreg Kroah-Hartman if (f) 229096fd7ce5SGreg Kroah-Hartman fput(f); 229196fd7ce5SGreg Kroah-Hartman return 0; 229296fd7ce5SGreg Kroah-Hartman } 229396fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 229496fd7ce5SGreg Kroah-Hartman if (redirect) { 229596fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 229696fd7ce5SGreg Kroah-Hartman return -EBUSY; 229796fd7ce5SGreg Kroah-Hartman } 2298cb0942b8SAl Viro redirect = get_file(file); 229996fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 230096fd7ce5SGreg Kroah-Hartman return 0; 230196fd7ce5SGreg Kroah-Hartman } 230296fd7ce5SGreg Kroah-Hartman 230396fd7ce5SGreg Kroah-Hartman /** 230496fd7ce5SGreg Kroah-Hartman * tiocsetd - set line discipline 230596fd7ce5SGreg Kroah-Hartman * @tty: tty device 230696fd7ce5SGreg Kroah-Hartman * @p: pointer to user data 230796fd7ce5SGreg Kroah-Hartman * 230896fd7ce5SGreg Kroah-Hartman * Set the line discipline according to user request. 230996fd7ce5SGreg Kroah-Hartman * 231096fd7ce5SGreg Kroah-Hartman * Locking: see tty_set_ldisc, this function is just a helper 231196fd7ce5SGreg Kroah-Hartman */ 231296fd7ce5SGreg Kroah-Hartman 231396fd7ce5SGreg Kroah-Hartman static int tiocsetd(struct tty_struct *tty, int __user *p) 231496fd7ce5SGreg Kroah-Hartman { 2315c12da96fSPeter Hurley int disc; 231696fd7ce5SGreg Kroah-Hartman int ret; 231796fd7ce5SGreg Kroah-Hartman 2318c12da96fSPeter Hurley if (get_user(disc, p)) 231996fd7ce5SGreg Kroah-Hartman return -EFAULT; 232096fd7ce5SGreg Kroah-Hartman 2321c12da96fSPeter Hurley ret = tty_set_ldisc(tty, disc); 232296fd7ce5SGreg Kroah-Hartman 232396fd7ce5SGreg Kroah-Hartman return ret; 232496fd7ce5SGreg Kroah-Hartman } 232596fd7ce5SGreg Kroah-Hartman 232696fd7ce5SGreg Kroah-Hartman /** 23275c17c861SPeter Hurley * tiocgetd - get line discipline 23285c17c861SPeter Hurley * @tty: tty device 23295c17c861SPeter Hurley * @p: pointer to user data 23305c17c861SPeter Hurley * 23315c17c861SPeter Hurley * Retrieves the line discipline id directly from the ldisc. 23325c17c861SPeter Hurley * 23335c17c861SPeter Hurley * Locking: waits for ldisc reference (in case the line discipline 23345c17c861SPeter Hurley * is changing or the tty is being hungup) 23355c17c861SPeter Hurley */ 23365c17c861SPeter Hurley 23375c17c861SPeter Hurley static int tiocgetd(struct tty_struct *tty, int __user *p) 23385c17c861SPeter Hurley { 23395c17c861SPeter Hurley struct tty_ldisc *ld; 23405c17c861SPeter Hurley int ret; 23415c17c861SPeter Hurley 23425c17c861SPeter Hurley ld = tty_ldisc_ref_wait(tty); 2343e55afd11SPeter Hurley if (!ld) 2344e55afd11SPeter Hurley return -EIO; 23455c17c861SPeter Hurley ret = put_user(ld->ops->num, p); 23465c17c861SPeter Hurley tty_ldisc_deref(ld); 23475c17c861SPeter Hurley return ret; 23485c17c861SPeter Hurley } 23495c17c861SPeter Hurley 23505c17c861SPeter Hurley /** 235196fd7ce5SGreg Kroah-Hartman * send_break - performed time break 235296fd7ce5SGreg Kroah-Hartman * @tty: device to break on 235396fd7ce5SGreg Kroah-Hartman * @duration: timeout in mS 235496fd7ce5SGreg Kroah-Hartman * 235596fd7ce5SGreg Kroah-Hartman * Perform a timed break on hardware that lacks its own driver level 235696fd7ce5SGreg Kroah-Hartman * timed break functionality. 235796fd7ce5SGreg Kroah-Hartman * 235896fd7ce5SGreg Kroah-Hartman * Locking: 235996fd7ce5SGreg Kroah-Hartman * atomic_write_lock serializes 236096fd7ce5SGreg Kroah-Hartman * 236196fd7ce5SGreg Kroah-Hartman */ 236296fd7ce5SGreg Kroah-Hartman 236396fd7ce5SGreg Kroah-Hartman static int send_break(struct tty_struct *tty, unsigned int duration) 236496fd7ce5SGreg Kroah-Hartman { 236596fd7ce5SGreg Kroah-Hartman int retval; 236696fd7ce5SGreg Kroah-Hartman 236796fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl == NULL) 236896fd7ce5SGreg Kroah-Hartman return 0; 236996fd7ce5SGreg Kroah-Hartman 237096fd7ce5SGreg Kroah-Hartman if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) 237196fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, duration); 237296fd7ce5SGreg Kroah-Hartman else { 237396fd7ce5SGreg Kroah-Hartman /* Do the work ourselves */ 237496fd7ce5SGreg Kroah-Hartman if (tty_write_lock(tty, 0) < 0) 237596fd7ce5SGreg Kroah-Hartman return -EINTR; 237696fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, -1); 237796fd7ce5SGreg Kroah-Hartman if (retval) 237896fd7ce5SGreg Kroah-Hartman goto out; 237996fd7ce5SGreg Kroah-Hartman if (!signal_pending(current)) 238096fd7ce5SGreg Kroah-Hartman msleep_interruptible(duration); 238196fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, 0); 238296fd7ce5SGreg Kroah-Hartman out: 238396fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 238496fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 238596fd7ce5SGreg Kroah-Hartman retval = -EINTR; 238696fd7ce5SGreg Kroah-Hartman } 238796fd7ce5SGreg Kroah-Hartman return retval; 238896fd7ce5SGreg Kroah-Hartman } 238996fd7ce5SGreg Kroah-Hartman 239096fd7ce5SGreg Kroah-Hartman /** 239196fd7ce5SGreg Kroah-Hartman * tty_tiocmget - get modem status 239296fd7ce5SGreg Kroah-Hartman * @tty: tty device 239396fd7ce5SGreg Kroah-Hartman * @file: user file pointer 239496fd7ce5SGreg Kroah-Hartman * @p: pointer to result 239596fd7ce5SGreg Kroah-Hartman * 239696fd7ce5SGreg Kroah-Hartman * Obtain the modem status bits from the tty driver if the feature 239796fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 239896fd7ce5SGreg Kroah-Hartman * 239996fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 240096fd7ce5SGreg Kroah-Hartman */ 240196fd7ce5SGreg Kroah-Hartman 240260b33c13SAlan Cox static int tty_tiocmget(struct tty_struct *tty, int __user *p) 240396fd7ce5SGreg Kroah-Hartman { 240496fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 240596fd7ce5SGreg Kroah-Hartman 240696fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmget) { 240760b33c13SAlan Cox retval = tty->ops->tiocmget(tty); 240896fd7ce5SGreg Kroah-Hartman 240996fd7ce5SGreg Kroah-Hartman if (retval >= 0) 241096fd7ce5SGreg Kroah-Hartman retval = put_user(retval, p); 241196fd7ce5SGreg Kroah-Hartman } 241296fd7ce5SGreg Kroah-Hartman return retval; 241396fd7ce5SGreg Kroah-Hartman } 241496fd7ce5SGreg Kroah-Hartman 241596fd7ce5SGreg Kroah-Hartman /** 241696fd7ce5SGreg Kroah-Hartman * tty_tiocmset - set modem status 241796fd7ce5SGreg Kroah-Hartman * @tty: tty device 241896fd7ce5SGreg Kroah-Hartman * @cmd: command - clear bits, set bits or set all 241996fd7ce5SGreg Kroah-Hartman * @p: pointer to desired bits 242096fd7ce5SGreg Kroah-Hartman * 242196fd7ce5SGreg Kroah-Hartman * Set the modem status bits from the tty driver if the feature 242296fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 242396fd7ce5SGreg Kroah-Hartman * 242496fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 242596fd7ce5SGreg Kroah-Hartman */ 242696fd7ce5SGreg Kroah-Hartman 242720b9d177SAlan Cox static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, 242896fd7ce5SGreg Kroah-Hartman unsigned __user *p) 242996fd7ce5SGreg Kroah-Hartman { 243096fd7ce5SGreg Kroah-Hartman int retval; 243196fd7ce5SGreg Kroah-Hartman unsigned int set, clear, val; 243296fd7ce5SGreg Kroah-Hartman 243396fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmset == NULL) 243496fd7ce5SGreg Kroah-Hartman return -EINVAL; 243596fd7ce5SGreg Kroah-Hartman 243696fd7ce5SGreg Kroah-Hartman retval = get_user(val, p); 243796fd7ce5SGreg Kroah-Hartman if (retval) 243896fd7ce5SGreg Kroah-Hartman return retval; 243996fd7ce5SGreg Kroah-Hartman set = clear = 0; 244096fd7ce5SGreg Kroah-Hartman switch (cmd) { 244196fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 244296fd7ce5SGreg Kroah-Hartman set = val; 244396fd7ce5SGreg Kroah-Hartman break; 244496fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 244596fd7ce5SGreg