196fd7ce5SGreg Kroah-Hartman /* 296fd7ce5SGreg Kroah-Hartman * Copyright (C) 1991, 1992 Linus Torvalds 396fd7ce5SGreg Kroah-Hartman */ 496fd7ce5SGreg Kroah-Hartman 596fd7ce5SGreg Kroah-Hartman /* 696fd7ce5SGreg Kroah-Hartman * 'tty_io.c' gives an orthogonal feeling to tty's, be they consoles 796fd7ce5SGreg Kroah-Hartman * or rs-channels. It also implements echoing, cooked mode etc. 896fd7ce5SGreg Kroah-Hartman * 996fd7ce5SGreg Kroah-Hartman * Kill-line thanks to John T Kohl, who also corrected VMIN = VTIME = 0. 1096fd7ce5SGreg Kroah-Hartman * 1196fd7ce5SGreg Kroah-Hartman * Modified by Theodore Ts'o, 9/14/92, to dynamically allocate the 1296fd7ce5SGreg Kroah-Hartman * tty_struct and tty_queue structures. Previously there was an array 1396fd7ce5SGreg Kroah-Hartman * of 256 tty_struct's which was statically allocated, and the 1496fd7ce5SGreg Kroah-Hartman * tty_queue structures were allocated at boot time. Both are now 1596fd7ce5SGreg Kroah-Hartman * dynamically allocated only when the tty is open. 1696fd7ce5SGreg Kroah-Hartman * 1796fd7ce5SGreg Kroah-Hartman * Also restructured routines so that there is more of a separation 1896fd7ce5SGreg Kroah-Hartman * between the high-level tty routines (tty_io.c and tty_ioctl.c) and 1996fd7ce5SGreg Kroah-Hartman * the low-level tty routines (serial.c, pty.c, console.c). This 2096fd7ce5SGreg Kroah-Hartman * makes for cleaner and more compact code. -TYT, 9/17/92 2196fd7ce5SGreg Kroah-Hartman * 2296fd7ce5SGreg Kroah-Hartman * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines 2396fd7ce5SGreg Kroah-Hartman * which can be dynamically activated and de-activated by the line 2496fd7ce5SGreg Kroah-Hartman * discipline handling modules (like SLIP). 2596fd7ce5SGreg Kroah-Hartman * 2696fd7ce5SGreg Kroah-Hartman * NOTE: pay no attention to the line discipline code (yet); its 2796fd7ce5SGreg Kroah-Hartman * interface is still subject to change in this version... 2896fd7ce5SGreg Kroah-Hartman * -- TYT, 1/31/92 2996fd7ce5SGreg Kroah-Hartman * 3096fd7ce5SGreg Kroah-Hartman * Added functionality to the OPOST tty handling. No delays, but all 3196fd7ce5SGreg Kroah-Hartman * other bits should be there. 3296fd7ce5SGreg Kroah-Hartman * -- Nick Holloway <alfie@dcs.warwick.ac.uk>, 27th May 1993. 3396fd7ce5SGreg Kroah-Hartman * 3496fd7ce5SGreg Kroah-Hartman * Rewrote canonical mode and added more termios flags. 3596fd7ce5SGreg Kroah-Hartman * -- julian@uhunix.uhcc.hawaii.edu (J. Cowley), 13Jan94 3696fd7ce5SGreg Kroah-Hartman * 3796fd7ce5SGreg Kroah-Hartman * Reorganized FASYNC support so mouse code can share it. 3896fd7ce5SGreg Kroah-Hartman * -- ctm@ardi.com, 9Sep95 3996fd7ce5SGreg Kroah-Hartman * 4096fd7ce5SGreg Kroah-Hartman * New TIOCLINUX variants added. 4196fd7ce5SGreg Kroah-Hartman * -- mj@k332.feld.cvut.cz, 19-Nov-95 4296fd7ce5SGreg Kroah-Hartman * 4396fd7ce5SGreg Kroah-Hartman * Restrict vt switching via ioctl() 4496fd7ce5SGreg Kroah-Hartman * -- grif@cs.ucr.edu, 5-Dec-95 4596fd7ce5SGreg Kroah-Hartman * 4696fd7ce5SGreg Kroah-Hartman * Move console and virtual terminal code to more appropriate files, 4796fd7ce5SGreg Kroah-Hartman * implement CONFIG_VT and generalize console device interface. 4896fd7ce5SGreg Kroah-Hartman * -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97 4996fd7ce5SGreg Kroah-Hartman * 5096fd7ce5SGreg Kroah-Hartman * Rewrote tty_init_dev and tty_release_dev to eliminate races. 5196fd7ce5SGreg Kroah-Hartman * -- Bill Hawes <whawes@star.net>, June 97 5296fd7ce5SGreg Kroah-Hartman * 5396fd7ce5SGreg Kroah-Hartman * Added devfs support. 5496fd7ce5SGreg Kroah-Hartman * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 13-Jan-1998 5596fd7ce5SGreg Kroah-Hartman * 5696fd7ce5SGreg Kroah-Hartman * Added support for a Unix98-style ptmx device. 5796fd7ce5SGreg Kroah-Hartman * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 5896fd7ce5SGreg Kroah-Hartman * 5996fd7ce5SGreg Kroah-Hartman * Reduced memory usage for older ARM systems 6096fd7ce5SGreg Kroah-Hartman * -- Russell King <rmk@arm.linux.org.uk> 6196fd7ce5SGreg Kroah-Hartman * 6296fd7ce5SGreg Kroah-Hartman * Move do_SAK() into process context. Less stack use in devfs functions. 6396fd7ce5SGreg Kroah-Hartman * alloc_tty_struct() always uses kmalloc() 6496fd7ce5SGreg Kroah-Hartman * -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01 6596fd7ce5SGreg Kroah-Hartman */ 6696fd7ce5SGreg Kroah-Hartman 6796fd7ce5SGreg Kroah-Hartman #include <linux/types.h> 6896fd7ce5SGreg Kroah-Hartman #include <linux/major.h> 6996fd7ce5SGreg Kroah-Hartman #include <linux/errno.h> 7096fd7ce5SGreg Kroah-Hartman #include <linux/signal.h> 7196fd7ce5SGreg Kroah-Hartman #include <linux/fcntl.h> 7296fd7ce5SGreg Kroah-Hartman #include <linux/sched.h> 7396fd7ce5SGreg Kroah-Hartman #include <linux/interrupt.h> 7496fd7ce5SGreg Kroah-Hartman #include <linux/tty.h> 7596fd7ce5SGreg Kroah-Hartman #include <linux/tty_driver.h> 7696fd7ce5SGreg Kroah-Hartman #include <linux/tty_flip.h> 7796fd7ce5SGreg Kroah-Hartman #include <linux/devpts_fs.h> 7896fd7ce5SGreg Kroah-Hartman #include <linux/file.h> 7996fd7ce5SGreg Kroah-Hartman #include <linux/fdtable.h> 8096fd7ce5SGreg Kroah-Hartman #include <linux/console.h> 8196fd7ce5SGreg Kroah-Hartman #include <linux/timer.h> 8296fd7ce5SGreg Kroah-Hartman #include <linux/ctype.h> 8396fd7ce5SGreg Kroah-Hartman #include <linux/kd.h> 8496fd7ce5SGreg Kroah-Hartman #include <linux/mm.h> 8596fd7ce5SGreg Kroah-Hartman #include <linux/string.h> 8696fd7ce5SGreg Kroah-Hartman #include <linux/slab.h> 8796fd7ce5SGreg Kroah-Hartman #include <linux/poll.h> 8896fd7ce5SGreg Kroah-Hartman #include <linux/proc_fs.h> 8996fd7ce5SGreg Kroah-Hartman #include <linux/init.h> 9096fd7ce5SGreg Kroah-Hartman #include <linux/module.h> 9196fd7ce5SGreg Kroah-Hartman #include <linux/device.h> 9296fd7ce5SGreg Kroah-Hartman #include <linux/wait.h> 9396fd7ce5SGreg Kroah-Hartman #include <linux/bitops.h> 9496fd7ce5SGreg Kroah-Hartman #include <linux/delay.h> 9596fd7ce5SGreg Kroah-Hartman #include <linux/seq_file.h> 9696fd7ce5SGreg Kroah-Hartman #include <linux/serial.h> 975a3c6b25SManuel Zerpies #include <linux/ratelimit.h> 9896fd7ce5SGreg Kroah-Hartman 9996fd7ce5SGreg Kroah-Hartman #include <linux/uaccess.h> 10096fd7ce5SGreg Kroah-Hartman 10196fd7ce5SGreg Kroah-Hartman #include <linux/kbd_kern.h> 10296fd7ce5SGreg Kroah-Hartman #include <linux/vt_kern.h> 10396fd7ce5SGreg Kroah-Hartman #include <linux/selection.h> 10496fd7ce5SGreg Kroah-Hartman 10596fd7ce5SGreg Kroah-Hartman #include <linux/kmod.h> 10696fd7ce5SGreg Kroah-Hartman #include <linux/nsproxy.h> 10796fd7ce5SGreg Kroah-Hartman 10896fd7ce5SGreg Kroah-Hartman #undef TTY_DEBUG_HANGUP 109accff793SPeter Hurley #ifdef TTY_DEBUG_HANGUP 110accff793SPeter Hurley # define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args) 111accff793SPeter Hurley #else 112accff793SPeter Hurley # define tty_debug_hangup(tty, f, args...) do { } while (0) 113accff793SPeter Hurley #endif 11496fd7ce5SGreg Kroah-Hartman 11596fd7ce5SGreg Kroah-Hartman #define TTY_PARANOIA_CHECK 1 11696fd7ce5SGreg Kroah-Hartman #define CHECK_TTY_COUNT 1 11796fd7ce5SGreg Kroah-Hartman 11896fd7ce5SGreg Kroah-Hartman struct ktermios tty_std_termios = { /* for the benefit of tty drivers */ 11996fd7ce5SGreg Kroah-Hartman .c_iflag = ICRNL | IXON, 12096fd7ce5SGreg Kroah-Hartman .c_oflag = OPOST | ONLCR, 12196fd7ce5SGreg Kroah-Hartman .c_cflag = B38400 | CS8 | CREAD | HUPCL, 12296fd7ce5SGreg Kroah-Hartman .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | 12396fd7ce5SGreg Kroah-Hartman ECHOCTL | ECHOKE | IEXTEN, 12496fd7ce5SGreg Kroah-Hartman .c_cc = INIT_C_CC, 12596fd7ce5SGreg Kroah-Hartman .c_ispeed = 38400, 126133b1306SPeter Hurley .c_ospeed = 38400, 127133b1306SPeter Hurley /* .c_line = N_TTY, */ 12896fd7ce5SGreg Kroah-Hartman }; 12996fd7ce5SGreg Kroah-Hartman 13096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_std_termios); 13196fd7ce5SGreg Kroah-Hartman 13296fd7ce5SGreg Kroah-Hartman /* This list gets poked at by procfs and various bits of boot up code. This 13396fd7ce5SGreg Kroah-Hartman could do with some rationalisation such as pulling the tty proc function 13496fd7ce5SGreg Kroah-Hartman into this file */ 13596fd7ce5SGreg Kroah-Hartman 13696fd7ce5SGreg Kroah-Hartman LIST_HEAD(tty_drivers); /* linked list of tty drivers */ 13796fd7ce5SGreg Kroah-Hartman 138d1d027efSPeter Hurley /* Mutex to protect creating and releasing a tty */ 13996fd7ce5SGreg Kroah-Hartman DEFINE_MUTEX(tty_mutex); 14096fd7ce5SGreg Kroah-Hartman 14196fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); 14296fd7ce5SGreg Kroah-Hartman static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *); 14396fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *, const char __user *, 14496fd7ce5SGreg Kroah-Hartman size_t, loff_t *); 14596fd7ce5SGreg Kroah-Hartman static unsigned int tty_poll(struct file *, poll_table *); 14696fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *, struct file *); 14796fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 14896fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 14996fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 15096fd7ce5SGreg Kroah-Hartman unsigned long arg); 15196fd7ce5SGreg Kroah-Hartman #else 15296fd7ce5SGreg Kroah-Hartman #define tty_compat_ioctl NULL 15396fd7ce5SGreg Kroah-Hartman #endif 15496fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on); 15596fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on); 15696fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx); 15796fd7ce5SGreg Kroah-Hartman 15896fd7ce5SGreg Kroah-Hartman /** 15996fd7ce5SGreg Kroah-Hartman * free_tty_struct - free a disused tty 16096fd7ce5SGreg Kroah-Hartman * @tty: tty struct to free 16196fd7ce5SGreg Kroah-Hartman * 16296fd7ce5SGreg Kroah-Hartman * Free the write buffers, tty queue and tty memory itself. 16396fd7ce5SGreg Kroah-Hartman * 16496fd7ce5SGreg Kroah-Hartman * Locking: none. Must be called after tty is definitely unused 16596fd7ce5SGreg Kroah-Hartman */ 16696fd7ce5SGreg Kroah-Hartman 167a3123fd0SPeter Hurley static void free_tty_struct(struct tty_struct *tty) 16896fd7ce5SGreg Kroah-Hartman { 169c8b710b3SPeter Hurley tty_ldisc_deinit(tty); 17096fd7ce5SGreg Kroah-Hartman put_device(tty->dev); 17196fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 17289c8d91eSAlan Cox tty->magic = 0xDEADDEAD; 17396fd7ce5SGreg Kroah-Hartman kfree(tty); 17496fd7ce5SGreg Kroah-Hartman } 17596fd7ce5SGreg Kroah-Hartman 17696fd7ce5SGreg Kroah-Hartman static inline struct tty_struct *file_tty(struct file *file) 17796fd7ce5SGreg Kroah-Hartman { 17896fd7ce5SGreg Kroah-Hartman return ((struct tty_file_private *)file->private_data)->tty; 17996fd7ce5SGreg Kroah-Hartman } 18096fd7ce5SGreg Kroah-Hartman 181fa90e1c9SJiri Slaby int tty_alloc_file(struct file *file) 18296fd7ce5SGreg Kroah-Hartman { 18396fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 18496fd7ce5SGreg Kroah-Hartman 18596fd7ce5SGreg Kroah-Hartman priv = kmalloc(sizeof(*priv), GFP_KERNEL); 18696fd7ce5SGreg Kroah-Hartman if (!priv) 18796fd7ce5SGreg Kroah-Hartman return -ENOMEM; 18896fd7ce5SGreg Kroah-Hartman 189fa90e1c9SJiri Slaby file->private_data = priv; 190fa90e1c9SJiri Slaby 191fa90e1c9SJiri Slaby return 0; 192fa90e1c9SJiri Slaby } 193fa90e1c9SJiri Slaby 194fa90e1c9SJiri Slaby /* Associate a new file with the tty structure */ 195fa90e1c9SJiri Slaby void tty_add_file(struct tty_struct *tty, struct file *file) 196fa90e1c9SJiri Slaby { 197fa90e1c9SJiri Slaby struct tty_file_private *priv = file->private_data; 198fa90e1c9SJiri Slaby 19996fd7ce5SGreg Kroah-Hartman priv->tty = tty; 20096fd7ce5SGreg Kroah-Hartman priv->file = file; 20196fd7ce5SGreg Kroah-Hartman 2024a510969SPeter Hurley spin_lock(&tty->files_lock); 20396fd7ce5SGreg Kroah-Hartman list_add(&priv->list, &tty->tty_files); 2044a510969SPeter