Kroah-Hartman clear = val; 244696fd7ce5SGreg Kroah-Hartman break; 244796fd7ce5SGreg Kroah-Hartman case TIOCMSET: 244896fd7ce5SGreg Kroah-Hartman set = val; 244996fd7ce5SGreg Kroah-Hartman clear = ~val; 245096fd7ce5SGreg Kroah-Hartman break; 245196fd7ce5SGreg Kroah-Hartman } 245296fd7ce5SGreg Kroah-Hartman set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 245396fd7ce5SGreg Kroah-Hartman clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 245420b9d177SAlan Cox return tty->ops->tiocmset(tty, set, clear); 245596fd7ce5SGreg Kroah-Hartman } 245696fd7ce5SGreg Kroah-Hartman 245796fd7ce5SGreg Kroah-Hartman static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) 245896fd7ce5SGreg Kroah-Hartman { 245996fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 246096fd7ce5SGreg Kroah-Hartman struct serial_icounter_struct icount; 246196fd7ce5SGreg Kroah-Hartman memset(&icount, 0, sizeof(icount)); 246296fd7ce5SGreg Kroah-Hartman if (tty->ops->get_icount) 246396fd7ce5SGreg Kroah-Hartman retval = tty->ops->get_icount(tty, &icount); 246496fd7ce5SGreg Kroah-Hartman if (retval != 0) 246596fd7ce5SGreg Kroah-Hartman return retval; 246696fd7ce5SGreg Kroah-Hartman if (copy_to_user(arg, &icount, sizeof(icount))) 246796fd7ce5SGreg Kroah-Hartman return -EFAULT; 246896fd7ce5SGreg Kroah-Hartman return 0; 246996fd7ce5SGreg Kroah-Hartman } 247096fd7ce5SGreg Kroah-Hartman 24712f46a2c1SAl Viro static int tty_tiocsserial(struct tty_struct *tty, struct serial_struct __user *ss) 24728a8ae62fSJiri Slaby { 24738a8ae62fSJiri Slaby static DEFINE_RATELIMIT_STATE(depr_flags, 24748a8ae62fSJiri Slaby DEFAULT_RATELIMIT_INTERVAL, 24758a8ae62fSJiri Slaby DEFAULT_RATELIMIT_BURST); 24768a8ae62fSJiri Slaby char comm[TASK_COMM_LEN]; 24772f46a2c1SAl Viro struct serial_struct v; 24788a8ae62fSJiri Slaby int flags; 24798a8ae62fSJiri Slaby 24802f46a2c1SAl Viro if (copy_from_user(&v, ss, sizeof(struct serial_struct))) 24812f46a2c1SAl Viro return -EFAULT; 24828a8ae62fSJiri Slaby 24832f46a2c1SAl Viro flags = v.flags & ASYNC_DEPRECATED; 24848a8ae62fSJiri Slaby 24858a8ae62fSJiri Slaby if (flags && __ratelimit(&depr_flags)) 2486d437fa91SJoe Perches pr_warn("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", 24878a8ae62fSJiri Slaby __func__, get_task_comm(comm, current), flags); 24882f46a2c1SAl Viro if (!tty->ops->set_serial) 2489930236a3SAl Viro return -ENOTTY; 24902f46a2c1SAl Viro return tty->ops->set_serial(tty, &v); 24912f46a2c1SAl Viro } 24922f46a2c1SAl Viro 24932f46a2c1SAl Viro static int tty_tiocgserial(struct tty_struct *tty, struct serial_struct __user *ss) 24942f46a2c1SAl Viro { 24952f46a2c1SAl Viro struct serial_struct v; 24962f46a2c1SAl Viro int err; 24972f46a2c1SAl Viro 24982f46a2c1SAl Viro memset(&v, 0, sizeof(struct serial_struct)); 24992f46a2c1SAl Viro if (!tty->ops->get_serial) 2500930236a3SAl Viro return -ENOTTY; 25012f46a2c1SAl Viro err = tty->ops->get_serial(tty, &v); 25022f46a2c1SAl Viro if (!err && copy_to_user(ss, &v, sizeof(struct serial_struct))) 25032f46a2c1SAl Viro err = -EFAULT; 25042f46a2c1SAl Viro return err; 25058a8ae62fSJiri Slaby } 25068a8ae62fSJiri Slaby 25078f166e00SPeter Hurley /* 25088f166e00SPeter Hurley * if pty, return the slave side (real_tty) 25098f166e00SPeter Hurley * otherwise, return self 25108f166e00SPeter Hurley */ 25118f166e00SPeter Hurley static struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) 251296fd7ce5SGreg Kroah-Hartman { 251396fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 251496fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_MASTER) 251596fd7ce5SGreg Kroah-Hartman tty = tty->link; 251696fd7ce5SGreg Kroah-Hartman return tty; 251796fd7ce5SGreg Kroah-Hartman } 251896fd7ce5SGreg Kroah-Hartman 251996fd7ce5SGreg Kroah-Hartman /* 252096fd7ce5SGreg Kroah-Hartman * Split this up, as gcc can choke on it otherwise.. 252196fd7ce5SGreg Kroah-Hartman */ 252296fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 252396fd7ce5SGreg Kroah-Hartman { 252496fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 252596fd7ce5SGreg Kroah-Hartman struct tty_struct *real_tty; 252696fd7ce5SGreg Kroah-Hartman void __user *p = (void __user *)arg; 252796fd7ce5SGreg Kroah-Hartman int retval; 252896fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 252996fd7ce5SGreg Kroah-Hartman 25306131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 253196fd7ce5SGreg Kroah-Hartman return -EINVAL; 253296fd7ce5SGreg Kroah-Hartman 253396fd7ce5SGreg Kroah-Hartman real_tty = tty_pair_get_tty(tty); 253496fd7ce5SGreg Kroah-Hartman 253596fd7ce5SGreg Kroah-Hartman /* 253696fd7ce5SGreg Kroah-Hartman * Factor out some common prep work 253796fd7ce5SGreg Kroah-Hartman */ 253896fd7ce5SGreg Kroah-Hartman switch (cmd) { 253996fd7ce5SGreg Kroah-Hartman case TIOCSETD: 254096fd7ce5SGreg Kroah-Hartman case TIOCSBRK: 254196fd7ce5SGreg Kroah-Hartman case TIOCCBRK: 254296fd7ce5SGreg Kroah-Hartman case TCSBRK: 254396fd7ce5SGreg Kroah-Hartman case TCSBRKP: 254496fd7ce5SGreg Kroah-Hartman retval = tty_check_change(tty); 254596fd7ce5SGreg Kroah-Hartman if (retval) 254696fd7ce5SGreg Kroah-Hartman return retval; 254796fd7ce5SGreg Kroah-Hartman if (cmd != TIOCCBRK) { 254896fd7ce5SGreg Kroah-Hartman tty_wait_until_sent(tty, 0); 254996fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 255096fd7ce5SGreg Kroah-Hartman return -EINTR; 255196fd7ce5SGreg Kroah-Hartman } 255296fd7ce5SGreg Kroah-Hartman break; 255396fd7ce5SGreg Kroah-Hartman } 255496fd7ce5SGreg Kroah-Hartman 255596fd7ce5SGreg Kroah-Hartman /* 255696fd7ce5SGreg Kroah-Hartman * Now do the stuff. 255796fd7ce5SGreg Kroah-Hartman */ 255896fd7ce5SGreg Kroah-Hartman switch (cmd) { 255996fd7ce5SGreg Kroah-Hartman case TIOCSTI: 256096fd7ce5SGreg Kroah-Hartman return tiocsti(tty, p); 256196fd7ce5SGreg Kroah-Hartman case TIOCGWINSZ: 256296fd7ce5SGreg Kroah-Hartman return tiocgwinsz(real_tty, p); 256396fd7ce5SGreg Kroah-Hartman case TIOCSWINSZ: 256496fd7ce5SGreg Kroah-Hartman return tiocswinsz(real_tty, p); 256596fd7ce5SGreg Kroah-Hartman case TIOCCONS: 256696fd7ce5SGreg Kroah-Hartman return real_tty != tty ? -EINVAL : tioccons(file); 256796fd7ce5SGreg Kroah-Hartman case TIOCEXCL: 256896fd7ce5SGreg Kroah-Hartman set_bit(TTY_EXCLUSIVE, &tty->flags); 256996fd7ce5SGreg Kroah-Hartman return 0; 257096fd7ce5SGreg Kroah-Hartman case TIOCNXCL: 257196fd7ce5SGreg Kroah-Hartman clear_bit(TTY_EXCLUSIVE, &tty->flags); 257296fd7ce5SGreg Kroah-Hartman return 0; 257384fd7bdfSCyrill Gorcunov case TIOCGEXCL: 257484fd7bdfSCyrill Gorcunov { 257584fd7bdfSCyrill Gorcunov int excl = test_bit(TTY_EXCLUSIVE, &tty->flags); 257684fd7bdfSCyrill Gorcunov return put_user(excl, (int __user *)p); 257784fd7bdfSCyrill Gorcunov } 257896fd7ce5SGreg Kroah-Hartman case TIOCGETD: 25795c17c861SPeter Hurley return tiocgetd(tty, p); 258096fd7ce5SGreg Kroah-Hartman case TIOCSETD: 258196fd7ce5SGreg Kroah-Hartman return tiocsetd(tty, p); 25823c95c985SKay Sievers case TIOCVHANGUP: 25833c95c985SKay Sievers if (!capable(CAP_SYS_ADMIN)) 25843c95c985SKay Sievers return -EPERM; 25853c95c985SKay Sievers tty_vhangup(tty); 25863c95c985SKay Sievers return 0; 2587b7b8de08SWerner Fink case TIOCGDEV: 2588b7b8de08SWerner Fink { 2589b7b8de08SWerner Fink unsigned int ret = new_encode_dev(tty_devnum(real_tty)); 2590b7b8de08SWerner Fink return put_user(ret, (unsigned int __user *)p); 2591b7b8de08SWerner Fink } 259296fd7ce5SGreg Kroah-Hartman /* 259396fd7ce5SGreg Kroah-Hartman * Break handling 259496fd7ce5SGreg Kroah-Hartman */ 259596fd7ce5SGreg Kroah-Hartman case TIOCSBRK: /* Turn break on, unconditionally */ 259696fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 259796fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, -1); 259896fd7ce5SGreg Kroah-Hartman return 0; 259996fd7ce5SGreg Kroah-Hartman case TIOCCBRK: /* Turn break off, unconditionally */ 260096fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 260196fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, 0); 260296fd7ce5SGreg Kroah-Hartman return 0; 260396fd7ce5SGreg Kroah-Hartman case TCSBRK: /* SVID version: non-zero arg --> no break */ 260496fd7ce5SGreg Kroah-Hartman /* non-zero arg means wait for all output data 260596fd7ce5SGreg Kroah-Hartman * to be sent (performed above) but don't send break. 