Hurley spin_unlock(&tty->files_lock); 205fa90e1c9SJiri Slaby } 20696fd7ce5SGreg Kroah-Hartman 207fa90e1c9SJiri Slaby /** 208fa90e1c9SJiri Slaby * tty_free_file - free file->private_data 209fa90e1c9SJiri Slaby * 210fa90e1c9SJiri Slaby * This shall be used only for fail path handling when tty_add_file was not 211fa90e1c9SJiri Slaby * called yet. 212fa90e1c9SJiri Slaby */ 213fa90e1c9SJiri Slaby void tty_free_file(struct file *file) 214fa90e1c9SJiri Slaby { 215fa90e1c9SJiri Slaby struct tty_file_private *priv = file->private_data; 216fa90e1c9SJiri Slaby 217fa90e1c9SJiri Slaby file->private_data = NULL; 218fa90e1c9SJiri Slaby kfree(priv); 21996fd7ce5SGreg Kroah-Hartman } 22096fd7ce5SGreg Kroah-Hartman 22196fd7ce5SGreg Kroah-Hartman /* Delete file from its tty */ 2222520e274SJosh Triplett static void tty_del_file(struct file *file) 22396fd7ce5SGreg Kroah-Hartman { 22496fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv = file->private_data; 2254a510969SPeter Hurley struct tty_struct *tty = priv->tty; 22696fd7ce5SGreg Kroah-Hartman 2274a510969SPeter Hurley spin_lock(&tty->files_lock); 22896fd7ce5SGreg Kroah-Hartman list_del(&priv->list); 2294a510969SPeter Hurley spin_unlock(&tty->files_lock); 230fa90e1c9SJiri Slaby tty_free_file(file); 23196fd7ce5SGreg Kroah-Hartman } 23296fd7ce5SGreg Kroah-Hartman 23396fd7ce5SGreg Kroah-Hartman 23496fd7ce5SGreg Kroah-Hartman #define TTY_NUMBER(tty) ((tty)->index + (tty)->driver->name_base) 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; 28596fd7ce5SGreg Kroah-Hartman int 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++; 29696fd7ce5SGreg Kroah-Hartman if (tty->count != count) { 297339f36baSPeter Hurley tty_warn(tty, "%s: tty->count(%d) != #fd's(%d)\n", 298339f36baSPeter Hurley routine, tty->count, count); 29996fd7ce5SGreg Kroah-Hartman return count; 30096fd7ce5SGreg Kroah-Hartman } 30196fd7ce5SGreg Kroah-Hartman #endif 30296fd7ce5SGreg Kroah-Hartman return 0; 30396fd7ce5SGreg Kroah-Hartman } 30496fd7ce5SGreg Kroah-Hartman 30596fd7ce5SGreg Kroah-Hartman /** 30696fd7ce5SGreg Kroah-Hartman * get_tty_driver - find device of a tty 30796fd7ce5SGreg Kroah-Hartman * @dev_t: device identifier 30896fd7ce5SGreg Kroah-Hartman * @index: returns the index of the tty 30996fd7ce5SGreg Kroah-Hartman * 31096fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a device number 31196fd7ce5SGreg Kroah-Hartman * and also passes back the index number. 31296fd7ce5SGreg Kroah-Hartman * 31396fd7ce5SGreg Kroah-Hartman * Locking: caller must hold tty_mutex 31496fd7ce5SGreg Kroah-Hartman */ 31596fd7ce5SGreg Kroah-Hartman 31696fd7ce5SGreg Kroah-Hartman static struct tty_driver *get_tty_driver(dev_t device, int *index) 31796fd7ce5SGreg Kroah-Hartman { 31896fd7ce5SGreg Kroah-Hartman struct tty_driver *p; 31996fd7ce5SGreg Kroah-Hartman 32096fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 32196fd7ce5SGreg Kroah-Hartman dev_t base = MKDEV(p->major, p->minor_start); 32296fd7ce5SGreg Kroah-Hartman if (device < base || device >= base + p->num) 32396fd7ce5SGreg Kroah-Hartman continue; 32496fd7ce5SGreg Kroah-Hartman *index = device - base; 32596fd7ce5SGreg Kroah-Hartman return tty_driver_kref_get(p); 32696fd7ce5SGreg Kroah-Hartman } 32796fd7ce5SGreg Kroah-Hartman return NULL; 32896fd7ce5SGreg Kroah-Hartman } 32996fd7ce5SGreg Kroah-Hartman 33096fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_CONSOLE_POLL 33196fd7ce5SGreg Kroah-Hartman 33296fd7ce5SGreg Kroah-Hartman /** 33396fd7ce5SGreg Kroah-Hartman * tty_find_polling_driver - find device of a polled tty 33496fd7ce5SGreg Kroah-Hartman * @name: name string to match 33596fd7ce5SGreg Kroah-Hartman * @line: pointer to resulting tty line nr 33696fd7ce5SGreg Kroah-Hartman * 33796fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a name 33896fd7ce5SGreg Kroah-Hartman * and the condition that the tty driver is capable of polled 33996fd7ce5SGreg Kroah-Hartman * operation. 34096fd7ce5SGreg Kroah-Hartman */ 34196fd7ce5SGreg Kroah-Hartman struct tty_driver *tty_find_polling_driver(char *name, int *line) 34296fd7ce5SGreg Kroah-Hartman { 34396fd7ce5SGreg Kroah-Hartman struct tty_driver *p, *res = NULL; 34496fd7ce5SGreg Kroah-Hartman int tty_line = 0; 34596fd7ce5SGreg Kroah-Hartman int len; 34696fd7ce5SGreg Kroah-Hartman char *str, *stp; 34796fd7ce5SGreg Kroah-Hartman 34896fd7ce5SGreg Kroah-Hartman for (str = name; *str; str++) 34996fd7ce5SGreg Kroah-Hartman if ((*str >= '0' && *str <= '9') || *str == ',') 35096fd7ce5SGreg Kroah-Hartman break; 35196fd7ce5SGreg Kroah-Hartman if (!*str) 35296fd7ce5SGreg Kroah-Hartman return NULL; 35396fd7ce5SGreg Kroah-Hartman 35496fd7ce5SGreg Kroah-Hartman len = str - name; 35596fd7ce5SGreg Kroah-Hartman tty_line = simple_strtoul(str, &str, 10); 35696fd7ce5SGreg Kroah-Hartman 35796fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 35896fd7ce5SGreg Kroah-Hartman /* Search through the tty devices to look for a match */ 35996fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 36096fd7ce5SGreg Kroah-Hartman if (strncmp(name, p->name, len) != 0) 36196fd7ce5SGreg Kroah-Hartman continue; 36296fd7ce5SGreg Kroah-Hartman stp = str; 36396fd7ce5SGreg Kroah-Hartman if (*stp == ',') 36496fd7ce5SGreg Kroah-Hartman stp++; 36596fd7ce5SGreg Kroah-Hartman if (*stp == '\0') 36696fd7ce5SGreg Kroah-Hartman stp = NULL; 36796fd7ce5SGreg Kroah-Hartman 36896fd7ce5SGreg Kroah-Hartman if (tty_line >= 0 && tty_line < p->num && p->ops && 36996fd7ce5SGreg Kroah-Hartman p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { 37096fd7ce5SGreg Kroah-Hartman res = tty_driver_kref_get(p); 37196fd7ce5SGreg Kroah-Hartman *line = tty_line; 37296fd7ce5SGreg Kroah-Hartman break; 37396fd7ce5SGreg Kroah-Hartman } 37496fd7ce5SGreg Kroah-Hartman } 37596fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 37696fd7ce5SGreg Kroah-Hartman 37796fd7ce5SGreg Kroah-Hartman return res; 37896fd7ce5SGreg Kroah-Hartman } 37996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_find_polling_driver); 38096fd7ce5SGreg Kroah-Hartman #endif 38196fd7ce5SGreg Kroah-Hartman 382e802ca0eSPeter Hurley static int is_ignored(int sig) 383e802ca0eSPeter Hurley { 384e802ca0eSPeter Hurley return (sigismember(¤t->blocked, sig) || 385e802ca0eSPeter Hurley current->sighand->action[sig-1].sa.sa_handler == SIG_IGN); 386e802ca0eSPeter Hurley } 387e802ca0eSPeter Hurley 38896fd7ce5SGreg Kroah-Hartman /** 38996fd7ce5SGreg Kroah-Hartman * tty_check_change - check for POSIX terminal changes 39096fd7ce5SGreg Kroah-Hartman * @tty: tty to check 39196fd7ce5SGreg Kroah-Hartman * 39296fd7ce5SGreg Kroah-Hartman * If we try to write to, or set the state of, a terminal and we're 39396fd7ce5SGreg Kroah-Hartman * not in the foreground, send a SIGTTOU. If the signal is blocked or 39496fd7ce5SGreg Kroah-Hartman * ignored, go ahead and perform the operation. (POSIX 7.2) 39596fd7ce5SGreg Kroah-Hartman * 39696fd7ce5SGreg Kroah-Hartman * Locking: ctrl_lock 39796fd7ce5SGreg Kroah-Hartman */ 39896fd7ce5SGreg Kroah-Hartman 3992812d9e9SPeter Hurley int __tty_check_change(struct tty_struct *tty, int sig) 40096fd7ce5SGreg Kroah-Hartman { 40196fd7ce5SGreg Kroah-Hartman unsigned long flags; 4022812d9e9SPeter Hurley struct pid *pgrp, *tty_pgrp; 40396fd7ce5SGreg Kroah-Hartman int ret = 0; 40496fd7ce5SGreg Kroah-Hartman 40596fd7ce5SGreg Kroah-Hartman if (current->signal->tty != tty) 40696fd7ce5SGreg Kroah-Hartman return 0; 40796fd7ce5SGreg Kroah-Hartman 4086719693cSPatrick Donnelly rcu_read_lock(); 4096719693cSPatrick Donnelly pgrp = task_pgrp(current); 4106719693cSPatrick Donnelly 41196fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 4122812d9e9SPeter Hurley tty_pgrp = tty->pgrp; 41396fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 4146719693cSPatrick Donnelly 4152812d9e9SPeter Hurley if (tty_pgrp && pgrp != tty->pgrp) { 4162812d9e9SPeter Hurley if (is_ignored(sig)) { 4172812d9e9SPeter Hurley if (sig == SIGTTIN) 41896fd7ce5SGreg Kroah-Hartman ret = -EIO; 4192812d9e9SPeter Hurley } else if (is_current_pgrp_orphaned()) 4202812d9e9SPeter Hurley ret = -EIO; 4212812d9e9SPeter Hurley else { 4222812d9e9SPeter Hurley kill_pgrp(pgrp, sig, 1); 42396fd7ce5SGreg Kroah-Hartman set_thread_flag(TIF_SIGPENDING); 42496fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 4252812d9e9SPeter Hurley } 4262812d9e9SPeter Hurley } 4276719693cSPatrick Donnelly rcu_read_unlock(); 4282812d9e9SPeter Hurley 429339f36baSPeter Hurley if (!tty_pgrp) 430339f36baSPeter Hurley tty_warn(tty, "sig=%d, tty->pgrp == NULL!\n", sig); 4312812d9e9SPeter Hurley 43296fd7ce5SGreg Kroah-Hartman return ret; 43396fd7ce5SGreg Kroah-Hartman } 43496fd7ce5SGreg Kroah-Hartman 4352812d9e9SPeter Hurley int tty_check_change(struct tty_struct *tty) 4362812d9e9SPeter Hurley { 4372812d9e9SPeter Hurley return __tty_check_change(tty, SIGTTOU); 4382812d9e9SPeter Hurley } 43996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_check_change); 44096fd7ce5SGreg Kroah-Hartman 44196fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_read(struct file *file, char __user *buf, 44296fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 44396fd7ce5SGreg Kroah-Hartman { 44496fd7ce5SGreg Kroah-Hartman return 0; 44596fd7ce5SGreg Kroah-Hartman } 44696fd7ce5SGreg Kroah-Hartman 44796fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, 44896fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 44996fd7ce5SGreg Kroah-Hartman { 45096fd7ce5SGreg Kroah-Hartman return -EIO; 45196fd7ce5SGreg Kroah-Hartman } 45296fd7ce5SGreg Kroah-Hartman 45396fd7ce5SGreg Kroah-Hartman /* No kernel lock held - none needed ;) */ 45496fd7ce5SGreg Kroah-Hartman static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait) 45596fd7ce5SGreg Kroah-Hartman { 45696fd7ce5SGreg Kroah-Hartman return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; 45796fd7ce5SGreg Kroah-Hartman } 45896fd7ce5SGreg Kroah-Hartman 45996fd7ce5SGreg Kroah-Hartman static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, 46096fd7ce5SGreg Kroah-Hartman unsigned long arg) 46196fd7ce5SGreg Kroah-Hartman { 46296fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 46396fd7ce5SGreg Kroah-Hartman } 46496fd7ce5SGreg Kroah-Hartman 46596fd7ce5SGreg Kroah-Hartman static long hung_up_tty_compat_ioctl(struct file *file, 46696fd7ce5SGreg Kroah-Hartman unsigned int cmd, unsigned long arg) 46796fd7ce5SGreg Kroah-Hartman { 46896fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 46996fd7ce5SGreg Kroah-Hartman } 47096fd7ce5SGreg Kroah-Hartman 471f557474cSPeter Hurley static int hung_up_tty_fasync(int fd, struct file *file, int on) 472f557474cSPeter Hurley { 473f557474cSPeter Hurley return -ENOTTY; 474f557474cSPeter Hurley } 475f557474cSPeter Hurley 47696fd7ce5SGreg Kroah-Hartman static const struct file_operations tty_fops = { 47796fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 47896fd7ce5SGreg Kroah-Hartman .read = tty_read, 47996fd7ce5SGreg Kroah-Hartman .write = tty_write, 48096fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 48196fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 48296fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 48396fd7ce5SGreg Kroah-Hartman .open = tty_open, 48496fd7ce5SGreg Kroah-Hartman .release = tty_release, 48596fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 48696fd7ce5SGreg Kroah-Hartman }; 48796fd7ce5SGreg Kroah-Hartman 48896fd7ce5SGreg Kroah-Hartman static const struct file_operations console_fops = { 48996fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 49096fd7ce5SGreg Kroah-Hartman .read = tty_read, 49196fd7ce5SGreg Kroah-Hartman .write = redirected_tty_write, 49296fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 49396fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 49496fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 49596fd7ce5SGreg Kroah-Hartman .open = tty_open, 49696fd7ce5SGreg