260696fd7ce5SGreg Kroah-Hartman * This is used by the tcdrain() termios function. 260796fd7ce5SGreg Kroah-Hartman */ 260896fd7ce5SGreg Kroah-Hartman if (!arg) 260996fd7ce5SGreg Kroah-Hartman return send_break(tty, 250); 261096fd7ce5SGreg Kroah-Hartman return 0; 261196fd7ce5SGreg Kroah-Hartman case TCSBRKP: /* support for POSIX tcsendbreak() */ 261296fd7ce5SGreg Kroah-Hartman return send_break(tty, arg ? arg*100 : 250); 261396fd7ce5SGreg Kroah-Hartman 261496fd7ce5SGreg Kroah-Hartman case TIOCMGET: 261560b33c13SAlan Cox return tty_tiocmget(tty, p); 261696fd7ce5SGreg Kroah-Hartman case TIOCMSET: 261796fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 261896fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 261920b9d177SAlan Cox return tty_tiocmset(tty, cmd, p); 262096fd7ce5SGreg Kroah-Hartman case TIOCGICOUNT: 2621a3096199SAl Viro return tty_tiocgicount(tty, p); 262296fd7ce5SGreg Kroah-Hartman case TCFLSH: 262396fd7ce5SGreg Kroah-Hartman switch (arg) { 262496fd7ce5SGreg Kroah-Hartman case TCIFLUSH: 262596fd7ce5SGreg Kroah-Hartman case TCIOFLUSH: 262696fd7ce5SGreg Kroah-Hartman /* flush tty buffer and allow ldisc to process ioctl */ 262786c80a8eSPeter Hurley tty_buffer_flush(tty, NULL); 262896fd7ce5SGreg Kroah-Hartman break; 262996fd7ce5SGreg Kroah-Hartman } 263096fd7ce5SGreg Kroah-Hartman break; 26318a8ae62fSJiri Slaby case TIOCSSERIAL: 2632930236a3SAl Viro return tty_tiocsserial(tty, p); 26332f46a2c1SAl Viro case TIOCGSERIAL: 2634930236a3SAl Viro return tty_tiocgserial(tty, p); 2635311fc65cSEric W. Biederman case TIOCGPTPEER: 2636311fc65cSEric W. Biederman /* Special because the struct file is needed */ 2637311fc65cSEric W. Biederman return ptm_open_peer(file, tty, (int)arg); 2638a1235b3eSNicolas Pitre default: 2639a1235b3eSNicolas Pitre retval = tty_jobctrl_ioctl(tty, real_tty, file, cmd, arg); 2640a1235b3eSNicolas Pitre if (retval != -ENOIOCTLCMD) 2641a1235b3eSNicolas Pitre return retval; 264296fd7ce5SGreg Kroah-Hartman } 264396fd7ce5SGreg Kroah-Hartman if (tty->ops->ioctl) { 2644c961bfb1SPeter Hurley retval = tty->ops->ioctl(tty, cmd, arg); 264596fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 264696fd7ce5SGreg Kroah-Hartman return retval; 264796fd7ce5SGreg Kroah-Hartman } 264896fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2649e55afd11SPeter Hurley if (!ld) 2650e55afd11SPeter Hurley return hung_up_tty_ioctl(file, cmd, arg); 265196fd7ce5SGreg Kroah-Hartman retval = -EINVAL; 265296fd7ce5SGreg Kroah-Hartman if (ld->ops->ioctl) { 265396fd7ce5SGreg Kroah-Hartman retval = ld->ops->ioctl(tty, file, cmd, arg); 265496fd7ce5SGreg Kroah-Hartman if (retval == -ENOIOCTLCMD) 2655bbb63c51SWanlong Gao retval = -ENOTTY; 265696fd7ce5SGreg Kroah-Hartman } 265796fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 265896fd7ce5SGreg Kroah-Hartman return retval; 265996fd7ce5SGreg Kroah-Hartman } 266096fd7ce5SGreg Kroah-Hartman 266196fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 266277654350SAl Viro 266377654350SAl Viro struct serial_struct32 { 266477654350SAl Viro compat_int_t type; 266577654350SAl Viro compat_int_t line; 266677654350SAl Viro compat_uint_t port; 266777654350SAl Viro compat_int_t irq; 266877654350SAl Viro compat_int_t flags; 266977654350SAl Viro compat_int_t xmit_fifo_size; 267077654350SAl Viro compat_int_t custom_divisor; 267177654350SAl Viro compat_int_t baud_base; 267277654350SAl Viro unsigned short close_delay; 267377654350SAl Viro char io_type; 267477654350SAl Viro char reserved_char[1]; 267577654350SAl Viro compat_int_t hub6; 267677654350SAl Viro unsigned short closing_wait; /* time to wait before closing */ 267777654350SAl Viro unsigned short closing_wait2; /* no longer used... */ 267877654350SAl Viro compat_uint_t iomem_base; 267977654350SAl Viro unsigned short iomem_reg_shift; 268077654350SAl Viro unsigned int port_high; 268177654350SAl Viro /* compat_ulong_t iomap_base FIXME */ 268277654350SAl Viro compat_int_t reserved[1]; 268377654350SAl Viro }; 268477654350SAl Viro 268577654350SAl Viro static int compat_tty_tiocsserial(struct tty_struct *tty, 268677654350SAl Viro struct serial_struct32 __user *ss) 268777654350SAl Viro { 268877654350SAl Viro static DEFINE_RATELIMIT_STATE(depr_flags, 268977654350SAl Viro DEFAULT_RATELIMIT_INTERVAL, 269077654350SAl Viro DEFAULT_RATELIMIT_BURST); 269177654350SAl Viro char comm[TASK_COMM_LEN]; 269277654350SAl Viro struct serial_struct32 v32; 269377654350SAl Viro struct serial_struct v; 269477654350SAl Viro int flags; 269577654350SAl Viro 269677654350SAl Viro if (copy_from_user(&v32, ss, sizeof(struct serial_struct32))) 269777654350SAl Viro return -EFAULT; 269877654350SAl Viro 269977654350SAl Viro memcpy(&v, &v32, offsetof(struct serial_struct32, iomem_base)); 270077654350SAl Viro v.iomem_base = compat_ptr(v32.iomem_base); 270177654350SAl Viro v.iomem_reg_shift = v32.iomem_reg_shift; 270277654350SAl Viro v.port_high = v32.port_high; 270377654350SAl Viro v.iomap_base = 0; 270477654350SAl Viro 270577654350SAl Viro flags = v.flags & ASYNC_DEPRECATED; 270677654350SAl Viro 270777654350SAl Viro if (flags && __ratelimit(&depr_flags)) 270877654350SAl Viro pr_warn("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", 270977654350SAl Viro __func__, get_task_comm(comm, current), flags); 271077654350SAl Viro if (!tty->ops->set_serial) 271177654350SAl Viro return -ENOTTY; 271277654350SAl Viro return tty->ops->set_serial(tty, &v); 271377654350SAl Viro } 271477654350SAl Viro 271577654350SAl Viro static int compat_tty_tiocgserial(struct tty_struct *tty, 271677654350SAl Viro struct serial_struct32 __user *ss) 271777654350SAl Viro { 271877654350SAl Viro struct serial_struct32 v32; 271977654350SAl Viro struct serial_struct v; 272077654350SAl Viro int err; 272177654350SAl Viro memset(&v, 0, sizeof(struct serial_struct)); 272277654350SAl Viro 272377654350SAl Viro if (!tty->ops->set_serial) 272477654350SAl Viro return -ENOTTY; 272577654350SAl Viro err = tty->ops->get_serial(tty, &v); 272677654350SAl Viro if (!err) { 272777654350SAl Viro memcpy(&v32, &v, offsetof(struct serial_struct32, iomem_base)); 272877654350SAl Viro v32.iomem_base = (unsigned long)v.iomem_base >> 32 ? 