Kroah-Hartman .release = tty_release, 49796fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 49896fd7ce5SGreg Kroah-Hartman }; 49996fd7ce5SGreg Kroah-Hartman 50096fd7ce5SGreg Kroah-Hartman static const struct file_operations hung_up_tty_fops = { 50196fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 50296fd7ce5SGreg Kroah-Hartman .read = hung_up_tty_read, 50396fd7ce5SGreg Kroah-Hartman .write = hung_up_tty_write, 50496fd7ce5SGreg Kroah-Hartman .poll = hung_up_tty_poll, 50596fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = hung_up_tty_ioctl, 50696fd7ce5SGreg Kroah-Hartman .compat_ioctl = hung_up_tty_compat_ioctl, 50796fd7ce5SGreg Kroah-Hartman .release = tty_release, 508f557474cSPeter Hurley .fasync = hung_up_tty_fasync, 50996fd7ce5SGreg Kroah-Hartman }; 51096fd7ce5SGreg Kroah-Hartman 51196fd7ce5SGreg Kroah-Hartman static DEFINE_SPINLOCK(redirect_lock); 51296fd7ce5SGreg Kroah-Hartman static struct file *redirect; 51396fd7ce5SGreg Kroah-Hartman 51411d9befdSPeter Hurley 51511d9befdSPeter Hurley void proc_clear_tty(struct task_struct *p) 51611d9befdSPeter Hurley { 51711d9befdSPeter Hurley unsigned long flags; 51811d9befdSPeter Hurley struct tty_struct *tty; 51911d9befdSPeter Hurley spin_lock_irqsave(&p->sighand->siglock, flags); 52011d9befdSPeter Hurley tty = p->signal->tty; 52111d9befdSPeter Hurley p->signal->tty = NULL; 52211d9befdSPeter Hurley spin_unlock_irqrestore(&p->sighand->siglock, flags); 52311d9befdSPeter Hurley tty_kref_put(tty); 52411d9befdSPeter Hurley } 52511d9befdSPeter Hurley 5262c411c11SPeter Hurley /** 5272c411c11SPeter Hurley * proc_set_tty - set the controlling terminal 5282c411c11SPeter Hurley * 5292c411c11SPeter Hurley * Only callable by the session leader and only if it does not already have 5302c411c11SPeter Hurley * a controlling terminal. 5312c411c11SPeter Hurley * 532e218eb32SPeter Hurley * Caller must hold: tty_lock() 533e218eb32SPeter Hurley * a readlock on tasklist_lock 5342c411c11SPeter Hurley * sighand lock 5352c411c11SPeter Hurley */ 536bce65f18SPeter Hurley static void __proc_set_tty(struct tty_struct *tty) 53711d9befdSPeter Hurley { 53811d9befdSPeter Hurley unsigned long flags; 539ae28fa72SPeter Hurley 54011d9befdSPeter Hurley spin_lock_irqsave(&tty->ctrl_lock, flags); 541a361858dSPeter Hurley /* 542a361858dSPeter Hurley * The session and fg pgrp references will be non-NULL if 543a361858dSPeter Hurley * tiocsctty() is stealing the controlling tty 544a361858dSPeter Hurley */ 54511d9befdSPeter Hurley put_pid(tty->session); 54611d9befdSPeter Hurley put_pid(tty->pgrp); 547bce65f18SPeter Hurley tty->pgrp = get_pid(task_pgrp(current)); 54811d9befdSPeter Hurley spin_unlock_irqrestore(&tty->ctrl_lock, flags); 549bce65f18SPeter Hurley tty->session = get_pid(task_session(current)); 550bce65f18SPeter Hurley if (current->signal->tty) { 551e2dfa3d3SPeter Hurley tty_debug(tty, "current tty %s not NULL!!\n", 552e2dfa3d3SPeter Hurley current->signal->tty->name); 553bce65f18SPeter Hurley tty_kref_put(current->signal->tty); 55411d9befdSPeter Hurley } 555bce65f18SPeter Hurley put_pid(current->signal->tty_old_pgrp); 556bce65f18SPeter Hurley current->signal->tty = tty_kref_get(tty); 557bce65f18SPeter Hurley current->signal->tty_old_pgrp = NULL; 55811d9befdSPeter Hurley } 55911d9befdSPeter Hurley 560bce65f18SPeter Hurley static void proc_set_tty(struct tty_struct *tty) 56111d9befdSPeter Hurley { 562bce65f18SPeter Hurley spin_lock_irq(¤t->sighand->siglock); 563bce65f18SPeter Hurley __proc_set_tty(tty); 564bce65f18SPeter Hurley spin_unlock_irq(¤t->sighand->siglock); 56511d9befdSPeter Hurley } 56611d9befdSPeter Hurley 56711d9befdSPeter Hurley struct tty_struct *get_current_tty(void) 56811d9befdSPeter Hurley { 56911d9befdSPeter Hurley struct tty_struct *tty; 57011d9befdSPeter Hurley unsigned long flags; 57111d9befdSPeter Hurley 57211d9befdSPeter Hurley spin_lock_irqsave(¤t->sighand->siglock, flags); 57311d9befdSPeter Hurley tty = tty_kref_get(current->signal->tty); 57411d9befdSPeter Hurley spin_unlock_irqrestore(¤t->sighand->siglock, flags); 57511d9befdSPeter Hurley return tty; 57611d9befdSPeter Hurley } 57711d9befdSPeter Hurley EXPORT_SYMBOL_GPL(get_current_tty); 57811d9befdSPeter Hurley 57911d9befdSPeter Hurley static void session_clear_tty(struct pid *session) 58011d9befdSPeter Hurley { 58111d9befdSPeter Hurley struct task_struct *p; 58211d9befdSPeter Hurley do_each_pid_task(session, PIDTYPE_SID, p) { 58311d9befdSPeter Hurley proc_clear_tty(p); 58411d9befdSPeter Hurley } while_each_pid_task(session, PIDTYPE_SID, p); 58511d9befdSPeter Hurley } 58611d9befdSPeter Hurley 58796fd7ce5SGreg Kroah-Hartman /** 58896fd7ce5SGreg Kroah-Hartman * tty_wakeup - request more data 58996fd7ce5SGreg Kroah-Hartman * @tty: terminal 59096fd7ce5SGreg Kroah-Hartman * 59196fd7ce5SGreg Kroah-Hartman * Internal and external helper for wakeups of tty. This function 59296fd7ce5SGreg Kroah-Hartman * informs the line discipline if present that the driver is ready 59396fd7ce5SGreg Kroah-Hartman * to receive more output data. 59496fd7ce5SGreg Kroah-Hartman */ 59596fd7ce5SGreg Kroah-Hartman 59696fd7ce5SGreg Kroah-Hartman void tty_wakeup(struct tty_struct *tty) 59796fd7ce5SGreg Kroah-Hartman { 59896fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 59996fd7ce5SGreg Kroah-Hartman 60096fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { 60196fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref(tty); 60296fd7ce5SGreg Kroah-Hartman if (ld) { 60396fd7ce5SGreg Kroah-Hartman if (ld->ops->write_wakeup) 60496fd7ce5SGreg Kroah-Hartman ld->ops->write_wakeup(tty); 60596fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 60696fd7ce5SGreg Kroah-Hartman } 60796fd7ce5SGreg Kroah-Hartman } 60896fd7ce5SGreg Kroah-Hartman wake_up_interruptible_poll(&tty->write_wait, POLLOUT); 60996fd7ce5SGreg Kroah-Hartman } 61096fd7ce5SGreg Kroah-Hartman 61196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_wakeup); 61296fd7ce5SGreg Kroah-Hartman 61396fd7ce5SGreg Kroah-Hartman /** 614ea648a47SPeter Hurley * tty_signal_session_leader - sends SIGHUP to session leader 615f91e2590SPeter Hurley * @tty controlling tty 616f91e2590SPeter Hurley * @exit_session if non-zero, signal all foreground group processes 617ea648a47SPeter Hurley * 618f91e2590SPeter Hurley * Send SIGHUP and SIGCONT to the session leader and its process group. 619f91e2590SPeter Hurley * Optionally, signal all processes in the foreground process group. 620ea648a47SPeter Hurley * 621ea648a47SPeter Hurley * Returns the number of processes in the session with this tty 622ea648a47SPeter Hurley * as their controlling terminal. This value is used to drop 623ea648a47SPeter Hurley * tty references for those processes. 624ea648a47SPeter Hurley */ 625f91e2590SPeter Hurley static int tty_signal_session_leader(struct tty_struct *tty, int exit_session) 626ea648a47SPeter Hurley { 627ea648a47SPeter Hurley struct task_struct *p; 628ea648a47SPeter Hurley int refs = 0; 629f91e2590SPeter Hurley struct pid *tty_pgrp = NULL; 630ea648a47SPeter Hurley 631ea648a47SPeter Hurley read_lock(&tasklist_lock); 632ea648a47SPeter Hurley if (tty->session) { 633ea648a47SPeter Hurley do_each_pid_task(tty->session, PIDTYPE_SID, p) { 634ea648a47SPeter Hurley spin_lock_irq(&p->sighand->siglock); 635ea648a47SPeter Hurley if (p->signal->tty == tty) { 636ea648a47SPeter Hurley p->signal->tty = NULL; 637ea648a47SPeter Hurley /* We defer the dereferences outside fo 638ea648a47SPeter Hurley the tasklist lock */ 639ea648a47SPeter Hurley refs++; 640ea648a47SPeter Hurley } 641ea648a47SPeter Hurley if (!p->signal->leader) { 642ea648a47SPeter Hurley spin_unlock_irq(&p->sighand->siglock); 643ea648a47SPeter Hurley continue; 644ea648a47SPeter Hurley } 645ea648a47SPeter Hurley __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); 646ea648a47SPeter Hurley __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); 647ea648a47SPeter Hurley put_pid(p->signal->tty_old_pgrp); /* A noop */ 648bc30c3b2SPeter Hurley spin_lock(&tty->ctrl_lock); 649f91e2590SPeter Hurley tty_pgrp = get_pid(tty->pgrp); 650ea648a47SPeter Hurley if (tty->pgrp) 651ea648a47SPeter Hurley p->signal->tty_old_pgrp = get_pid(tty->pgrp); 652bc30c3b2SPeter Hurley spin_unlock(&tty->ctrl_lock); 653ea648a47SPeter Hurley spin_unlock_irq(&p->sighand->siglock); 654ea648a47SPeter Hurley } while_each_pid_task(tty->session, PIDTYPE_SID, p); 655ea648a47SPeter Hurley } 656ea648a47SPeter Hurley read_unlock(&tasklist_lock); 657ea648a47SPeter Hurley 658f91e2590SPeter Hurley if (tty_pgrp) { 659f91e2590SPeter Hurley if (exit_session) 660f91e2590SPeter Hurley kill_pgrp(tty_pgrp, SIGHUP, exit_session); 661f91e2590SPeter Hurley put_pid(tty_pgrp); 662f91e2590SPeter Hurley } 663f91e2590SPeter Hurley 664ea648a47SPeter Hurley return refs; 665ea648a47SPeter Hurley } 666ea648a47SPeter Hurley 667ea648a47SPeter Hurley /** 66896fd7ce5SGreg Kroah-Hartman * __tty_hangup - actual handler for hangup events 66996fd7ce5SGreg Kroah-Hartman * @work: tty device 67096fd7ce5SGreg Kroah-Hartman * 671ef4f527cSKevin Cernekee * This can be called by a "kworker" kernel thread. That is process 67296fd7ce5SGreg Kroah-Hartman * synchronous but doesn't hold any locks, so we need to make sure we 67396fd7ce5SGreg Kroah-Hartman * have the appropriate locks for what we're doing. 67496fd7ce5SGreg Kroah-Hartman * 67596fd7ce5SGreg Kroah-Hartman * The hangup event clears any pending redirections onto the hung up 67696fd7ce5SGreg Kroah-Hartman * device. It ensures future writes will error and it does the needed 67796fd7ce5SGreg Kroah-Hartman * line discipline hangup and signal delivery. The tty object itself 67896fd7ce5SGreg Kroah-Hartman * remains intact. 67996fd7ce5SGreg Kroah-Hartman * 68096fd7ce5SGreg Kroah-Hartman * Locking: 68196fd7ce5SGreg Kroah-Hartman * BTM 68296fd7ce5SGreg Kroah-Hartman * redirect lock for undoing redirection 68396fd7ce5SGreg Kroah-Hartman * file list lock for manipulating list of ttys 684137084bbSPeter Hurley * tty_ldiscs_lock from called functions 6856a1c0680SPeter Hurley * termios_rwsem resetting termios data 68696fd7ce5SGreg Kroah-Hartman * tasklist_lock to walk task list for hangup event 68796fd7ce5SGreg Kroah-Hartman * ->siglock to protect ->signal/->sighand 68896fd7ce5SGreg Kroah-Hartman */ 689f91e2590SPeter Hurley static void __tty_hangup(struct tty_struct *tty, int exit_session) 69096fd7ce5SGreg Kroah-Hartman { 69196fd7ce5SGreg Kroah-Hartman struct file *cons_filp = NULL; 69296fd7ce5SGreg Kroah-Hartman struct file *filp, *f = NULL; 69396fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 69496fd7ce5SGreg Kroah-Hartman int closecount = 0, n; 695ea648a47SPeter Hurley int refs; 69696fd7ce5SGreg Kroah-Hartman 69796fd7ce5SGreg Kroah-Hartman if (!tty) 69896fd7ce5SGreg Kroah-Hartman return; 69996fd7ce5SGreg Kroah-Hartman 70096fd7ce5SGreg Kroah-Hartman 70196fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 70296fd7ce5SGreg Kroah-Hartman if (redirect && file_tty(redirect) == tty) { 70396fd7ce5SGreg Kroah-Hartman f = redirect; 70496fd7ce5SGreg Kroah-Hartman redirect = NULL; 70596fd7ce5SGreg Kroah-Hartman } 70696fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 70796fd7ce5SGreg Kroah-Hartman 70889c8d91eSAlan Cox tty_lock(tty); 70996fd7ce5SGreg Kroah-Hartman 710cb50e523SPeter Hurley if (test_bit(TTY_HUPPED, &tty->flags)) { 711cb50e523SPeter Hurley tty_unlock(tty); 712cb50e523SPeter Hurley return; 713cb50e523SPeter Hurley } 714cb50e523SPeter Hurley 71596fd7ce5SGreg Kroah-Hartman /* inuse_filps is protected by the single tty lock, 71696fd7ce5SGreg Kroah-Hartman this really needs to change if we want to flush the 71796fd7ce5SGreg Kroah-Hartman workqueue with the lock held */ 71896fd7ce5SGreg Kroah-Hartman check_tty_count(tty, "tty_hangup"); 71996fd7ce5SGreg Kroah-Hartman 7204a510969SPeter Hurley spin_lock(&tty->files_lock); 