272977654350SAl Viro 0xfffffff : ptr_to_compat(v.iomem_base); 273077654350SAl Viro v32.iomem_reg_shift = v.iomem_reg_shift; 273177654350SAl Viro v32.port_high = v.port_high; 273277654350SAl Viro if (copy_to_user(ss, &v32, sizeof(struct serial_struct32))) 273377654350SAl Viro err = -EFAULT; 273477654350SAl Viro } 273577654350SAl Viro return err; 273677654350SAl Viro } 273796fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 273896fd7ce5SGreg Kroah-Hartman unsigned long arg) 273996fd7ce5SGreg Kroah-Hartman { 274096fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 274196fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 274296fd7ce5SGreg Kroah-Hartman int retval = -ENOIOCTLCMD; 274396fd7ce5SGreg Kroah-Hartman 2744e2112038SAl Viro switch (cmd) { 2745e2112038SAl Viro case TIOCSTI: 2746e2112038SAl Viro case TIOCGWINSZ: 2747e2112038SAl Viro case TIOCSWINSZ: 2748e2112038SAl Viro case TIOCGEXCL: 2749e2112038SAl Viro case TIOCGETD: 2750e2112038SAl Viro case TIOCSETD: 2751e2112038SAl Viro case TIOCGDEV: 2752e2112038SAl Viro case TIOCMGET: 2753e2112038SAl Viro case TIOCMSET: 2754e2112038SAl Viro case TIOCMBIC: 2755e2112038SAl Viro case TIOCMBIS: 2756e2112038SAl Viro case TIOCGICOUNT: 2757e2112038SAl Viro case TIOCGPGRP: 2758e2112038SAl Viro case TIOCSPGRP: 2759e2112038SAl Viro case TIOCGSID: 2760e2112038SAl Viro case TIOCSERGETLSR: 2761e2112038SAl Viro case TIOCGRS485: 2762e2112038SAl Viro case TIOCSRS485: 2763e2112038SAl Viro #ifdef TIOCGETP 2764e2112038SAl Viro case TIOCGETP: 2765e2112038SAl Viro case TIOCSETP: 2766e2112038SAl Viro case TIOCSETN: 2767e2112038SAl Viro #endif 2768e2112038SAl Viro #ifdef TIOCGETC 2769e2112038SAl Viro case TIOCGETC: 2770e2112038SAl Viro case TIOCSETC: 2771e2112038SAl Viro #endif 2772e2112038SAl Viro #ifdef TIOCGLTC 2773e2112038SAl Viro case TIOCGLTC: 2774e2112038SAl Viro case TIOCSLTC: 2775e2112038SAl Viro #endif 2776e2112038SAl Viro case TCSETSF: 2777e2112038SAl Viro case TCSETSW: 2778e2112038SAl Viro case TCSETS: 2779e2112038SAl Viro case TCGETS: 2780e2112038SAl Viro #ifdef TCGETS2 2781e2112038SAl Viro case TCGETS2: 2782e2112038SAl Viro case TCSETSF2: 2783e2112038SAl Viro case TCSETSW2: 2784e2112038SAl Viro case TCSETS2: 2785e2112038SAl Viro #endif 2786e2112038SAl Viro case TCGETA: 2787e2112038SAl Viro case TCSETAF: 2788e2112038SAl Viro case TCSETAW: 2789e2112038SAl Viro case TCSETA: 2790e2112038SAl Viro case TIOCGLCKTRMIOS: 2791e2112038SAl Viro case TIOCSLCKTRMIOS: 2792e2112038SAl Viro #ifdef TCGETX 2793e2112038SAl Viro case TCGETX: 2794e2112038SAl Viro case TCSETX: 2795e2112038SAl Viro case TCSETXW: 2796e2112038SAl Viro case TCSETXF: 2797e2112038SAl Viro #endif 2798e2112038SAl Viro case TIOCGSOFTCAR: 2799e2112038SAl Viro case TIOCSSOFTCAR: 2800e2112038SAl Viro return tty_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); 2801e2112038SAl Viro case TIOCCONS: 2802e2112038SAl Viro case TIOCEXCL: 2803e2112038SAl Viro case TIOCNXCL: 2804e2112038SAl Viro case TIOCVHANGUP: 2805e2112038SAl Viro case TIOCSBRK: 2806e2112038SAl Viro case TIOCCBRK: 2807e2112038SAl Viro case TCSBRK: 2808e2112038SAl Viro case TCSBRKP: 2809e2112038SAl Viro case TCFLSH: 2810e2112038SAl Viro case TIOCGPTPEER: 2811e2112038SAl Viro case TIOCNOTTY: 2812e2112038SAl Viro case TIOCSCTTY: 2813e2112038SAl Viro case TCXONC: 2814e2112038SAl Viro case TIOCMIWAIT: 2815e2112038SAl Viro case TIOCSERCONFIG: 2816e2112038SAl Viro return tty_ioctl(file, cmd, arg); 2817e2112038SAl Viro } 2818e2112038SAl Viro 28196131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 282096fd7ce5SGreg Kroah-Hartman return -EINVAL; 282196fd7ce5SGreg Kroah-Hartman 282277654350SAl Viro switch (cmd) { 282377654350SAl Viro case TIOCSSERIAL: 282477654350SAl Viro return compat_tty_tiocsserial(tty, compat_ptr(arg)); 282577654350SAl Viro case TIOCGSERIAL: 282677654350SAl Viro return compat_tty_tiocgserial(tty, compat_ptr(arg)); 282777654350SAl Viro } 282896fd7ce5SGreg Kroah-Hartman if (tty->ops->compat_ioctl) { 2829c961bfb1SPeter Hurley retval = tty->ops->compat_ioctl(tty, cmd, arg); 283096fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 283196fd7ce5SGreg Kroah-Hartman return retval; 283296fd7ce5SGreg Kroah-Hartman } 283396fd7ce5SGreg Kroah-Hartman 283496fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2835e55afd11SPeter Hurley if (!ld) 2836e55afd11SPeter Hurley return hung_up_tty_compat_ioctl(file, cmd, arg); 283796fd7ce5SGreg Kroah-Hartman if (ld->ops->compat_ioctl) 283896fd7ce5SGreg Kroah-Hartman retval = ld->ops->compat_ioctl(tty, file, cmd, arg); 2839f0193d3eSAl Viro if (retval == -ENOIOCTLCMD && ld->ops->ioctl) 2840f0193d3eSAl Viro retval = ld->ops->ioctl(tty, file, 2841f0193d3eSAl Viro (unsigned long)compat_ptr(cmd), arg); 284296fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 284396fd7ce5SGreg Kroah-Hartman 284496fd7ce5SGreg Kroah-Hartman return retval; 284596fd7ce5SGreg Kroah-Hartman } 284696fd7ce5SGreg Kroah-Hartman #endif 284796fd7ce5SGreg Kroah-Hartman 2848c3c073f8SAl Viro static int this_tty(const void *t, struct file *file, unsigned fd) 2849c3c073f8SAl Viro { 2850c3c073f8SAl Viro if (likely(file->f_op->read != tty_read)) 2851c3c073f8SAl Viro return 0; 2852c3c073f8SAl Viro return file_tty(file) != t ? 0 : fd + 1; 2853c3c073f8SAl Viro } 2854c3c073f8SAl Viro 285596fd7ce5SGreg Kroah-Hartman /* 285696fd7ce5SGreg Kroah-Hartman * This implements the "Secure Attention Key" --- the idea is to 285796fd7ce5SGreg Kroah-Hartman * prevent trojan horses by killing all processes associated with this 285896fd7ce5SGreg Kroah-Hartman * tty when the user hits the "Secure Attention Key". Required for 285996fd7ce5SGreg Kroah-Hartman * super-paranoid applications --- see the Orange Book for more details. 286096fd7ce5SGreg Kroah-Hartman * 286196fd7ce5SGreg Kroah-Hartman * This code could be nicer; ideally it should send a HUP, wait a few 286296fd7ce5SGreg Kroah-Hartman * seconds, then send a INT, and then a KILL signal. But you then 286396fd7ce5SGreg Kroah-Hartman * have to coordinate with the init process, since all processes associated 286496fd7ce5SGreg Kroah-Hartman * with the current tty must be dead before the new getty is allowed 286596fd7ce5SGreg Kroah-Hartman * to spawn. 286696fd7ce5SGreg Kroah-Hartman * 286796fd7ce5SGreg Kroah-Hartman * Now, if it would be correct ;-/ The current code has a nasty hole - 286896fd7ce5SGreg Kroah-Hartman * it doesn't catch files in flight. We may send the descriptor to ourselves 286996fd7ce5SGreg Kroah-Hartman * via AF_UNIX socket, close it and later fetch from socket. FIXME. 287096fd7ce5SGreg Kroah-Hartman * 287196fd7ce5SGreg Kroah-Hartman * Nasty bug: do_SAK is being called in interrupt context. This can 287296fd7ce5SGreg Kroah-Hartman * deadlock. We punt it up to process context. AKPM - 16Mar2001 287396fd7ce5SGreg Kroah-Hartman */ 287496fd7ce5SGreg Kroah-Hartman void __do_SAK(struct tty_struct *tty) 287596fd7ce5SGreg Kroah-Hartman { 287696fd7ce5SGreg Kroah-Hartman #ifdef TTY_SOFT_SAK 287796fd7ce5SGreg Kroah-Hartman tty_hangup(tty); 287896fd7ce5SGreg Kroah-Hartman #else 287996fd7ce5SGreg Kroah-Hartman struct task_struct *g, *p; 288096fd7ce5SGreg Kroah-Hartman struct pid *session; 288196fd7ce5SGreg Kroah-Hartman int i; 288296fd7ce5SGreg Kroah-Hartman 288396fd7ce5SGreg Kroah-Hartman if (!tty) 288496fd7ce5SGreg Kroah-Hartman return; 288596fd7ce5SGreg Kroah-Hartman session = tty->session; 288696fd7ce5SGreg Kroah-Hartman 288796fd7ce5SGreg Kroah-Hartman tty_ldisc_flush(tty); 288896fd7ce5SGreg Kroah-Hartman 288996fd7ce5SGreg Kroah-Hartman tty_driver_flush_buffer(tty); 289096fd7ce5SGreg Kroah-Hartman 289196fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 289296fd7ce5SGreg Kroah-Hartman /* Kill the entire session */ 289396fd7ce5SGreg Kroah-Hartman do_each_pid_task(session, PIDTYPE_SID, p) { 28949b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by session\n", 289596fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 2896a8ebd171SEric W. Biederman group_send_sig_info(SIGKILL, SEND_SIG_PRIV, p, PIDTYPE_SID); 289796fd7ce5SGreg Kroah-Hartman } while_each_pid_task(session, PIDTYPE_SID, p); 28989b42bb75SPeter Hurley 28999b42bb75SPeter Hurley /* Now kill any processes that happen to have the tty open */ 290096fd7ce5SGreg Kroah-Hartman do_each_thread(g, p) { 290196fd7ce5SGreg Kroah-Hartman if (p->signal->tty == tty) { 29029b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by controlling tty\n", 290396fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 2904a8ebd171SEric W. Biederman group_send_sig_info(SIGKILL, SEND_SIG_PRIV, p, PIDTYPE_SID); 290596fd7ce5SGreg Kroah-Hartman continue; 290696fd7ce5SGreg Kroah-Hartman } 290796fd7ce5SGreg Kroah-Hartman task_lock(p); 2908c3c073f8SAl Viro i = iterate_fd(p->files, 0, this_tty, tty); 2909c3c073f8SAl Viro if (i != 0) { 29109b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by fd#%d\n", 2911c3c073f8SAl Viro task_pid_nr(p), p->comm, i - 1); 2912a8ebd171SEric W. Biederman group_send_sig_info(SIGKILL, SEND_SIG_PRIV, p, PIDTYPE_SID); 291396fd7ce5SGreg Kroah-Hartman } 291496fd7ce5SGreg Kroah-Hartman task_unlock(p); 291596fd7ce5SGreg Kroah-Hartman } while_each_thread(g, p); 291696fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 291796fd7ce5SGreg Kroah-Hartman #endif 291896fd7ce5SGreg Kroah-Hartman } 291996fd7ce5SGreg Kroah-Hartman 292096fd7ce5SGreg Kroah-Hartman static void do_SAK_work(struct work_struct *work) 292196fd7ce5SGreg Kroah-Hartman { 292296fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 292396fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, SAK_work); 292496fd7ce5SGreg Kroah-Hartman __do_SAK(tty); 292596fd7ce5SGreg Kroah-Hartman } 292696fd7ce5SGreg Kroah-Hartman 292796fd7ce5SGreg Kroah-Hartman /* 292896fd7ce5SGreg Kroah-Hartman * The tq handling here is a little racy - tty->SAK_work may already be queued. 