72196fd7ce5SGreg Kroah-Hartman /* This breaks for file handles being sent over AF_UNIX sockets ? */ 72296fd7ce5SGreg Kroah-Hartman list_for_each_entry(priv, &tty->tty_files, list) { 72396fd7ce5SGreg Kroah-Hartman filp = priv->file; 72496fd7ce5SGreg Kroah-Hartman if (filp->f_op->write == redirected_tty_write) 72596fd7ce5SGreg Kroah-Hartman cons_filp = filp; 72696fd7ce5SGreg Kroah-Hartman if (filp->f_op->write != tty_write) 72796fd7ce5SGreg Kroah-Hartman continue; 72896fd7ce5SGreg Kroah-Hartman closecount++; 72996fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); /* can't block */ 73096fd7ce5SGreg Kroah-Hartman filp->f_op = &hung_up_tty_fops; 73196fd7ce5SGreg Kroah-Hartman } 7324a510969SPeter Hurley spin_unlock(&tty->files_lock); 73396fd7ce5SGreg Kroah-Hartman 73425fdf243SPeter Hurley refs = tty_signal_session_leader(tty, exit_session); 73525fdf243SPeter Hurley /* Account for the p->signal references we killed */ 73625fdf243SPeter Hurley while (refs--) 73725fdf243SPeter Hurley tty_kref_put(tty); 73825fdf243SPeter Hurley 739892d1fa7SPeter Hurley tty_ldisc_hangup(tty, cons_filp != NULL); 74096fd7ce5SGreg Kroah-Hartman 74120cc225bSPeter Hurley spin_lock_irq(&tty->ctrl_lock); 74296fd7ce5SGreg Kroah-Hartman clear_bit(TTY_THROTTLED, &tty->flags); 74396fd7ce5SGreg Kroah-Hartman clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 74496fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 74596fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 74696fd7ce5SGreg Kroah-Hartman tty->session = NULL; 74796fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 74896fd7ce5SGreg Kroah-Hartman tty->ctrl_status = 0; 74920cc225bSPeter Hurley spin_unlock_irq(&tty->ctrl_lock); 75096fd7ce5SGreg Kroah-Hartman 75196fd7ce5SGreg Kroah-Hartman /* 75296fd7ce5SGreg Kroah-Hartman * If one of the devices matches a console pointer, we 75396fd7ce5SGreg Kroah-Hartman * cannot just call hangup() because that will cause 75496fd7ce5SGreg Kroah-Hartman * tty->count and state->count to go out of sync. 75596fd7ce5SGreg Kroah-Hartman * So we just call close() the right number of times. 75696fd7ce5SGreg Kroah-Hartman */ 75796fd7ce5SGreg Kroah-Hartman if (cons_filp) { 75896fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 75996fd7ce5SGreg Kroah-Hartman for (n = 0; n < closecount; n++) 76096fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, cons_filp); 76196fd7ce5SGreg Kroah-Hartman } else if (tty->ops->hangup) 7627c6d340fSPeter Hurley tty->ops->hangup(tty); 76396fd7ce5SGreg Kroah-Hartman /* 764892d1fa7SPeter Hurley * We don't want to have driver/ldisc interactions beyond the ones 765892d1fa7SPeter Hurley * we did here. The driver layer expects no calls after ->hangup() 766892d1fa7SPeter Hurley * from the ldisc side, which is now guaranteed. 76796fd7ce5SGreg Kroah-Hartman */ 76896fd7ce5SGreg Kroah-Hartman set_bit(TTY_HUPPED, &tty->flags); 76989c8d91eSAlan Cox tty_unlock(tty); 77096fd7ce5SGreg Kroah-Hartman 77196fd7ce5SGreg Kroah-Hartman if (f) 77296fd7ce5SGreg Kroah-Hartman fput(f); 77396fd7ce5SGreg Kroah-Hartman } 77496fd7ce5SGreg Kroah-Hartman 77596fd7ce5SGreg Kroah-Hartman static void do_tty_hangup(struct work_struct *work) 77696fd7ce5SGreg Kroah-Hartman { 77796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 77896fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 77996fd7ce5SGreg Kroah-Hartman 780f91e2590SPeter Hurley __tty_hangup(tty, 0); 78196fd7ce5SGreg Kroah-Hartman } 78296fd7ce5SGreg Kroah-Hartman 78396fd7ce5SGreg Kroah-Hartman /** 78496fd7ce5SGreg Kroah-Hartman * tty_hangup - trigger a hangup event 78596fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 78696fd7ce5SGreg Kroah-Hartman * 78796fd7ce5SGreg Kroah-Hartman * A carrier loss (virtual or otherwise) has occurred on this like 78896fd7ce5SGreg Kroah-Hartman * schedule a hangup sequence to run after this event. 78996fd7ce5SGreg Kroah-Hartman */ 79096fd7ce5SGreg Kroah-Hartman 79196fd7ce5SGreg Kroah-Hartman void tty_hangup(struct tty_struct *tty) 79296fd7ce5SGreg Kroah-Hartman { 793d435cefeSPeter Hurley tty_debug_hangup(tty, "hangup\n"); 79496fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 79596fd7ce5SGreg Kroah-Hartman } 79696fd7ce5SGreg Kroah-Hartman 79796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hangup); 79896fd7ce5SGreg Kroah-Hartman 79996fd7ce5SGreg Kroah-Hartman /** 80096fd7ce5SGreg Kroah-Hartman * tty_vhangup - process vhangup 80196fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 80296fd7ce5SGreg Kroah-Hartman * 80396fd7ce5SGreg Kroah-Hartman * The user has asked via system call for the terminal to be hung up. 80496fd7ce5SGreg Kroah-Hartman * We do this synchronously so that when the syscall returns the process 80596fd7ce5SGreg Kroah-Hartman * is complete. That guarantee is necessary for security reasons. 80696fd7ce5SGreg Kroah-Hartman */ 80796fd7ce5SGreg Kroah-Hartman 80896fd7ce5SGreg Kroah-Hartman void tty_vhangup(struct tty_struct *tty) 80996fd7ce5SGreg Kroah-Hartman { 810d435cefeSPeter Hurley tty_debug_hangup(tty, "vhangup\n"); 811f91e2590SPeter Hurley __tty_hangup(tty, 0); 81296fd7ce5SGreg Kroah-Hartman } 81396fd7ce5SGreg Kroah-Hartman 81496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_vhangup); 81596fd7ce5SGreg Kroah-Hartman 81696fd7ce5SGreg Kroah-Hartman 81796fd7ce5SGreg Kroah-Hartman /** 81896fd7ce5SGreg Kroah-Hartman * tty_vhangup_self - process vhangup for own ctty 81996fd7ce5SGreg Kroah-Hartman * 82096fd7ce5SGreg Kroah-Hartman * Perform a vhangup on the current controlling tty 82196fd7ce5SGreg Kroah-Hartman */ 82296fd7ce5SGreg Kroah-Hartman 82396fd7ce5SGreg Kroah-Hartman void tty_vhangup_self(void) 82496fd7ce5SGreg Kroah-Hartman { 82596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 82696fd7ce5SGreg Kroah-Hartman 82796fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 82896fd7ce5SGreg Kroah-Hartman if (tty) { 82996fd7ce5SGreg Kroah-Hartman tty_vhangup(tty); 83096fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 83196fd7ce5SGreg Kroah-Hartman } 83296fd7ce5SGreg Kroah-Hartman } 83396fd7ce5SGreg Kroah-Hartman 83496fd7ce5SGreg Kroah-Hartman /** 835f91e2590SPeter Hurley * tty_vhangup_session - hangup session leader exit 836f91e2590SPeter Hurley * @tty: tty to hangup 837f91e2590SPeter Hurley * 838f91e2590SPeter Hurley * The session leader is exiting and hanging up its controlling terminal. 839f91e2590SPeter Hurley * Every process in the foreground process group is signalled SIGHUP. 840f91e2590SPeter Hurley * 841f91e2590SPeter Hurley * We do this synchronously so that when the syscall returns the process 842f91e2590SPeter Hurley * is complete. That guarantee is necessary for security reasons. 843f91e2590SPeter Hurley */ 844f91e2590SPeter Hurley 84544a459fdSChanglong Xie static void tty_vhangup_session(struct tty_struct *tty) 846f91e2590SPeter Hurley { 847d435cefeSPeter Hurley tty_debug_hangup(tty, "session hangup\n"); 848f91e2590SPeter Hurley __tty_hangup(tty, 1); 849f91e2590SPeter Hurley } 850f91e2590SPeter Hurley 851f91e2590SPeter Hurley /** 85296fd7ce5SGreg Kroah-Hartman * tty_hung_up_p - was tty hung up 85396fd7ce5SGreg Kroah-Hartman * @filp: file pointer of tty 85496fd7ce5SGreg Kroah-Hartman * 85596fd7ce5SGreg Kroah-Hartman * Return true if the tty has been subject to a vhangup or a carrier 85696fd7ce5SGreg Kroah-Hartman * loss 85796fd7ce5SGreg Kroah-Hartman */ 85896fd7ce5SGreg Kroah-Hartman 85996fd7ce5SGreg Kroah-Hartman int tty_hung_up_p(struct file *filp) 86096fd7ce5SGreg Kroah-Hartman { 86196fd7ce5SGreg Kroah-Hartman return (filp->f_op == &hung_up_tty_fops); 86296fd7ce5SGreg Kroah-Hartman } 86396fd7ce5SGreg Kroah-Hartman 86496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hung_up_p); 86596fd7ce5SGreg Kroah-Hartman 86696fd7ce5SGreg Kroah-Hartman /** 86796fd7ce5SGreg Kroah-Hartman * disassociate_ctty - disconnect controlling tty 86896fd7ce5SGreg Kroah-Hartman * @on_exit: true if exiting so need to "hang up" the session 86996fd7ce5SGreg Kroah-Hartman * 87096fd7ce5SGreg Kroah-Hartman * This function is typically called only by the session leader, when 87196fd7ce5SGreg Kroah-Hartman * it wants to disassociate itself from its controlling tty. 87296fd7ce5SGreg Kroah-Hartman * 87396fd7ce5SGreg Kroah-Hartman * It performs the following functions: 87496fd7ce5SGreg Kroah-Hartman * (1) Sends a SIGHUP and SIGCONT to the foreground process group 87596fd7ce5SGreg Kroah-Hartman * (2) Clears the tty from being controlling the session 87696fd7ce5SGreg Kroah-Hartman * (3) Clears the controlling tty for all processes in the 87796fd7ce5SGreg Kroah-Hartman * session group. 87896fd7ce5SGreg Kroah-Hartman * 87996fd7ce5SGreg Kroah-Hartman * The argument on_exit is set to 1 if called when a process is 88096fd7ce5SGreg Kroah-Hartman * exiting; it is 0 if called by the ioctl TIOCNOTTY. 88196fd7ce5SGreg Kroah-Hartman * 88296fd7ce5SGreg Kroah-Hartman * Locking: 88396fd7ce5SGreg Kroah-Hartman * BTM is taken for hysterical raisins, and held when 88496fd7ce5SGreg Kroah-Hartman * called from no_tty(). 88596fd7ce5SGreg Kroah-Hartman * tty_mutex is taken to protect tty 88696fd7ce5SGreg Kroah-Hartman * ->siglock is taken to protect ->signal/->sighand 88796fd7ce5SGreg Kroah-Hartman * tasklist_lock is taken to walk process list for sessions 88896fd7ce5SGreg Kroah-Hartman * ->siglock is taken to protect ->signal/->sighand 88996fd7ce5SGreg Kroah-Hartman */ 89096fd7ce5SGreg Kroah-Hartman 89196fd7ce5SGreg Kroah-Hartman void disassociate_ctty(int on_exit) 89296fd7ce5SGreg Kroah-Hartman { 89396fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 89496fd7ce5SGreg Kroah-Hartman 89596fd7ce5SGreg Kroah-Hartman if (!current->signal->leader) 89696fd7ce5SGreg Kroah-Hartman return; 89796fd7ce5SGreg Kroah-Hartman 89896fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 89996fd7ce5SGreg Kroah-Hartman if (tty) { 900f91e2590SPeter Hurley if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) { 901f91e2590SPeter Hurley tty_vhangup_session(tty); 902f91e2590SPeter Hurley } else { 903f91e2590SPeter Hurley struct pid *tty_pgrp = tty_get_pgrp(tty); 9041411dc4aSJiri Slaby if (tty_pgrp) { 9051411dc4aSJiri Slaby kill_pgrp(tty_pgrp, SIGHUP, on_exit); 90603e12617SOleg Nesterov if (!on_exit) 9071411dc4aSJiri Slaby kill_pgrp(tty_pgrp, SIGCONT, on_exit); 9081411dc4aSJiri Slaby put_pid(tty_pgrp); 9091411dc4aSJiri Slaby } 910f91e2590SPeter Hurley } 911f91e2590SPeter Hurley tty_kref_put(tty); 912f91e2590SPeter Hurley 91396fd7ce5SGreg Kroah-Hartman } else if (on_exit) { 91496fd7ce5SGreg Kroah-Hartman struct pid *old_pgrp; 91596fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 91696fd7ce5SGreg Kroah-Hartman old_pgrp = current->signal->tty_old_pgrp; 91796fd7ce5SGreg Kroah-Hartman current->signal->tty_old_pgrp = NULL; 91896fd7ce5SGreg Kroah-Hartman spin_unlock_irq(¤t->sighand->siglock); 91996fd7ce5SGreg Kroah-Hartman if (old_pgrp) { 92096fd7ce5SGreg Kroah-Hartman kill_pgrp(old_pgrp, SIGHUP, on_exit); 92196fd7ce5SGreg Kroah-Hartman kill_pgrp(old_pgrp, SIGCONT, on_exit); 92296fd7ce5SGreg Kroah-Hartman put_pid(old_pgrp); 92396fd7ce5SGreg Kroah-Hartman } 92496fd7ce5SGreg Kroah-Hartman return; 92596fd7ce5SGreg Kroah-Hartman } 92696fd7ce5SGreg Kroah-Hartman 92796fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 92896fd7ce5SGreg Kroah-Hartman put_pid(current->signal->tty_old_pgrp); 92996fd7ce5SGreg Kroah-Hartman current->signal->tty_old_pgrp = NULL; 93096fd7ce5SGreg Kroah-Hartman 931c70dbb1eSChen Tingjie tty = tty_kref_get(current->signal->tty); 93296fd7ce5SGreg Kroah-Hartman if (tty) { 93396fd7ce5SGreg Kroah-Hartman unsigned long flags; 93496fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 93596fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 93696fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 93796fd7ce5SGreg Kroah-Hartman tty->session = NULL; 93896fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 