292996fd7ce5SGreg Kroah-Hartman * Fortunately we don't need to worry, because if ->SAK_work is already queued, 293096fd7ce5SGreg Kroah-Hartman * the values which we write to it will be identical to the values which it 293196fd7ce5SGreg Kroah-Hartman * already has. --akpm 293296fd7ce5SGreg Kroah-Hartman */ 293396fd7ce5SGreg Kroah-Hartman void do_SAK(struct tty_struct *tty) 293496fd7ce5SGreg Kroah-Hartman { 293596fd7ce5SGreg Kroah-Hartman if (!tty) 293696fd7ce5SGreg Kroah-Hartman return; 293796fd7ce5SGreg Kroah-Hartman schedule_work(&tty->SAK_work); 293896fd7ce5SGreg Kroah-Hartman } 293996fd7ce5SGreg Kroah-Hartman 294096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(do_SAK); 294196fd7ce5SGreg Kroah-Hartman 29426e9430acSGreg Kroah-Hartman static int dev_match_devt(struct device *dev, const void *data) 294396fd7ce5SGreg Kroah-Hartman { 29446e9430acSGreg Kroah-Hartman const dev_t *devt = data; 294596fd7ce5SGreg Kroah-Hartman return dev->devt == *devt; 294696fd7ce5SGreg Kroah-Hartman } 294796fd7ce5SGreg Kroah-Hartman 294896fd7ce5SGreg Kroah-Hartman /* Must put_device() after it's unused! */ 294996fd7ce5SGreg Kroah-Hartman static struct device *tty_get_device(struct tty_struct *tty) 295096fd7ce5SGreg Kroah-Hartman { 295196fd7ce5SGreg Kroah-Hartman dev_t devt = tty_devnum(tty); 295296fd7ce5SGreg Kroah-Hartman return class_find_device(tty_class, NULL, &devt, dev_match_devt); 295396fd7ce5SGreg Kroah-Hartman } 295496fd7ce5SGreg Kroah-Hartman 295596fd7ce5SGreg Kroah-Hartman 295696fd7ce5SGreg Kroah-Hartman /** 29572c964a2fSRasmus Villemoes * alloc_tty_struct 295896fd7ce5SGreg Kroah-Hartman * 29592c964a2fSRasmus Villemoes * This subroutine allocates and initializes a tty structure. 296096fd7ce5SGreg Kroah-Hartman * 29612c964a2fSRasmus Villemoes * Locking: none - tty in question is not exposed at this point 296296fd7ce5SGreg Kroah-Hartman */ 296396fd7ce5SGreg Kroah-Hartman 29642c964a2fSRasmus Villemoes struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx) 296596fd7ce5SGreg Kroah-Hartman { 29662c964a2fSRasmus Villemoes struct tty_struct *tty; 29672c964a2fSRasmus Villemoes 29682c964a2fSRasmus Villemoes tty = kzalloc(sizeof(*tty), GFP_KERNEL); 29692c964a2fSRasmus Villemoes if (!tty) 29702c964a2fSRasmus Villemoes return NULL; 29712c964a2fSRasmus Villemoes 297296fd7ce5SGreg Kroah-Hartman kref_init(&tty->kref); 297396fd7ce5SGreg Kroah-Hartman tty->magic = TTY_MAGIC; 2974903f9db1STetsuo Handa if (tty_ldisc_init(tty)) { 2975903f9db1STetsuo Handa kfree(tty); 2976903f9db1STetsuo Handa return NULL; 2977903f9db1STetsuo Handa } 297896fd7ce5SGreg Kroah-Hartman tty->session = NULL; 297996fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 298089c8d91eSAlan Cox mutex_init(&tty->legacy_mutex); 2981d8c1f929SPeter Hurley mutex_init(&tty->throttle_mutex); 29826a1c0680SPeter Hurley init_rwsem(&tty->termios_rwsem); 2983dee4a0beSPeter Hurley mutex_init(&tty->winsize_mutex); 298436697529SPeter Hurley init_ldsem(&tty->ldisc_sem); 298596fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->write_wait); 298696fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->read_wait); 298796fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, do_tty_hangup); 298896fd7ce5SGreg Kroah-Hartman mutex_init(&tty->atomic_write_lock); 298996fd7ce5SGreg Kroah-Hartman spin_lock_init(&tty->ctrl_lock); 2990f9e053dcSPeter Hurley spin_lock_init(&tty->flow_lock); 29914a510969SPeter Hurley spin_lock_init(&tty->files_lock); 299296fd7ce5SGreg Kroah-Hartman INIT_LIST_HEAD(&tty->tty_files); 299396fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->SAK_work, do_SAK_work); 299496fd7ce5SGreg Kroah-Hartman 299596fd7ce5SGreg Kroah-Hartman tty->driver = driver; 299696fd7ce5SGreg Kroah-Hartman tty->ops = driver->ops; 299796fd7ce5SGreg Kroah-Hartman tty->index = idx; 299896fd7ce5SGreg Kroah-Hartman tty_line_name(driver, idx, tty->name); 299996fd7ce5SGreg Kroah-Hartman tty->dev = tty_get_device(tty); 30002c964a2fSRasmus Villemoes 30012c964a2fSRasmus Villemoes return tty; 300296fd7ce5SGreg Kroah-Hartman } 300396fd7ce5SGreg Kroah-Hartman 300496fd7ce5SGreg Kroah-Hartman /** 300596fd7ce5SGreg Kroah-Hartman * tty_put_char - write one character to a tty 300696fd7ce5SGreg Kroah-Hartman * @tty: tty 300796fd7ce5SGreg Kroah-Hartman * @ch: character 300896fd7ce5SGreg Kroah-Hartman * 300996fd7ce5SGreg Kroah-Hartman * Write one byte to the tty using the provided put_char method 301096fd7ce5SGreg Kroah-Hartman * if present. Returns the number of characters successfully output. 301196fd7ce5SGreg Kroah-Hartman * 301296fd7ce5SGreg Kroah-Hartman * Note: the specific put_char operation in the driver layer may go 301396fd7ce5SGreg Kroah-Hartman * away soon. Don't call it directly, use this method 301496fd7ce5SGreg Kroah-Hartman */ 301596fd7ce5SGreg Kroah-Hartman 301696fd7ce5SGreg Kroah-Hartman int tty_put_char(struct tty_struct *tty, unsigned char ch) 301796fd7ce5SGreg Kroah-Hartman { 301896fd7ce5SGreg Kroah-Hartman if (tty->ops->put_char) 301996fd7ce5SGreg Kroah-Hartman return tty->ops->put_char(tty, ch); 302096fd7ce5SGreg Kroah-Hartman return tty->ops->write(tty, &ch, 1); 302196fd7ce5SGreg Kroah-Hartman } 302296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_put_char); 302396fd7ce5SGreg Kroah-Hartman 302496fd7ce5SGreg Kroah-Hartman struct class *tty_class; 302596fd7ce5SGreg Kroah-Hartman 30267e73eca6SJiri Slaby static int tty_cdev_add(struct tty_driver *driver, dev_t dev, 30277e73eca6SJiri Slaby unsigned int index, unsigned int count) 30287e73eca6SJiri Slaby { 3029c1a752baSLeon Yu int err; 3030c1a752baSLeon Yu 30317e73eca6SJiri Slaby /* init here, since reused cdevs cause crashes */ 3032a3a10ce3SRichard Watts driver->cdevs[index] = cdev_alloc(); 3033a3a10ce3SRichard Watts if (!driver->cdevs[index]) 3034a3a10ce3SRichard Watts return -ENOMEM; 3035c1a752baSLeon Yu driver->cdevs[index]->ops = &tty_fops; 3036a3a10ce3SRichard Watts driver->cdevs[index]->owner = driver->owner; 3037c1a752baSLeon Yu err = cdev_add(driver->cdevs[index], dev, count); 3038c1a752baSLeon Yu if (err) 3039c1a752baSLeon Yu kobject_put(&driver->cdevs[index]->kobj); 3040c1a752baSLeon Yu return err; 30417e73eca6SJiri Slaby } 30427e73eca6SJiri Slaby 304396fd7ce5SGreg Kroah-Hartman /** 304496fd7ce5SGreg Kroah-Hartman * tty_register_device - register a tty device 304596fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 304696fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 304796fd7ce5SGreg Kroah-Hartman * @device: a struct device that is associated with this tty device. 304896fd7ce5SGreg Kroah-Hartman * This field is optional, if there is no known struct device 304996fd7ce5SGreg Kroah-Hartman * for this tty device it can be set to NULL safely. 