93996fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 94096fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 941accff793SPeter Hurley } else 942accff793SPeter Hurley tty_debug_hangup(tty, "no current tty\n"); 94396fd7ce5SGreg Kroah-Hartman 944c70dbb1eSChen Tingjie spin_unlock_irq(¤t->sighand->siglock); 94596fd7ce5SGreg Kroah-Hartman /* Now clear signal->tty under the lock */ 94696fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 94796fd7ce5SGreg Kroah-Hartman session_clear_tty(task_session(current)); 94896fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 94996fd7ce5SGreg Kroah-Hartman } 95096fd7ce5SGreg Kroah-Hartman 95196fd7ce5SGreg Kroah-Hartman /** 95296fd7ce5SGreg Kroah-Hartman * 95396fd7ce5SGreg Kroah-Hartman * no_tty - Ensure the current process does not have a controlling tty 95496fd7ce5SGreg Kroah-Hartman */ 95596fd7ce5SGreg Kroah-Hartman void no_tty(void) 95696fd7ce5SGreg Kroah-Hartman { 9573af502b9SAlan Cox /* FIXME: Review locking here. The tty_lock never covered any race 9583af502b9SAlan Cox between a new association and proc_clear_tty but possible we need 9593af502b9SAlan Cox to protect against this anyway */ 96096fd7ce5SGreg Kroah-Hartman struct task_struct *tsk = current; 96196fd7ce5SGreg Kroah-Hartman disassociate_ctty(0); 96296fd7ce5SGreg Kroah-Hartman proc_clear_tty(tsk); 96396fd7ce5SGreg Kroah-Hartman } 96496fd7ce5SGreg Kroah-Hartman 96596fd7ce5SGreg Kroah-Hartman 96696fd7ce5SGreg Kroah-Hartman /** 96796fd7ce5SGreg Kroah-Hartman * stop_tty - propagate flow control 96896fd7ce5SGreg Kroah-Hartman * @tty: tty to stop 96996fd7ce5SGreg Kroah-Hartman * 97001adc807SPeter Hurley * Perform flow control to the driver. May be called 97196fd7ce5SGreg Kroah-Hartman * on an already stopped device and will not re-call the driver 97296fd7ce5SGreg Kroah-Hartman * method. 97396fd7ce5SGreg Kroah-Hartman * 97496fd7ce5SGreg Kroah-Hartman * This functionality is used by both the line disciplines for 97596fd7ce5SGreg Kroah-Hartman * halting incoming flow and by the driver. It may therefore be 97696fd7ce5SGreg Kroah-Hartman * called from any context, may be under the tty atomic_write_lock 97796fd7ce5SGreg Kroah-Hartman * but not always. 97896fd7ce5SGreg Kroah-Hartman * 97996fd7ce5SGreg Kroah-Hartman * Locking: 980f9e053dcSPeter Hurley * flow_lock 98196fd7ce5SGreg Kroah-Hartman */ 98296fd7ce5SGreg Kroah-Hartman 983f9e053dcSPeter Hurley void __stop_tty(struct tty_struct *tty) 98496fd7ce5SGreg Kroah-Hartman { 985f9e053dcSPeter Hurley if (tty->stopped) 98696fd7ce5SGreg Kroah-Hartman return; 98796fd7ce5SGreg Kroah-Hartman tty->stopped = 1; 98896fd7ce5SGreg Kroah-Hartman if (tty->ops->stop) 989c961bfb1SPeter Hurley tty->ops->stop(tty); 99096fd7ce5SGreg Kroah-Hartman } 99196fd7ce5SGreg Kroah-Hartman 992f9e053dcSPeter Hurley void stop_tty(struct tty_struct *tty) 993f9e053dcSPeter Hurley { 994f9e053dcSPeter Hurley unsigned long flags; 995f9e053dcSPeter Hurley 996f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 997f9e053dcSPeter Hurley __stop_tty(tty); 998f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 999f9e053dcSPeter Hurley } 100096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(stop_tty); 100196fd7ce5SGreg Kroah-Hartman 100296fd7ce5SGreg Kroah-Hartman /** 100396fd7ce5SGreg Kroah-Hartman * start_tty - propagate flow control 100496fd7ce5SGreg Kroah-Hartman * @tty: tty to start 100596fd7ce5SGreg Kroah-Hartman * 100601adc807SPeter Hurley * Start a tty that has been stopped if at all possible. If this 100701adc807SPeter Hurley * tty was previous stopped and is now being started, the driver 100801adc807SPeter Hurley * start method is invoked and the line discipline woken. 100996fd7ce5SGreg Kroah-Hartman * 101096fd7ce5SGreg Kroah-Hartman * Locking: 1011f9e053dcSPeter Hurley * flow_lock 101296fd7ce5SGreg Kroah-Hartman */ 101396fd7ce5SGreg Kroah-Hartman 1014f9e053dcSPeter Hurley void __start_tty(struct tty_struct *tty) 101596fd7ce5SGreg Kroah-Hartman { 1016f9e053dcSPeter Hurley if (!tty->stopped || tty->flow_stopped) 101796fd7ce5SGreg Kroah-Hartman return; 101896fd7ce5SGreg Kroah-Hartman tty->stopped = 0; 101996fd7ce5SGreg Kroah-Hartman if (tty->ops->start) 1020c961bfb1SPeter Hurley tty->ops->start(tty); 102196fd7ce5SGreg Kroah-Hartman tty_wakeup(tty); 102296fd7ce5SGreg Kroah-Hartman } 102396fd7ce5SGreg Kroah-Hartman 1024f9e053dcSPeter Hurley void start_tty(struct tty_struct *tty) 1025f9e053dcSPeter Hurley { 1026f9e053dcSPeter Hurley unsigned long flags; 1027f9e053dcSPeter Hurley 1028f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 1029f9e053dcSPeter Hurley __start_tty(tty); 1030f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 1031f9e053dcSPeter Hurley } 103296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(start_tty); 103396fd7ce5SGreg Kroah-Hartman 103437b7f3c7SJiri Slaby static void tty_update_time(struct timespec *time) 103537b7f3c7SJiri Slaby { 1036f0bf0bd0SJiri Slaby unsigned long sec = get_seconds(); 1037fbf47635SGreg Kroah-Hartman 1038fbf47635SGreg Kroah-Hartman /* 1039fbf47635SGreg Kroah-Hartman * We only care if the two values differ in anything other than the 1040fbf47635SGreg Kroah-Hartman * lower three bits (i.e every 8 seconds). If so, then we can update 1041fbf47635SGreg Kroah-Hartman * the time of the tty device, otherwise it could be construded as a 1042fbf47635SGreg Kroah-Hartman * security leak to let userspace know the exact timing of the tty. 1043fbf47635SGreg Kroah-Hartman */ 1044fbf47635SGreg Kroah-Hartman if ((sec ^ time->tv_sec) & ~7) 104537b7f3c7SJiri Slaby time->tv_sec = sec; 104637b7f3c7SJiri Slaby } 104737b7f3c7SJiri Slaby 104896fd7ce5SGreg Kroah-Hartman /** 104996fd7ce5SGreg Kroah-Hartman * tty_read - read method for tty device files 105096fd7ce5SGreg Kroah-Hartman * @file: pointer to tty file 105196fd7ce5SGreg Kroah-Hartman * @buf: user buffer 105296fd7ce5SGreg Kroah-Hartman * @count: size of user buffer 105396fd7ce5SGreg Kroah-Hartman * @ppos: unused 105496fd7ce5SGreg Kroah-Hartman * 105596fd7ce5SGreg Kroah-Hartman * Perform the read system call function on this terminal device. Checks 105696fd7ce5SGreg Kroah-Hartman * for hung up devices before calling the line discipline method. 105796fd7ce5SGreg Kroah-Hartman * 105896fd7ce5SGreg Kroah-Hartman * Locking: 105996fd7ce5SGreg Kroah-Hartman * Locks the line discipline internally while needed. Multiple 106096fd7ce5SGreg Kroah-Hartman * read calls may be outstanding in parallel. 106196fd7ce5SGreg Kroah-Hartman */ 106296fd7ce5SGreg Kroah-Hartman 106396fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *file, char __user *buf, size_t count, 106496fd7ce5SGreg Kroah-Hartman loff_t *ppos) 106596fd7ce5SGreg Kroah-Hartman { 106696fd7ce5SGreg Kroah-Hartman int i; 106737b7f3c7SJiri Slaby struct inode *inode = file_inode(file); 106896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 106996fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 107096fd7ce5SGreg Kroah-Hartman 107137b7f3c7SJiri Slaby if (tty_paranoia_check(tty, inode, "tty_read")) 107296fd7ce5SGreg Kroah-Hartman return -EIO; 107318900ca6SPeter Hurley if (!tty || tty_io_error(tty)) 107496fd7ce5SGreg Kroah-Hartman return -EIO; 107596fd7ce5SGreg Kroah-Hartman 107696fd7ce5SGreg Kroah-Hartman /* We want to wait for the line discipline to sort out in this 107796fd7ce5SGreg Kroah-Hartman situation */ 107896fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 1079e55afd11SPeter Hurley if (!ld) 1080e55afd11SPeter Hurley return hung_up_tty_read(file, buf, count, ppos); 108196fd7ce5SGreg Kroah-Hartman if (ld->ops->read) 1082c961bfb1SPeter Hurley i = ld->ops->read(tty, file, buf, count); 108396fd7ce5SGreg Kroah-Hartman else 108496fd7ce5SGreg Kroah-Hartman i = -EIO; 108596fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 1086b0de59b5SJiri Slaby 108737b7f3c7SJiri Slaby if (i > 0) 108837b7f3c7SJiri Slaby tty_update_time(&inode->i_atime); 108937b7f3c7SJiri Slaby 109096fd7ce5SGreg Kroah-Hartman return i; 109196fd7ce5SGreg Kroah-Hartman } 109296fd7ce5SGreg Kroah-Hartman 1093136d5258SPeter Hurley static void tty_write_unlock(struct tty_struct *tty) 109496fd7ce5SGreg Kroah-Hartman { 109596fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty->atomic_write_lock); 109696fd7ce5SGreg Kroah-Hartman wake_up_interruptible_poll(&tty->write_wait, POLLOUT); 109796fd7ce5SGreg Kroah-Hartman } 109896fd7ce5SGreg Kroah-Hartman 1099136d5258SPeter Hurley static int tty_write_lock(struct tty_struct *tty, int ndelay) 110096fd7ce5SGreg Kroah-Hartman { 110196fd7ce5SGreg Kroah-Hartman if (!mutex_trylock(&tty->atomic_write_lock)) { 110296fd7ce5SGreg Kroah-Hartman if (ndelay) 110396fd7ce5SGreg Kroah-Hartman return -EAGAIN; 110496fd7ce5SGreg Kroah-Hartman if (mutex_lock_interruptible(&tty->atomic_write_lock)) 110596fd7ce5SGreg Kroah-Hartman return -ERESTARTSYS; 110696fd7ce5SGreg Kroah-Hartman } 110796fd7ce5SGreg Kroah-Hartman return 0; 110896fd7ce5SGreg Kroah-Hartman } 110996fd7ce5SGreg Kroah-Hartman 111096fd7ce5SGreg Kroah-Hartman /* 111196fd7ce5SGreg Kroah-Hartman * Split writes up in sane blocksizes to avoid 111296fd7ce5SGreg Kroah-Hartman * denial-of-service type attacks 111396fd7ce5SGreg Kroah-Hartman */ 111496fd7ce5SGreg Kroah-Hartman static inline ssize_t do_tty_write( 111596fd7ce5SGreg Kroah-Hartman ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), 111696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty, 111796fd7ce5SGreg Kroah-Hartman struct file *file, 111896fd7ce5SGreg Kroah-Hartman const char __user *buf, 111996fd7ce5SGreg Kroah-Hartman size_t count) 112096fd7ce5SGreg Kroah-Hartman { 112196fd7ce5SGreg Kroah-Hartman ssize_t ret, written = 0; 112296fd7ce5SGreg Kroah-Hartman unsigned int chunk; 112396fd7ce5SGreg Kroah-Hartman 112496fd7ce5SGreg Kroah-Hartman ret = tty_write_lock(tty, file->f_flags & O_NDELAY); 112596fd7ce5SGreg Kroah-Hartman if (ret < 0) 112696fd7ce5SGreg Kroah-Hartman return ret; 112796fd7ce5SGreg Kroah-Hartman 112896fd7ce5SGreg Kroah-Hartman /* 112996fd7ce5SGreg Kroah-Hartman * We chunk up writes into a temporary buffer. This 113096fd7ce5SGreg Kroah-Hartman * simplifies low-level drivers immensely, since they 113196fd7ce5SGreg Kroah-Hartman * don't have locking issues and user mode accesses. 113296fd7ce5SGreg Kroah-Hartman * 113396fd7ce5SGreg Kroah-Hartman * But if TTY_NO_WRITE_SPLIT is set, we should use a 113496fd7ce5SGreg Kroah-Hartman * big chunk-size.. 113596fd7ce5SGreg Kroah-Hartman * 113696fd7ce5SGreg Kroah-Hartman * The default chunk-size is 2kB, because the NTTY 113796fd7ce5SGreg Kroah-Hartman * layer has problems with bigger chunks. It will 113896fd7ce5SGreg Kroah-Hartman * claim to be able to handle more characters than 113996fd7ce5SGreg Kroah-Hartman * it actually does. 114096fd7ce5SGreg Kroah-Hartman * 114196fd7ce5SGreg Kroah-Hartman * FIXME: This can probably go away now except that 64K chunks 114296fd7ce5SGreg Kroah-Hartman * are too likely to fail unless switched to vmalloc... 