305096fd7ce5SGreg Kroah-Hartman * 305196fd7ce5SGreg Kroah-Hartman * Returns a pointer to the struct device for this tty device 305296fd7ce5SGreg Kroah-Hartman * (or ERR_PTR(-EFOO) on error). 305396fd7ce5SGreg Kroah-Hartman * 305496fd7ce5SGreg Kroah-Hartman * This call is required to be made to register an individual tty device 305596fd7ce5SGreg Kroah-Hartman * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 305696fd7ce5SGreg Kroah-Hartman * that bit is not set, this function should not be called by a tty 305796fd7ce5SGreg Kroah-Hartman * driver. 305896fd7ce5SGreg Kroah-Hartman * 305996fd7ce5SGreg Kroah-Hartman * Locking: ?? 306096fd7ce5SGreg Kroah-Hartman */ 306196fd7ce5SGreg Kroah-Hartman 306296fd7ce5SGreg Kroah-Hartman struct device *tty_register_device(struct tty_driver *driver, unsigned index, 306396fd7ce5SGreg Kroah-Hartman struct device *device) 306496fd7ce5SGreg Kroah-Hartman { 30656915c0e4STomas Hlavacek return tty_register_device_attr(driver, index, device, NULL, NULL); 30666915c0e4STomas Hlavacek } 30676915c0e4STomas Hlavacek EXPORT_SYMBOL(tty_register_device); 30686915c0e4STomas Hlavacek 3069b1b79916STomas Hlavacek static void tty_device_create_release(struct device *dev) 3070b1b79916STomas Hlavacek { 307183db1df4SPeter Hurley dev_dbg(dev, "releasing...\n"); 3072b1b79916STomas Hlavacek kfree(dev); 3073b1b79916STomas Hlavacek } 3074b1b79916STomas Hlavacek 30756915c0e4STomas Hlavacek /** 30766915c0e4STomas Hlavacek * tty_register_device_attr - register a tty device 30776915c0e4STomas Hlavacek * @driver: the tty driver that describes the tty device 30786915c0e4STomas Hlavacek * @index: the index in the tty driver for this tty device 30796915c0e4STomas Hlavacek * @device: a struct device that is associated with this tty device. 30806915c0e4STomas Hlavacek * This field is optional, if there is no known struct device 30816915c0e4STomas Hlavacek * for this tty device it can be set to NULL safely. 30826915c0e4STomas Hlavacek * @drvdata: Driver data to be set to device. 30836915c0e4STomas Hlavacek * @attr_grp: Attribute group to be set on device. 30846915c0e4STomas Hlavacek * 30856915c0e4STomas Hlavacek * Returns a pointer to the struct device for this tty device 30866915c0e4STomas Hlavacek * (or ERR_PTR(-EFOO) on error). 30876915c0e4STomas Hlavacek * 30886915c0e4STomas Hlavacek * This call is required to be made to register an individual tty device 30896915c0e4STomas Hlavacek * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 30906915c0e4STomas Hlavacek * that bit is not set, this function should not be called by a tty 30916915c0e4STomas Hlavacek * driver. 30926915c0e4STomas Hlavacek * 30936915c0e4STomas Hlavacek * Locking: ?? 30946915c0e4STomas Hlavacek */ 30956915c0e4STomas Hlavacek struct device *tty_register_device_attr(struct tty_driver *driver, 30966915c0e4STomas Hlavacek unsigned index, struct device *device, 30976915c0e4STomas Hlavacek void *drvdata, 30986915c0e4STomas Hlavacek const struct attribute_group **attr_grp) 30996915c0e4STomas Hlavacek { 310096fd7ce5SGreg Kroah-Hartman char name[64]; 31016915c0e4STomas Hlavacek dev_t devt = MKDEV(driver->major, driver->minor_start) + index; 310293857eddSJohan Hovold struct ktermios *tp; 31036a7e6f78SJohan Hovold struct device *dev; 31046a7e6f78SJohan Hovold int retval; 310596fd7ce5SGreg Kroah-Hartman 310696fd7ce5SGreg Kroah-Hartman if (index >= driver->num) { 3107656fb867SPeter Hurley pr_err("%s: Attempt to register invalid tty line number (%d)\n", 3108656fb867SPeter Hurley driver->name, index); 310996fd7ce5SGreg Kroah-Hartman return ERR_PTR(-EINVAL); 311096fd7ce5SGreg Kroah-Hartman } 311196fd7ce5SGreg Kroah-Hartman 311296fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY) 311396fd7ce5SGreg Kroah-Hartman pty_line_name(driver, index, name); 311496fd7ce5SGreg Kroah-Hartman else 311596fd7ce5SGreg Kroah-Hartman tty_line_name(driver, index, name); 311696fd7ce5SGreg Kroah-Hartman 31176915c0e4STomas Hlavacek dev = kzalloc(sizeof(*dev), GFP_KERNEL); 31186a7e6f78SJohan Hovold if (!dev) 31196a7e6f78SJohan Hovold return ERR_PTR(-ENOMEM); 31206915c0e4STomas Hlavacek 31216915c0e4STomas Hlavacek dev->devt = devt; 31226915c0e4STomas Hlavacek dev->class = tty_class; 31236915c0e4STomas Hlavacek dev->parent = device; 3124b1b79916STomas Hlavacek dev->release = tty_device_create_release; 31256915c0e4STomas Hlavacek dev_set_name(dev, "%s", name); 31266915c0e4STomas Hlavacek dev->groups = attr_grp; 31276915c0e4STomas Hlavacek dev_set_drvdata(dev, drvdata); 31286915c0e4STomas Hlavacek 31296a7e6f78SJohan Hovold dev_set_uevent_suppress(dev, 1); 31306a7e6f78SJohan Hovold 31316915c0e4STomas Hlavacek retval = device_register(dev); 31326915c0e4STomas Hlavacek if (retval) 31336a7e6f78SJohan Hovold goto err_put; 31346a7e6f78SJohan Hovold 31356a7e6f78SJohan Hovold if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 313693857eddSJohan Hovold /* 313793857eddSJohan Hovold * Free any saved termios data so that the termios state is 313893857eddSJohan Hovold * reset when reusing a minor number. 313993857eddSJohan Hovold */ 314093857eddSJohan Hovold tp = driver->termios[index]; 314193857eddSJohan Hovold if (tp) { 314293857eddSJohan Hovold driver->termios[index] = NULL; 314393857eddSJohan Hovold kfree(tp); 314493857eddSJohan Hovold } 314593857eddSJohan Hovold 31466a7e6f78SJohan Hovold retval = tty_cdev_add(driver, devt, index, 1); 31476a7e6f78SJohan Hovold if (retval) 31486a7e6f78SJohan Hovold goto err_del; 31496a7e6f78SJohan Hovold } 31506a7e6f78SJohan Hovold 31516a7e6f78SJohan Hovold dev_set_uevent_suppress(dev, 0); 31526a7e6f78SJohan Hovold kobject_uevent(&dev->kobj, KOBJ_ADD); 31536915c0e4STomas Hlavacek 31546915c0e4STomas Hlavacek return dev; 31556915c0e4STomas Hlavacek 31566a7e6f78SJohan Hovold err_del: 31576a7e6f78SJohan Hovold device_del(dev); 31586a7e6f78SJohan Hovold err_put: 31596915c0e4STomas Hlavacek put_device(dev); 31606a7e6f78SJohan Hovold 31616915c0e4STomas Hlavacek return ERR_PTR(retval); 31626915c0e4STomas Hlavacek } 31636915c0e4STomas Hlavacek EXPORT_SYMBOL_GPL(tty_register_device_attr); 316496fd7ce5SGreg Kroah-Hartman 316596fd7ce5SGreg Kroah-Hartman /** 316696fd7ce5SGreg Kroah-Hartman * tty_unregister_device - unregister a tty device 316796fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 316896fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 316996fd7ce5SGreg Kroah-Hartman * 317096fd7ce5SGreg Kroah-Hartman * If a tty device is registered with a call to tty_register_device() then 317196fd7ce5SGreg Kroah-Hartman * this function must be called when the tty device is gone. 317296fd7ce5SGreg Kroah-Hartman * 317396fd7ce5SGreg Kroah-Hartman * Locking: ?? 317496fd7ce5SGreg Kroah-Hartman */ 317596fd7ce5SGreg Kroah-Hartman 317696fd7ce5SGreg Kroah-Hartman void tty_unregister_device(struct tty_driver *driver, unsigned index) 317796fd7ce5SGreg Kroah-Hartman { 317896fd7ce5SGreg Kroah-Hartman device_destroy(tty_class, 317996fd7ce5SGreg Kroah-Hartman MKDEV(driver->major, driver->minor_start) + index); 3180a3a10ce3SRichard Watts if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 3181a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3182a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3183a3a10ce3SRichard Watts } 318496fd7ce5SGreg Kroah-Hartman } 318596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_device); 318696fd7ce5SGreg Kroah-Hartman 31877f0bc6a6SJiri Slaby /** 31887f0bc6a6SJiri Slaby * __tty_alloc_driver -- allocate tty driver 31897f0bc6a6SJiri Slaby * @lines: count of lines this driver can handle at most 319087838ae3SThadeu Lima de Souza Cascardo * @owner: module which is responsible for this driver 31917f0bc6a6SJiri Slaby * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags 31927f0bc6a6SJiri Slaby * 31937f0bc6a6SJiri Slaby * This should not be called directly, some of the provided macros should be 31947f0bc6a6SJiri Slaby * used instead. Use IS_ERR and friends on @retval. 31957f0bc6a6SJiri Slaby */ 31967f0bc6a6SJiri Slaby struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner, 31977f0bc6a6SJiri Slaby unsigned long flags) 319896fd7ce5SGreg Kroah-Hartman { 319996fd7ce5SGreg Kroah-Hartman struct tty_driver *driver; 32007e73eca6SJiri Slaby unsigned int cdevs = 1; 320116a02081SJiri Slaby int err; 320296fd7ce5SGreg Kroah-Hartman 32030019b408SJiri Slaby if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1)) 32047f0bc6a6SJiri Slaby return ERR_PTR(-EINVAL); 32057f0bc6a6SJiri Slaby 320696fd7ce5SGreg Kroah-Hartman driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); 32077f0bc6a6SJiri Slaby if (!driver) 32087f0bc6a6SJiri Slaby return ERR_PTR(-ENOMEM); 32097f0bc6a6SJiri Slaby 321096fd7ce5SGreg Kroah-Hartman kref_init(&driver->kref); 321196fd7ce5SGreg Kroah-Hartman driver->magic = TTY_DRIVER_MAGIC; 321296fd7ce5SGreg Kroah-Hartman driver->num = lines; 32131a54a76dSJiri Slaby driver->owner = owner; 32147f0bc6a6SJiri Slaby driver->flags = flags; 321516a02081SJiri Slaby 321616a02081SJiri Slaby if (!(flags & TTY_DRIVER_DEVPTS_MEM)) { 321716a02081SJiri Slaby driver->ttys = kcalloc(lines, sizeof(*driver->ttys), 321816a02081SJiri Slaby GFP_KERNEL); 321916a02081SJiri Slaby driver->termios = kcalloc(lines, sizeof(*driver->termios), 322016a02081SJiri Slaby GFP_KERNEL); 322116a02081SJiri Slaby if (!driver->ttys || !driver->termios) { 322216a02081SJiri Slaby err = -ENOMEM; 322316a02081SJiri Slaby goto err_free_all; 322416a02081SJiri Slaby } 322516a02081SJiri Slaby } 322616a02081SJiri Slaby 322716a02081SJiri Slaby if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 322816a02081SJiri Slaby driver->ports = kcalloc(lines, sizeof(*driver->ports), 322916a02081SJiri Slaby GFP_KERNEL); 323016a02081SJiri Slaby if (!driver->ports) { 323116a02081SJiri Slaby err = -ENOMEM; 323216a02081SJiri Slaby goto err_free_all; 323316a02081SJiri Slaby } 32347e73eca6SJiri Slaby cdevs = lines; 32357e73eca6SJiri Slaby } 32367e73eca6SJiri Slaby 32377e73eca6SJiri Slaby driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL); 32387e73eca6SJiri Slaby if (!driver->cdevs) { 32397e73eca6SJiri Slaby err = -ENOMEM; 32407e73eca6SJiri Slaby goto err_free_all; 324116a02081SJiri Slaby } 32427f0bc6a6SJiri Slaby 324396fd7ce5SGreg Kroah-Hartman return driver; 324416a02081SJiri Slaby err_free_all: 324516a02081SJiri Slaby kfree(driver->ports); 324616a02081SJiri Slaby kfree(driver->ttys); 324716a02081SJiri Slaby kfree(driver->termios); 3248a3a10ce3SRichard Watts kfree(driver->cdevs); 324916a02081SJiri Slaby kfree(driver); 325016a02081SJiri Slaby return ERR_PTR(err); 325196fd7ce5SGreg Kroah-Hartman } 32527f0bc6a6SJiri Slaby EXPORT_SYMBOL(__tty_alloc_driver); 325396fd7ce5SGreg Kroah-Hartman 325496fd7ce5SGreg Kroah-Hartman static void destruct_tty_driver(struct kref *kref) 325596fd7ce5SGreg Kroah-Hartman { 325696fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = container_of(kref, struct tty_driver, kref); 325796fd7ce5SGreg Kroah-Hartman int i; 325896fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 325996fd7ce5SGreg Kroah-Hartman 326096fd7ce5SGreg Kroah-Hartman if (driver->flags & TTY_DRIVER_INSTALLED) { 326196fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 326296fd7ce5SGreg Kroah-Hartman tp = driver->termios[i]; 326396fd7ce5SGreg Kroah-Hartman if (tp) { 326496fd7ce5SGreg Kroah-Hartman driver->termios[i] = NULL; 326596fd7ce5SGreg Kroah-Hartman kfree(tp); 326696fd7ce5SGreg Kroah-Hartman } 326796fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) 326896fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 326996fd7ce5SGreg Kroah-Hartman } 327096fd7ce5SGreg Kroah-Hartman proc_tty_unregister_driver(driver); 32717e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) 3272a3a10ce3SRichard Watts cdev_del(driver->cdevs[0]); 327396fd7ce5SGreg Kroah-Hartman } 32747e73eca6SJiri Slaby kfree(driver->cdevs); 327504831dc1SJiri Slaby kfree(driver->ports); 327616a02081SJiri Slaby kfree(driver->termios); 327716a02081SJiri Slaby kfree(driver->ttys); 327896fd7ce5SGreg Kroah-Hartman kfree(driver); 327996fd7ce5SGreg Kroah-Hartman } 328096fd7ce5SGreg Kroah-Hartman 328196fd7ce5SGreg Kroah-Hartman void tty_driver_kref_put(struct tty_driver *driver) 328296fd7ce5SGreg Kroah-Hartman { 328396fd7ce5SGreg Kroah-Hartman kref_put(&driver->kref, destruct_tty_driver); 328496fd7ce5SGreg Kroah-Hartman } 328596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_driver_kref_put); 328696fd7ce5SGreg Kroah-Hartman 328796fd7ce5SGreg Kroah-Hartman void tty_set_operations(struct tty_driver *driver, 328896fd7ce5SGreg Kroah-Hartman const struct tty_operations *op) 328996fd7ce5SGreg Kroah-Hartman { 329096fd7ce5SGreg Kroah-Hartman driver->ops = op; 329196fd7ce5SGreg Kroah-Hartman }; 329296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_set_operations); 329396fd7ce5SGreg Kroah-Hartman 329496fd7ce5SGreg Kroah-Hartman void put_tty_driver(struct tty_driver *d) 329596fd7ce5SGreg Kroah-Hartman { 329696fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(d); 329796fd7ce5SGreg Kroah-Hartman } 329896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(put_tty_driver); 329996fd7ce5SGreg Kroah-Hartman 330096fd7ce5SGreg Kroah-Hartman /* 330196fd7ce5SGreg Kroah-Hartman * Called by a tty driver to register itself. 330296fd7ce5SGreg Kroah-Hartman */ 330396fd7ce5SGreg Kroah-Hartman int tty_register_driver(struct tty_driver *driver) 330496fd7ce5SGreg Kroah-Hartman { 330596fd7ce5SGreg Kroah-Hartman int error; 330696fd7ce5SGreg Kroah-Hartman int i; 330796fd7ce5SGreg Kroah-Hartman dev_t dev; 330896fd7ce5SGreg Kroah-Hartman struct device *d; 330996fd7ce5SGreg Kroah-Hartman 331096fd7ce5SGreg Kroah-Hartman if (!driver->major) { 331196fd7ce5SGreg Kroah-Hartman error = alloc_chrdev_region(&dev, driver->minor_start, 331296fd7ce5SGreg Kroah-Hartman driver->num, driver->name); 331396fd7ce5SGreg Kroah-Hartman if (!error) { 331496fd7ce5SGreg Kroah-Hartman driver->major = MAJOR(dev); 331596fd7ce5SGreg Kroah-Hartman driver->minor_start = MINOR(dev); 331696fd7ce5SGreg Kroah-Hartman } 331796fd7ce5SGreg Kroah-Hartman } else { 331896fd7ce5SGreg Kroah-Hartman dev = MKDEV(driver->major, driver->minor_start); 331996fd7ce5SGreg Kroah-Hartman error = register_chrdev_region(dev, driver->num, driver->name); 332096fd7ce5SGreg Kroah-Hartman } 33219bb8a3d4SJiri Slaby if (error < 0) 332216a02081SJiri Slaby goto err; 332396fd7ce5SGreg Kroah-Hartman 33247e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) { 33257e73eca6SJiri Slaby error = tty_cdev_add(driver, dev, 0, driver->num); 33269bb8a3d4SJiri Slaby if (error) 33279bb8a3d4SJiri Slaby goto err_unreg_char; 33287e73eca6SJiri Slaby } 332996fd7ce5SGreg Kroah-Hartman 333096fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 333196fd7ce5SGreg Kroah-Hartman list_add(&driver->tty_drivers, &tty_drivers); 333296fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 333396fd7ce5SGreg Kroah-Hartman 333496fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { 333596fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 333696fd7ce5SGreg Kroah-Hartman d = tty_register_device(driver, i, NULL); 333796fd7ce5SGreg Kroah-Hartman if (IS_ERR(d)) { 333896fd7ce5SGreg Kroah-Hartman error = PTR_ERR(d); 333916a02081SJiri Slaby goto err_unreg_devs; 334096fd7ce5SGreg Kroah-Hartman } 334196fd7ce5SGreg Kroah-Hartman } 334296fd7ce5SGreg Kroah-Hartman } 334396fd7ce5SGreg Kroah-Hartman proc_tty_register_driver(driver); 334496fd7ce5SGreg Kroah-Hartman driver->flags |= TTY_DRIVER_INSTALLED; 334596fd7ce5SGreg Kroah-Hartman return 0; 334696fd7ce5SGreg Kroah-Hartman 334716a02081SJiri Slaby err_unreg_devs: 334896fd7ce5SGreg Kroah-Hartman for (i--; i >= 0; i--) 334996fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 335096fd7ce5SGreg Kroah-Hartman 335196fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 335296fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 335396fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 335496fd7ce5SGreg Kroah-Hartman 33559bb8a3d4SJiri Slaby err_unreg_char: 335696fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(dev, driver->num); 335716a02081SJiri Slaby err: 335896fd7ce5SGreg Kroah-Hartman return error; 335996fd7ce5SGreg Kroah-Hartman } 336096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_register_driver); 336196fd7ce5SGreg Kroah-Hartman 336296fd7ce5SGreg Kroah-Hartman /* 336396fd7ce5SGreg Kroah-Hartman * Called by a tty driver to unregister itself. 