114396fd7ce5SGreg Kroah-Hartman */ 114496fd7ce5SGreg Kroah-Hartman chunk = 2048; 114596fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) 114696fd7ce5SGreg Kroah-Hartman chunk = 65536; 114796fd7ce5SGreg Kroah-Hartman if (count < chunk) 114896fd7ce5SGreg Kroah-Hartman chunk = count; 114996fd7ce5SGreg Kroah-Hartman 115096fd7ce5SGreg Kroah-Hartman /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ 115196fd7ce5SGreg Kroah-Hartman if (tty->write_cnt < chunk) { 115296fd7ce5SGreg Kroah-Hartman unsigned char *buf_chunk; 115396fd7ce5SGreg Kroah-Hartman 115496fd7ce5SGreg Kroah-Hartman if (chunk < 1024) 115596fd7ce5SGreg Kroah-Hartman chunk = 1024; 115696fd7ce5SGreg Kroah-Hartman 115796fd7ce5SGreg Kroah-Hartman buf_chunk = kmalloc(chunk, GFP_KERNEL); 115896fd7ce5SGreg Kroah-Hartman if (!buf_chunk) { 115996fd7ce5SGreg Kroah-Hartman ret = -ENOMEM; 116096fd7ce5SGreg Kroah-Hartman goto out; 116196fd7ce5SGreg Kroah-Hartman } 116296fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 116396fd7ce5SGreg Kroah-Hartman tty->write_cnt = chunk; 116496fd7ce5SGreg Kroah-Hartman tty->write_buf = buf_chunk; 116596fd7ce5SGreg Kroah-Hartman } 116696fd7ce5SGreg Kroah-Hartman 116796fd7ce5SGreg Kroah-Hartman /* Do the write .. */ 116896fd7ce5SGreg Kroah-Hartman for (;;) { 116996fd7ce5SGreg Kroah-Hartman size_t size = count; 117096fd7ce5SGreg Kroah-Hartman if (size > chunk) 117196fd7ce5SGreg Kroah-Hartman size = chunk; 117296fd7ce5SGreg Kroah-Hartman ret = -EFAULT; 117396fd7ce5SGreg Kroah-Hartman if (copy_from_user(tty->write_buf, buf, size)) 117496fd7ce5SGreg Kroah-Hartman break; 117596fd7ce5SGreg Kroah-Hartman ret = write(tty, file, tty->write_buf, size); 117696fd7ce5SGreg Kroah-Hartman if (ret <= 0) 117796fd7ce5SGreg Kroah-Hartman break; 117896fd7ce5SGreg Kroah-Hartman written += ret; 117996fd7ce5SGreg Kroah-Hartman buf += ret; 118096fd7ce5SGreg Kroah-Hartman count -= ret; 118196fd7ce5SGreg Kroah-Hartman if (!count) 118296fd7ce5SGreg Kroah-Hartman break; 118396fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 118496fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 118596fd7ce5SGreg Kroah-Hartman break; 118696fd7ce5SGreg Kroah-Hartman cond_resched(); 118796fd7ce5SGreg Kroah-Hartman } 118837b7f3c7SJiri Slaby if (written) { 118937b7f3c7SJiri Slaby tty_update_time(&file_inode(file)->i_mtime); 119096fd7ce5SGreg Kroah-Hartman ret = written; 119137b7f3c7SJiri Slaby } 119296fd7ce5SGreg Kroah-Hartman out: 119396fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 119496fd7ce5SGreg Kroah-Hartman return ret; 119596fd7ce5SGreg Kroah-Hartman } 119696fd7ce5SGreg Kroah-Hartman 119796fd7ce5SGreg Kroah-Hartman /** 119896fd7ce5SGreg Kroah-Hartman * tty_write_message - write a message to a certain tty, not just the console. 119996fd7ce5SGreg Kroah-Hartman * @tty: the destination tty_struct 120096fd7ce5SGreg Kroah-Hartman * @msg: the message to write 120196fd7ce5SGreg Kroah-Hartman * 120296fd7ce5SGreg Kroah-Hartman * This is used for messages that need to be redirected to a specific tty. 120396fd7ce5SGreg Kroah-Hartman * We don't put it into the syslog queue right now maybe in the future if 120496fd7ce5SGreg Kroah-Hartman * really needed. 120596fd7ce5SGreg Kroah-Hartman * 120696fd7ce5SGreg Kroah-Hartman * We must still hold the BTM and test the CLOSING flag for the moment. 120796fd7ce5SGreg Kroah-Hartman */ 120896fd7ce5SGreg Kroah-Hartman 120996fd7ce5SGreg Kroah-Hartman void tty_write_message(struct tty_struct *tty, char *msg) 121096fd7ce5SGreg Kroah-Hartman { 121196fd7ce5SGreg Kroah-Hartman if (tty) { 121296fd7ce5SGreg Kroah-Hartman mutex_lock(&tty->atomic_write_lock); 121389c8d91eSAlan Cox tty_lock(tty); 12144b41b953SPeter Hurley if (tty->ops->write && tty->count > 0) 121596fd7ce5SGreg Kroah-Hartman tty->ops->write(tty, msg, strlen(msg)); 121689c8d91eSAlan Cox tty_unlock(tty); 121796fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 121896fd7ce5SGreg Kroah-Hartman } 121996fd7ce5SGreg Kroah-Hartman return; 122096fd7ce5SGreg Kroah-Hartman } 122196fd7ce5SGreg Kroah-Hartman 122296fd7ce5SGreg Kroah-Hartman 122396fd7ce5SGreg Kroah-Hartman /** 122496fd7ce5SGreg Kroah-Hartman * tty_write - write method for tty device file 122596fd7ce5SGreg Kroah-Hartman * @file: tty file pointer 122696fd7ce5SGreg Kroah-Hartman * @buf: user data to write 122796fd7ce5SGreg Kroah-Hartman * @count: bytes to write 122896fd7ce5SGreg Kroah-Hartman * @ppos: unused 122996fd7ce5SGreg Kroah-Hartman * 123096fd7ce5SGreg Kroah-Hartman * Write data to a tty device via the line discipline. 123196fd7ce5SGreg Kroah-Hartman * 123296fd7ce5SGreg Kroah-Hartman * Locking: 123396fd7ce5SGreg Kroah-Hartman * Locks the line discipline as required 123496fd7ce5SGreg Kroah-Hartman * Writes to the tty driver are serialized by the atomic_write_lock 123596fd7ce5SGreg Kroah-Hartman * and are then processed in chunks to the device. The line discipline 123696fd7ce5SGreg Kroah-Hartman * write method will not be invoked in parallel for each device. 123796fd7ce5SGreg Kroah-Hartman */ 123896fd7ce5SGreg Kroah-Hartman 123996fd7ce5SGreg Kroah-Hartman static ssize_t tty_write(struct file *file, const char __user *buf, 124096fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 124196fd7ce5SGreg Kroah-Hartman { 124296fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 124396fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 124496fd7ce5SGreg Kroah-Hartman ssize_t ret; 124596fd7ce5SGreg Kroah-Hartman 12466131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_write")) 124796fd7ce5SGreg Kroah-Hartman return -EIO; 124818900ca6SPeter Hurley if (!tty || !tty->ops->write || tty_io_error(tty)) 124996fd7ce5SGreg Kroah-Hartman return -EIO; 125096fd7ce5SGreg Kroah-Hartman /* Short term debug to catch buggy drivers */ 125196fd7ce5SGreg Kroah-Hartman if (tty->ops->write_room == NULL) 1252339f36baSPeter Hurley tty_err(tty, "missing write_room method\n"); 125396fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 1254e55afd11SPeter Hurley if (!ld) 1255e55afd11SPeter Hurley return hung_up_tty_write(file, buf, count, ppos); 125696fd7ce5SGreg Kroah-Hartman if (!ld->ops->write) 125796fd7ce5SGreg Kroah-Hartman ret = -EIO; 125896fd7ce5SGreg Kroah-Hartman else 125996fd7ce5SGreg Kroah-Hartman ret = do_tty_write(ld->ops->write, tty, file, buf, count); 126096fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 126196fd7ce5SGreg Kroah-Hartman return ret; 126296fd7ce5SGreg Kroah-Hartman } 126396fd7ce5SGreg Kroah-Hartman 126496fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *file, const char __user *buf, 126596fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 126696fd7ce5SGreg Kroah-Hartman { 126796fd7ce5SGreg Kroah-Hartman struct file *p = NULL; 126896fd7ce5SGreg Kroah-Hartman 126996fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 1270cb0942b8SAl Viro if (redirect) 1271cb0942b8SAl Viro p = get_file(redirect); 127296fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 127396fd7ce5SGreg Kroah-Hartman 127496fd7ce5SGreg Kroah-Hartman if (p) { 127596fd7ce5SGreg Kroah-Hartman ssize_t res; 127696fd7ce5SGreg Kroah-Hartman res = vfs_write(p, buf, count, &p->f_pos); 127796fd7ce5SGreg Kroah-Hartman fput(p); 127896fd7ce5SGreg Kroah-Hartman return res; 127996fd7ce5SGreg Kroah-Hartman } 128096fd7ce5SGreg Kroah-Hartman return tty_write(file, buf, count, ppos); 128196fd7ce5SGreg Kroah-Hartman } 128296fd7ce5SGreg Kroah-Hartman 1283136d5258SPeter Hurley /** 1284136d5258SPeter Hurley * tty_send_xchar - send priority character 1285136d5258SPeter Hurley * 1286136d5258SPeter Hurley * Send a high priority character to the tty even if stopped 1287136d5258SPeter Hurley * 1288136d5258SPeter Hurley * Locking: none for xchar method, write ordering for write method. 1289136d5258SPeter Hurley */ 1290136d5258SPeter Hurley 1291136d5258SPeter Hurley int tty_send_xchar(struct tty_struct *tty, char ch) 1292136d5258SPeter Hurley { 1293136d5258SPeter Hurley int was_stopped = tty->stopped; 1294136d5258SPeter Hurley 1295136d5258SPeter Hurley if (tty->ops->send_xchar) { 1296ee0c1a65SPeter Hurley down_read(&tty->termios_rwsem); 1297136d5258SPeter Hurley tty->ops->send_xchar(tty, ch); 1298ee0c1a65SPeter Hurley up_read(&tty->termios_rwsem); 1299136d5258SPeter Hurley return 0; 1300136d5258SPeter Hurley } 1301136d5258SPeter Hurley 1302136d5258SPeter Hurley if (tty_write_lock(tty, 0) < 0) 1303136d5258SPeter Hurley return -ERESTARTSYS; 1304136d5258SPeter Hurley 1305ee0c1a65SPeter Hurley down_read(&tty->termios_rwsem); 1306136d5258SPeter Hurley if (was_stopped) 1307136d5258SPeter Hurley start_tty(tty); 1308136d5258SPeter Hurley tty->ops->write(tty, &ch, 1); 1309136d5258SPeter Hurley if (was_stopped) 1310136d5258SPeter Hurley stop_tty(tty); 1311ee0c1a65SPeter Hurley up_read(&tty->termios_rwsem); 1312136d5258SPeter Hurley tty_write_unlock(tty); 1313136d5258SPeter Hurley return 0; 1314136d5258SPeter Hurley } 1315136d5258SPeter Hurley 131696fd7ce5SGreg Kroah-Hartman static char ptychar[] = "pqrstuvwxyzabcde"; 131796fd7ce5SGreg Kroah-Hartman 131896fd7ce5SGreg Kroah-Hartman /** 131996fd7ce5SGreg Kroah-Hartman * pty_line_name - generate name for a pty 132096fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 132196fd7ce5SGreg Kroah-Hartman * @index: the minor number 132296fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 6 bytes 132396fd7ce5SGreg Kroah-Hartman * 132496fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 132596fd7ce5SGreg Kroah-Hartman * buffer. 132696fd7ce5SGreg Kroah-Hartman * 132796fd7ce5SGreg Kroah-Hartman * Locking: None 132896fd7ce5SGreg Kroah-Hartman */ 132996fd7ce5SGreg Kroah-Hartman static void pty_line_name(struct tty_driver *driver, int index, char *p) 133096fd7ce5SGreg Kroah-Hartman { 133196fd7ce5SGreg Kroah-Hartman int i = index + driver->name_base; 133296fd7ce5SGreg Kroah-Hartman /* ->name is initialized to "ttyp", but "tty" is expected */ 133396fd7ce5SGreg Kroah-Hartman sprintf(p, "%s%c%x", 133496fd7ce5SGreg Kroah-Hartman driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, 133596fd7ce5SGreg Kroah-Hartman ptychar[i >> 4 & 0xf], i & 0xf); 133696fd7ce5SGreg Kroah-Hartman } 133796fd7ce5SGreg Kroah-Hartman 133896fd7ce5SGreg Kroah-Hartman /** 133996fd7ce5SGreg Kroah-Hartman * tty_line_name - generate name for a tty 134096fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 134196fd7ce5SGreg Kroah-Hartman * @index: the minor number 134296fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 7 bytes 134396fd7ce5SGreg Kroah-Hartman * 134496fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 13455c0a2450SGreg Kroah-Hartman * buffer. 134696fd7ce5SGreg Kroah-Hartman * 134796fd7ce5SGreg Kroah-Hartman * Locking: None 134896fd7ce5SGreg Kroah-Hartman */ 1349723abd87SHannes Reinecke static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p) 135096fd7ce5SGreg Kroah-Hartman { 13510019b408SJiri Slaby if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE) 1352723abd87SHannes Reinecke return sprintf(p, "%s", driver->name); 13530019b408SJiri Slaby else 1354723abd87SHannes Reinecke return sprintf(p, "%s%d", driver->name, 1355723abd87SHannes Reinecke index + driver->name_base); 135696fd7ce5SGreg Kroah-Hartman } 135796fd7ce5SGreg Kroah-Hartman 135896fd7ce5SGreg Kroah-Hartman /** 135996fd7ce5SGreg Kroah-Hartman * tty_driver_lookup_tty() - find an existing tty, if any 136096fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 136196fd7ce5SGreg Kroah-Hartman * @idx: the minor number 136296fd7ce5SGreg Kroah-Hartman * 1363aa3cb814SPeter Hurley * Return the tty, if found. If not found, return NULL or ERR_PTR() if the 1364aa3cb814SPeter Hurley * driver lookup() method returns an error. 136596fd7ce5SGreg Kroah-Hartman * 1366aa3cb814SPeter Hurley * Locking: tty_mutex must be held. If the tty is found, bump the tty kref. 136796fd7ce5SGreg Kroah-Hartman */ 136896fd7ce5SGreg Kroah-Hartman static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, 136996fd7ce5SGreg Kroah-Hartman struct inode *inode, int idx) 137096fd7ce5SGreg Kroah-Hartman { 1371aa3cb814SPeter Hurley struct tty_struct *tty; 137296fd7ce5SGreg Kroah-Hartman 1373aa3cb814SPeter Hurley if (driver->ops->lookup) 1374aa3cb814SPeter Hurley tty = driver->ops->lookup(driver, inode, idx); 1375aa3cb814SPeter Hurley else 1376aa3cb814SPeter Hurley tty = driver->ttys[idx]; 1377aa3cb814SPeter Hurley 1378aa3cb814SPeter Hurley if (!IS_ERR(tty)) 1379aa3cb814SPeter Hurley tty_kref_get(tty); 1380aa3cb814SPeter Hurley return tty; 138196fd7ce5SGreg Kroah-Hartman } 138296fd7ce5SGreg Kroah-Hartman 138396fd7ce5SGreg Kroah-Hartman /** 138496fd7ce5SGreg Kroah-Hartman * tty_init_termios - helper for termios setup 138596fd7ce5SGreg Kroah-Hartman * @tty: the tty to set up 138696fd7ce5SGreg Kroah-Hartman * 138796fd7ce5SGreg Kroah-Hartman * Initialise the termios structures for this tty. Thus runs under 138896fd7ce5SGreg Kroah-Hartman * the tty_mutex currently so we can be relaxed about ordering. 138996fd7ce5SGreg Kroah-Hartman */ 139096fd7ce5SGreg Kroah-Hartman 1391a3123fd0SPeter Hurley void tty_init_termios(struct tty_struct *tty) 139296fd7ce5SGreg Kroah-Hartman { 139396fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 139496fd7ce5SGreg Kroah-Hartman int idx = tty->index; 139596fd7ce5SGreg Kroah-Hartman 139636b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 139736b3c070SAlan Cox tty->termios = tty->driver->init_termios; 139836b3c070SAlan Cox else { 139936b3c070SAlan Cox /* Check for lazy saved data */ 140096fd7ce5SGreg Kroah-Hartman tp = tty->driver->termios[idx]; 1401ece53405SPeter Hurley if (tp != NULL) { 1402adc8d746SAlan Cox tty->termios = *tp; 1403ece53405SPeter Hurley tty->termios.c_line = tty->driver->init_termios.c_line; 1404ece53405SPeter Hurley } else 140536b3c070SAlan Cox tty->termios = tty->driver->init_termios; 140636b3c070SAlan Cox } 140796fd7ce5SGreg Kroah-Hartman /* Compatibility until drivers always set this */ 1408adc8d746SAlan Cox tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios); 1409adc8d746SAlan Cox tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios); 141096fd7ce5SGreg Kroah-Hartman } 141196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_init_termios); 141296fd7ce5SGreg Kroah-Hartman 141366d450e8SJiri Slaby int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty) 141466d450e8SJiri Slaby { 1415a3123fd0SPeter Hurley tty_init_termios(tty); 141666d450e8SJiri Slaby tty_driver_kref_get(driver); 141766d450e8SJiri Slaby tty->count++; 141866d450e8SJiri Slaby driver->ttys[tty->index] = tty; 141966d450e8SJiri Slaby return 0; 142066d450e8SJiri Slaby } 142166d450e8SJiri Slaby EXPORT_SYMBOL_GPL(tty_standard_install); 142266d450e8SJiri Slaby 142396fd7ce5SGreg Kroah-Hartman /** 142496fd7ce5SGreg Kroah-Hartman * tty_driver_install_tty() - install a tty entry in the driver 142596fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 142696fd7ce5SGreg Kroah-Hartman * @tty: the tty 142796fd7ce5SGreg Kroah-Hartman * 142896fd7ce5SGreg Kroah-Hartman * Install a tty object into the driver tables. The tty->index field 142996fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. This method is responsible 143096fd7ce5SGreg Kroah-Hartman * for ensuring any need additional structures are allocated and 143196fd7ce5SGreg Kroah-Hartman * configured. 143296fd7ce5SGreg Kroah-Hartman * 143396fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 143496fd7ce5SGreg Kroah-Hartman */ 143596fd7ce5SGreg Kroah-Hartman static int tty_driver_install_tty(struct tty_driver *driver, 143696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty) 143796fd7ce5SGreg Kroah-Hartman { 143866d450e8SJiri Slaby return driver->ops->install ? driver->ops->install(driver, tty) : 143966d450e8SJiri Slaby tty_standard_install(driver, tty); 144096fd7ce5SGreg Kroah-Hartman } 144196fd7ce5SGreg Kroah-Hartman 144296fd7ce5SGreg Kroah-Hartman /** 144396fd7ce5SGreg Kroah-Hartman * tty_driver_remove_tty() - remove a tty from the driver tables 144496fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 144596fd7ce5SGreg Kroah-Hartman * @idx: the minor number 144696fd7ce5SGreg Kroah-Hartman * 144796fd7ce5SGreg Kroah-Hartman * Remvoe a tty object from the driver tables. The tty->index field 144896fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. 144996fd7ce5SGreg Kroah-Hartman * 145096fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 145196fd7ce5SGreg Kroah-Hartman */ 145205de87edSPeter Hurley static void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty) 145396fd7ce5SGreg Kroah-Hartman { 145496fd7ce5SGreg Kroah-Hartman if (driver->ops->remove) 145596fd7ce5SGreg Kroah-Hartman driver->ops->remove(driver, tty); 145696fd7ce5SGreg Kroah-Hartman else 145796fd7ce5SGreg Kroah-Hartman driver->ttys[tty->index] = NULL; 145896fd7ce5SGreg Kroah-Hartman } 145996fd7ce5SGreg Kroah-Hartman 146096fd7ce5SGreg Kroah-Hartman /* 146196fd7ce5SGreg Kroah-Hartman * tty_reopen() - fast re-open of an open tty 146296fd7ce5SGreg Kroah-Hartman * @tty - the tty to open 146396fd7ce5SGreg Kroah-Hartman * 146496fd7ce5SGreg Kroah-Hartman * Return 0 on success, -errno on error. 14655d93e748SPeter Hurley * Re-opens on master ptys are not allowed and return -EIO. 146696fd7ce5SGreg Kroah-Hartman * 14675d93e748SPeter Hurley * Locking: Caller must hold tty_lock 146896fd7ce5SGreg Kroah-Hartman */ 146996fd7ce5SGreg Kroah-Hartman static int tty_reopen(struct tty_struct *tty) 147096fd7ce5SGreg Kroah-Hartman { 147196fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 147296fd7ce5SGreg Kroah-Hartman 147396fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY && 14745d93e748SPeter Hurley driver->subtype == PTY_TYPE_MASTER) 147596fd7ce5SGreg Kroah-Hartman return -EIO; 147696fd7ce5SGreg Kroah-Hartman 14777f22f6c9SPeter Hurley if (!tty->count) 14787f22f6c9SPeter Hurley return -EAGAIN; 14797f22f6c9SPeter Hurley 148086f2c00fSPeter Hurley if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN)) 148186f2c00fSPeter Hurley return -EBUSY; 148286f2c00fSPeter Hurley 148396fd7ce5SGreg Kroah-Hartman tty->count++; 148496fd7ce5SGreg Kroah-Hartman 1485892d1fa7SPeter Hurley if (!tty->ldisc) 1486892d1fa7SPeter Hurley return tty_ldisc_reinit(tty, tty->termios.c_line); 148796fd7ce5SGreg Kroah-Hartman 148896fd7ce5SGreg Kroah-Hartman return 0; 148996fd7ce5SGreg Kroah-Hartman } 149096fd7ce5SGreg Kroah-Hartman 149196fd7ce5SGreg Kroah-Hartman /** 149296fd7ce5SGreg Kroah-Hartman * tty_init_dev - initialise a tty device 149396fd7ce5SGreg Kroah-Hartman * @driver: tty driver we are opening a device on 149496fd7ce5SGreg Kroah-Hartman * @idx: device index 149596fd7ce5SGreg Kroah-Hartman * @ret_tty: returned tty structure 149696fd7ce5SGreg Kroah-Hartman * 149796fd7ce5SGreg Kroah-Hartman * Prepare a tty device. This may not be a "new" clean device but 149896fd7ce5SGreg Kroah-Hartman * could also be an active device. The pty drivers require special 149996fd7ce5SGreg Kroah-Hartman * handling because of this. 150096fd7ce5SGreg Kroah-Hartman * 150196fd7ce5SGreg Kroah-Hartman * Locking: 150296fd7ce5SGreg Kroah-Hartman * The function is called under the tty_mutex, which 150396fd7ce5SGreg Kroah-Hartman * protects us from the tty struct or driver itself going away. 150496fd7ce5SGreg Kroah-Hartman * 150596fd7ce5SGreg Kroah-Hartman * On exit the tty device has the line discipline attached and 150696fd7ce5SGreg Kroah-Hartman * a reference count of 1. If a pair was created for pty/tty use 150796fd7ce5SGreg Kroah-Hartman * and the other was a pty master then it too has a reference count of 1. 150896fd7ce5SGreg Kroah-Hartman * 150996fd7ce5SGreg Kroah-Hartman * WSH 06/09/97: Rewritten to remove races and properly clean up after a 151096fd7ce5SGreg Kroah-Hartman * failed open. The new code protects the open with a mutex, so it's 151196fd7ce5SGreg Kroah-Hartman * really quite straightforward. The mutex locking can probably be 151296fd7ce5SGreg Kroah-Hartman * relaxed for the (most common) case of reopening a tty. 151396fd7ce5SGreg Kroah-Hartman */ 151496fd7ce5SGreg Kroah-Hartman 1515593a27c4SKonstantin Khlebnikov struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) 151696fd7ce5SGreg Kroah-Hartman { 151796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 151896fd7ce5SGreg Kroah-Hartman int retval; 151996fd7ce5SGreg Kroah-Hartman 152096fd7ce5SGreg Kroah-Hartman /* 152196fd7ce5SGreg Kroah-Hartman * First time open is complex, especially for PTY devices. 152296fd7ce5SGreg Kroah-Hartman * This code guarantees that either everything succeeds and the 152396fd7ce5SGreg Kroah-Hartman * TTY is ready for operation, or else the table slots are vacated 152496fd7ce5SGreg Kroah-Hartman * and the allocated memory released. (Except that the termios 152596fd7ce5SGreg Kroah-Hartman * and locked termios may be retained.) 152696fd7ce5SGreg Kroah-Hartman */ 152796fd7ce5SGreg Kroah-Hartman 152896fd7ce5SGreg Kroah-Hartman if (!try_module_get(driver->owner)) 152996fd7ce5SGreg Kroah-Hartman return ERR_PTR(-ENODEV); 153096fd7ce5SGreg Kroah-Hartman 15312c964a2fSRasmus Villemoes tty = alloc_tty_struct(driver, idx); 1532d5543503SJiri Slaby if (!tty) { 1533d5543503SJiri Slaby retval = -ENOMEM; 1534d5543503SJiri Slaby goto err_module_put; 1535d5543503SJiri Slaby } 153696fd7ce5SGreg Kroah-Hartman 153789c8d91eSAlan Cox tty_lock(tty); 153896fd7ce5SGreg Kroah-Hartman retval = tty_driver_install_tty(driver, tty); 1539d5543503SJiri Slaby if (retval < 0) 1540c8b710b3SPeter Hurley goto err_free_tty; 154196fd7ce5SGreg Kroah-Hartman 154204831dc1SJiri Slaby if (!tty->port) 154304831dc1SJiri Slaby tty->port = driver->ports[idx]; 154404831dc1SJiri Slaby 15455d4121c0SJiri Slaby WARN_RATELIMIT(!tty->port, 15465d4121c0SJiri Slaby "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", 15475d4121c0SJiri Slaby __func__, tty->driver->name); 15485d4121c0SJiri Slaby 1549967fab69SJiri Slaby tty->port->itty = tty; 1550967fab69SJiri Slaby 155196fd7ce5SGreg Kroah-Hartman /* 155296fd7ce5SGreg Kroah-Hartman * Structures all installed ... call the ldisc open routines. 155396fd7ce5SGreg Kroah-Hartman * If we fail here just call release_tty to clean up. No need 155496fd7ce5SGreg Kroah-Hartman * to decrement the use counts, as release_tty doesn't care. 155596fd7ce5SGreg Kroah-Hartman */ 155696fd7ce5SGreg Kroah-Hartman retval = tty_ldisc_setup(tty, tty->link); 155796fd7ce5SGreg Kroah-Hartman if (retval) 1558d5543503SJiri Slaby goto err_release_tty; 155989c8d91eSAlan Cox /* Return the tty locked so that it cannot vanish under the caller */ 156096fd7ce5SGreg Kroah-Hartman return tty; 156196fd7ce5SGreg Kroah-Hartman 1562c8b710b3SPeter Hurley err_free_tty: 156389c8d91eSAlan Cox tty_unlock(tty); 1564d5543503SJiri Slaby free_tty_struct(tty); 1565d5543503SJiri Slaby err_module_put: 156696fd7ce5SGreg Kroah-Hartman module_put(driver->owner); 1567d5543503SJiri Slaby return ERR_PTR(retval); 156896fd7ce5SGreg Kroah-Hartman 156996fd7ce5SGreg Kroah-Hartman /* call the tty release_tty routine to clean out this slot */ 1570d5543503SJiri Slaby err_release_tty: 157189c8d91eSAlan Cox tty_unlock(tty); 1572339f36baSPeter Hurley tty_info_ratelimited(tty, "ldisc open failed (%d), clearing slot %d\n", 1573339f36baSPeter Hurley retval, idx); 157496fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 157596fd7ce5SGreg Kroah-Hartman return ERR_PTR(retval); 157696fd7ce5SGreg Kroah-Hartman } 157796fd7ce5SGreg Kroah-Hartman 1578a3123fd0SPeter Hurley static void tty_free_termios(struct tty_struct *tty) 157996fd7ce5SGreg Kroah-Hartman { 158096fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 158196fd7ce5SGreg Kroah-Hartman int idx = tty->index; 158236b3c070SAlan Cox 158336b3c070SAlan Cox /* If the port is going to reset then it has no termios to save */ 158436b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 158536b3c070SAlan Cox return; 158636b3c070SAlan Cox 158736b3c070SAlan Cox /* Stash the termios data */ 1588adc8d746SAlan Cox tp = tty->driver->termios[idx]; 158936b3c070SAlan Cox if (tp == NULL) { 159036b3c070SAlan Cox tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL); 159125080652SPeter Hurley if (tp == NULL) 159236b3c070SAlan Cox return; 15934ac5d705SDan Carpenter tty->driver->termios[idx] = tp; 159436b3c070SAlan Cox } 159536b3c070SAlan Cox *tp = tty->termios; 159696fd7ce5SGreg Kroah-Hartman } 159796fd7ce5SGreg Kroah-Hartman 1598a2965b7bSPeter Hurley /** 1599949aa64fSPeter Hurley * tty_flush_works - flush all works of a tty/pty pair 1600949aa64fSPeter Hurley * @tty: tty device to flush works for (or either end of a pty pair) 1601a2965b7bSPeter Hurley * 1602949aa64fSPeter Hurley * Sync flush all works belonging to @tty (and the 'other' tty). 