336496fd7ce5SGreg Kroah-Hartman */ 336596fd7ce5SGreg Kroah-Hartman int tty_unregister_driver(struct tty_driver *driver) 336696fd7ce5SGreg Kroah-Hartman { 336796fd7ce5SGreg Kroah-Hartman #if 0 336896fd7ce5SGreg Kroah-Hartman /* FIXME */ 336996fd7ce5SGreg Kroah-Hartman if (driver->refcount) 337096fd7ce5SGreg Kroah-Hartman return -EBUSY; 337196fd7ce5SGreg Kroah-Hartman #endif 337296fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), 337396fd7ce5SGreg Kroah-Hartman driver->num); 337496fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 337596fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 337696fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 337796fd7ce5SGreg Kroah-Hartman return 0; 337896fd7ce5SGreg Kroah-Hartman } 337996fd7ce5SGreg Kroah-Hartman 338096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_driver); 338196fd7ce5SGreg Kroah-Hartman 338296fd7ce5SGreg Kroah-Hartman dev_t tty_devnum(struct tty_struct *tty) 338396fd7ce5SGreg Kroah-Hartman { 338496fd7ce5SGreg Kroah-Hartman return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; 338596fd7ce5SGreg Kroah-Hartman } 338696fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_devnum); 338796fd7ce5SGreg Kroah-Hartman 338896fd7ce5SGreg Kroah-Hartman void tty_default_fops(struct file_operations *fops) 338996fd7ce5SGreg Kroah-Hartman { 339096fd7ce5SGreg Kroah-Hartman *fops = tty_fops; 339196fd7ce5SGreg Kroah-Hartman } 339296fd7ce5SGreg Kroah-Hartman 33932c9ede55SAl Viro static char *tty_devnode(struct device *dev, umode_t *mode) 339496fd7ce5SGreg Kroah-Hartman { 339596fd7ce5SGreg Kroah-Hartman if (!mode) 339696fd7ce5SGreg Kroah-Hartman return NULL; 339796fd7ce5SGreg Kroah-Hartman if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || 339896fd7ce5SGreg Kroah-Hartman dev->devt == MKDEV(TTYAUX_MAJOR, 2)) 339996fd7ce5SGreg Kroah-Hartman *mode = 0666; 340096fd7ce5SGreg Kroah-Hartman return NULL; 340196fd7ce5SGreg Kroah-Hartman } 340296fd7ce5SGreg Kroah-Hartman 340396fd7ce5SGreg Kroah-Hartman static int __init tty_class_init(void) 340496fd7ce5SGreg Kroah-Hartman { 340596fd7ce5SGreg Kroah-Hartman tty_class = class_create(THIS_MODULE, "tty"); 340696fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty_class)) 340796fd7ce5SGreg Kroah-Hartman return PTR_ERR(tty_class); 340896fd7ce5SGreg Kroah-Hartman tty_class->devnode = tty_devnode; 340996fd7ce5SGreg Kroah-Hartman return 0; 341096fd7ce5SGreg Kroah-Hartman } 341196fd7ce5SGreg Kroah-Hartman 341296fd7ce5SGreg Kroah-Hartman postcore_initcall(tty_class_init); 341396fd7ce5SGreg Kroah-Hartman 341496fd7ce5SGreg Kroah-Hartman /* 3/2004 jmc: why do these devices exist? */ 341596fd7ce5SGreg Kroah-Hartman static struct cdev tty_cdev, console_cdev; 341696fd7ce5SGreg Kroah-Hartman 3417fbc92a34SKay Sievers static ssize_t show_cons_active(struct device *dev, 3418fbc92a34SKay Sievers struct device_attribute *attr, char *buf) 3419fbc92a34SKay Sievers { 3420fbc92a34SKay Sievers struct console *cs[16]; 3421fbc92a34SKay Sievers int i = 0; 3422fbc92a34SKay Sievers struct console *c; 3423fbc92a34SKay Sievers ssize_t count = 0; 3424fbc92a34SKay Sievers 3425ac751efaSTorben Hohn console_lock(); 3426a2a6a822SKay Sievers for_each_console(c) { 3427fbc92a34SKay Sievers if (!c->device) 3428fbc92a34SKay Sievers continue; 3429fbc92a34SKay Sievers if (!c->write) 3430fbc92a34SKay Sievers continue; 3431fbc92a34SKay Sievers if ((c->flags & CON_ENABLED) == 0) 3432fbc92a34SKay Sievers continue; 3433fbc92a34SKay Sievers cs[i++] = c; 3434fbc92a34SKay Sievers if (i >= ARRAY_SIZE(cs)) 3435fbc92a34SKay Sievers break; 3436fbc92a34SKay Sievers } 3437723abd87SHannes Reinecke while (i--) { 3438723abd87SHannes Reinecke int index = cs[i]->index; 3439723abd87SHannes Reinecke struct tty_driver *drv = cs[i]->device(cs[i], &index); 3440723abd87SHannes Reinecke 3441723abd87SHannes Reinecke /* don't resolve tty0 as some programs depend on it */ 3442723abd87SHannes Reinecke if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR)) 3443723abd87SHannes Reinecke count += tty_line_name(drv, index, buf + count); 3444723abd87SHannes Reinecke else 3445723abd87SHannes Reinecke count += sprintf(buf + count, "%s%d", 3446723abd87SHannes Reinecke cs[i]->name, cs[i]->index); 3447723abd87SHannes Reinecke 3448723abd87SHannes Reinecke count += sprintf(buf + count, "%c", i ? ' ':'\n'); 3449723abd87SHannes Reinecke } 3450ac751efaSTorben Hohn console_unlock(); 3451fbc92a34SKay Sievers 3452fbc92a34SKay Sievers return count; 3453fbc92a34SKay Sievers } 3454fbc92a34SKay Sievers static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL); 3455fbc92a34SKay Sievers 34561083a7beSTakashi Iwai static struct attribute *cons_dev_attrs[] = { 34571083a7beSTakashi Iwai &dev_attr_active.attr, 34581083a7beSTakashi Iwai NULL 34591083a7beSTakashi Iwai }; 34601083a7beSTakashi Iwai 34611083a7beSTakashi Iwai ATTRIBUTE_GROUPS(cons_dev); 34621083a7beSTakashi Iwai 3463fbc92a34SKay Sievers static struct device *consdev; 3464fbc92a34SKay Sievers 3465fbc92a34SKay Sievers void console_sysfs_notify(void) 3466fbc92a34SKay Sievers { 3467fbc92a34SKay Sievers if (consdev) 3468fbc92a34SKay Sievers sysfs_notify(&consdev->kobj, NULL, "active"); 3469fbc92a34SKay Sievers } 3470fbc92a34SKay Sievers 347196fd7ce5SGreg Kroah-Hartman /* 347296fd7ce5SGreg Kroah-Hartman * Ok, now we can initialize the rest of the tty devices and can count 347396fd7ce5SGreg Kroah-Hartman * on memory allocations, interrupts etc.. 347496fd7ce5SGreg Kroah-Hartman */ 347596fd7ce5SGreg Kroah-Hartman int __init tty_init(void) 347696fd7ce5SGreg Kroah-Hartman { 347796fd7ce5SGreg Kroah-Hartman cdev_init(&tty_cdev, &tty_fops); 347896fd7ce5SGreg Kroah-Hartman if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || 347996fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) 348096fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/tty driver\n"); 3481fbc92a34SKay Sievers device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty"); 348296fd7ce5SGreg Kroah-Hartman 348396fd7ce5SGreg Kroah-Hartman cdev_init(&console_cdev, &console_fops); 348496fd7ce5SGreg Kroah-Hartman if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || 348596fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) 348696fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/console driver\n"); 34871083a7beSTakashi Iwai consdev = device_create_with_groups(tty_class, NULL, 34881083a7beSTakashi Iwai MKDEV(TTYAUX_MAJOR, 1), NULL, 34891083a7beSTakashi Iwai cons_dev_groups, "console"); 3490fbc92a34SKay Sievers if (IS_ERR(consdev)) 3491fbc92a34SKay Sievers consdev = NULL; 349296fd7ce5SGreg Kroah-Hartman 349396fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_VT 349496fd7ce5SGreg Kroah-Hartman vty_init(&console_fops); 349596fd7ce5SGreg Kroah-Hartman #endif 349696fd7ce5SGreg Kroah-Hartman return 0; 349796fd7ce5SGreg Kroah-Hartman } 349896fd7ce5SGreg Kroah-Hartman 3499