1603a2965b7bSPeter Hurley */ 1604a2965b7bSPeter Hurley static void tty_flush_works(struct tty_struct *tty) 1605a2965b7bSPeter Hurley { 1606a2965b7bSPeter Hurley flush_work(&tty->SAK_work); 1607a2965b7bSPeter Hurley flush_work(&tty->hangup_work); 1608949aa64fSPeter Hurley if (tty->link) { 1609949aa64fSPeter Hurley flush_work(&tty->link->SAK_work); 1610949aa64fSPeter Hurley flush_work(&tty->link->hangup_work); 1611949aa64fSPeter Hurley } 1612a2965b7bSPeter Hurley } 161396fd7ce5SGreg Kroah-Hartman 161496fd7ce5SGreg Kroah-Hartman /** 161596fd7ce5SGreg Kroah-Hartman * release_one_tty - release tty structure memory 161696fd7ce5SGreg Kroah-Hartman * @kref: kref of tty we are obliterating 161796fd7ce5SGreg Kroah-Hartman * 161896fd7ce5SGreg Kroah-Hartman * Releases memory associated with a tty structure, and clears out the 161996fd7ce5SGreg Kroah-Hartman * driver table slots. This function is called when a device is no longer 162096fd7ce5SGreg Kroah-Hartman * in use. It also gets called when setup of a device fails. 162196fd7ce5SGreg Kroah-Hartman * 162296fd7ce5SGreg Kroah-Hartman * Locking: 162396fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 162496fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 162596fd7ce5SGreg Kroah-Hartman * 162696fd7ce5SGreg Kroah-Hartman * This method gets called from a work queue so that the driver private 162796fd7ce5SGreg Kroah-Hartman * cleanup ops can sleep (needed for USB at least) 162896fd7ce5SGreg Kroah-Hartman */ 162996fd7ce5SGreg Kroah-Hartman static void release_one_tty(struct work_struct *work) 163096fd7ce5SGreg Kroah-Hartman { 163196fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 163296fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 163396fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 1634b216df53SCyrill Gorcunov struct module *owner = driver->owner; 163596fd7ce5SGreg Kroah-Hartman 163696fd7ce5SGreg Kroah-Hartman if (tty->ops->cleanup) 163796fd7ce5SGreg Kroah-Hartman tty->ops->cleanup(tty); 163896fd7ce5SGreg Kroah-Hartman 163996fd7ce5SGreg Kroah-Hartman tty->magic = 0; 164096fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(driver); 1641b216df53SCyrill Gorcunov module_put(owner); 164296fd7ce5SGreg Kroah-Hartman 16434a510969SPeter Hurley spin_lock(&tty->files_lock); 164496fd7ce5SGreg Kroah-Hartman list_del_init(&tty->tty_files); 16454a510969SPeter Hurley spin_unlock(&tty->files_lock); 164696fd7ce5SGreg Kroah-Hartman 164796fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 164896fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 164996fd7ce5SGreg Kroah-Hartman free_tty_struct(tty); 165096fd7ce5SGreg Kroah-Hartman } 165196fd7ce5SGreg Kroah-Hartman 165296fd7ce5SGreg Kroah-Hartman static void queue_release_one_tty(struct kref *kref) 165396fd7ce5SGreg Kroah-Hartman { 165496fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = container_of(kref, struct tty_struct, kref); 165596fd7ce5SGreg Kroah-Hartman 165696fd7ce5SGreg Kroah-Hartman /* The hangup queue is now free so we can reuse it rather than 165796fd7ce5SGreg Kroah-Hartman waste a chunk of memory for each port */ 165896fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, release_one_tty); 165996fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 166096fd7ce5SGreg Kroah-Hartman } 166196fd7ce5SGreg Kroah-Hartman 166296fd7ce5SGreg Kroah-Hartman /** 166396fd7ce5SGreg Kroah-Hartman * tty_kref_put - release a tty kref 166496fd7ce5SGreg Kroah-Hartman * @tty: tty device 166596fd7ce5SGreg Kroah-Hartman * 166696fd7ce5SGreg Kroah-Hartman * Release a reference to a tty device and if need be let the kref 166796fd7ce5SGreg Kroah-Hartman * layer destruct the object for us 166896fd7ce5SGreg Kroah-Hartman */ 166996fd7ce5SGreg Kroah-Hartman 167096fd7ce5SGreg Kroah-Hartman void tty_kref_put(struct tty_struct *tty) 167196fd7ce5SGreg Kroah-Hartman { 167296fd7ce5SGreg Kroah-Hartman if (tty) 167396fd7ce5SGreg Kroah-Hartman kref_put(&tty->kref, queue_release_one_tty); 167496fd7ce5SGreg Kroah-Hartman } 167596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_kref_put); 167696fd7ce5SGreg Kroah-Hartman 167796fd7ce5SGreg Kroah-Hartman /** 167896fd7ce5SGreg Kroah-Hartman * release_tty - release tty structure memory 167996fd7ce5SGreg Kroah-Hartman * 168096fd7ce5SGreg Kroah-Hartman * Release both @tty and a possible linked partner (think pty pair), 168196fd7ce5SGreg Kroah-Hartman * and decrement the refcount of the backing module. 168296fd7ce5SGreg Kroah-Hartman * 168396fd7ce5SGreg Kroah-Hartman * Locking: 1684d155255aSAlan Cox * tty_mutex 168596fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 168696fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 168796fd7ce5SGreg Kroah-Hartman * 168896fd7ce5SGreg Kroah-Hartman */ 168996fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx) 169096fd7ce5SGreg Kroah-Hartman { 169196fd7ce5SGreg Kroah-Hartman /* This should always be true but check for the moment */ 169296fd7ce5SGreg Kroah-Hartman WARN_ON(tty->index != idx); 1693d155255aSAlan Cox WARN_ON(!mutex_is_locked(&tty_mutex)); 169436b3c070SAlan Cox if (tty->ops->shutdown) 169536b3c070SAlan Cox tty->ops->shutdown(tty); 169636b3c070SAlan Cox tty_free_termios(tty); 169736b3c070SAlan Cox tty_driver_remove_tty(tty->driver, tty); 1698967fab69SJiri Slaby tty->port->itty = NULL; 169964e377dcSPeter Hurley if (tty->link) 170064e377dcSPeter Hurley tty->link->port->itty = NULL; 1701e176058fSPeter Hurley tty_buffer_cancel_work(tty->port); 170236b3c070SAlan Cox 170396fd7ce5SGreg Kroah-Hartman tty_kref_put(tty->link); 170496fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 170596fd7ce5SGreg Kroah-Hartman } 170696fd7ce5SGreg Kroah-Hartman 170796fd7ce5SGreg Kroah-Hartman /** 1708955787caSJiri Slaby * tty_release_checks - check a tty before real release 1709955787caSJiri Slaby * @tty: tty to check 1710955787caSJiri Slaby * @o_tty: link of @tty (if any) 1711955787caSJiri Slaby * @idx: index of the tty 1712955787caSJiri Slaby * 1713955787caSJiri Slaby * Performs some paranoid checking before true release of the @tty. 1714955787caSJiri Slaby * This is a no-op unless TTY_PARANOIA_CHECK is defined. 1715955787caSJiri Slaby */ 1716359b9fb5SPeter Hurley static int tty_release_checks(struct tty_struct *tty, int idx) 1717955787caSJiri Slaby { 1718955787caSJiri Slaby #ifdef TTY_PARANOIA_CHECK 1719955787caSJiri Slaby if (idx < 0 || idx >= tty->driver->num) { 1720e2dfa3d3SPeter Hurley tty_debug(tty, "bad idx %d\n", idx); 1721955787caSJiri Slaby return -1; 1722955787caSJiri Slaby } 1723955787caSJiri Slaby 1724955787caSJiri Slaby /* not much to check for devpts */ 1725955787caSJiri Slaby if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) 1726955787caSJiri Slaby return 0; 1727955787caSJiri Slaby 1728955787caSJiri Slaby if (tty != tty->driver->ttys[idx]) { 1729e2dfa3d3SPeter Hurley tty_debug(tty, "bad driver table[%d] = %p\n", 1730e2dfa3d3SPeter Hurley idx, tty->driver->ttys[idx]); 1731955787caSJiri Slaby return -1; 1732955787caSJiri Slaby } 1733955787caSJiri Slaby if (tty->driver->other) { 1734359b9fb5SPeter Hurley struct tty_struct *o_tty = tty->link; 1735359b9fb5SPeter Hurley 1736955787caSJiri Slaby if (o_tty != tty->driver->other->ttys[idx]) { 1737e2dfa3d3SPeter Hurley tty_debug(tty, "bad other table[%d] = %p\n", 1738e2dfa3d3SPeter Hurley idx, tty->driver->other->ttys[idx]); 1739955787caSJiri Slaby return -1; 1740955787caSJiri Slaby } 1741955787caSJiri Slaby if (o_tty->link != tty) { 1742e2dfa3d3SPeter Hurley tty_debug(tty, "bad link = %p\n", o_tty->link); 1743955787caSJiri Slaby return -1; 1744955787caSJiri Slaby } 1745955787caSJiri Slaby } 1746955787caSJiri Slaby #endif 1747955787caSJiri Slaby return 0; 1748955787caSJiri Slaby } 1749955787caSJiri Slaby 1750955787caSJiri Slaby /** 175196fd7ce5SGreg Kroah-Hartman * tty_release - vfs callback for close 175296fd7ce5SGreg Kroah-Hartman * @inode: inode of tty 175396fd7ce5SGreg Kroah-Hartman * @filp: file pointer for handle to tty 175496fd7ce5SGreg Kroah-Hartman * 175596fd7ce5SGreg Kroah-Hartman * Called the last time each file handle is closed that references 175696fd7ce5SGreg Kroah-Hartman * this tty. There may however be several such references. 175796fd7ce5SGreg Kroah-Hartman * 175896fd7ce5SGreg Kroah-Hartman * Locking: 175996fd7ce5SGreg Kroah-Hartman * Takes bkl. See tty_release_dev 176096fd7ce5SGreg Kroah-Hartman * 176196fd7ce5SGreg Kroah-Hartman * Even releasing the tty structures is a tricky business.. We have 176296fd7ce5SGreg Kroah-Hartman * to be very careful that the structures are all released at the 176396fd7ce5SGreg Kroah-Hartman * same time, as interrupts might otherwise get the wrong pointers. 176496fd7ce5SGreg Kroah-Hartman * 176596fd7ce5SGreg Kroah-Hartman * WSH 09/09/97: rewritten to avoid some nasty race conditions that could 176696fd7ce5SGreg Kroah-Hartman * lead to double frees or releasing memory still in use. 176796fd7ce5SGreg Kroah-Hartman */ 176896fd7ce5SGreg Kroah-Hartman 176996fd7ce5SGreg Kroah-Hartman int tty_release(struct inode *inode, struct file *filp) 177096fd7ce5SGreg Kroah-Hartman { 177196fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 17727ffb6da9SPeter Hurley struct tty_struct *o_tty = NULL; 17737ffb6da9SPeter Hurley int do_sleep, final; 177496fd7ce5SGreg Kroah-Hartman int idx; 177537b16457SPeter Hurley long timeout = 0; 1776494c1eacSPeter Hurley int once = 1; 177796fd7ce5SGreg Kroah-Hartman 17789de44bd6SJiri Slaby if (tty_paranoia_check(tty, inode, __func__)) 177996fd7ce5SGreg Kroah-Hartman return 0; 178096fd7ce5SGreg Kroah-Hartman 178189c8d91eSAlan Cox tty_lock(tty); 17829de44bd6SJiri Slaby check_tty_count(tty, __func__); 178396fd7ce5SGreg Kroah-Hartman 178496fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); 178596fd7ce5SGreg Kroah-Hartman 178696fd7ce5SGreg Kroah-Hartman idx = tty->index; 17877ffb6da9SPeter Hurley if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 17887ffb6da9SPeter Hurley tty->driver->subtype == PTY_TYPE_MASTER) 178996fd7ce5SGreg Kroah-Hartman o_tty = tty->link; 179096fd7ce5SGreg Kroah-Hartman 1791359b9fb5SPeter Hurley if (tty_release_checks(tty, idx)) { 179289c8d91eSAlan Cox tty_unlock(tty); 179396fd7ce5SGreg Kroah-Hartman return 0; 179496fd7ce5SGreg Kroah-Hartman } 179596fd7ce5SGreg Kroah-Hartman 1796d435cefeSPeter Hurley tty_debug_hangup(tty, "releasing (count=%d)\n", tty->count); 179796fd7ce5SGreg Kroah-Hartman 179896fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 179996fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, filp); 180096fd7ce5SGreg Kroah-Hartman 18012aff5e2bSPeter Hurley /* If tty is pty master, lock the slave pty (stable lock order) */ 18022aff5e2bSPeter Hurley tty_lock_slave(o_tty); 18032aff5e2bSPeter Hurley 180496fd7ce5SGreg Kroah-Hartman /* 180596fd7ce5SGreg Kroah-Hartman * Sanity check: if tty->count is going to zero, there shouldn't be 180696fd7ce5SGreg Kroah-Hartman * any waiters on tty->read_wait or tty->write_wait. We test the 180796fd7ce5SGreg Kroah-Hartman * wait queues and kick everyone out _before_ actually starting to 180896fd7ce5SGreg Kroah-Hartman * close. This ensures that we won't block while releasing the tty 180996fd7ce5SGreg Kroah-Hartman * structure. 181096fd7ce5SGreg Kroah-Hartman * 181196fd7ce5SGreg Kroah-Hartman * The test for the o_tty closing is necessary, since the master and 181296fd7ce5SGreg Kroah-Hartman * slave sides may close in any order. If the slave side closes out 181396fd7ce5SGreg Kroah-Hartman * first, its count will be one, since the master side holds an open. 1814324c1650SPeter Hurley * Thus this test wouldn't be triggered at the time the slave closed, 181596fd7ce5SGreg Kroah-Hartman * so we do it now. 181696fd7ce5SGreg Kroah-Hartman */ 1817d5e370a4SPeter Hurley while (1) { 181896fd7ce5SGreg Kroah-Hartman do_sleep = 0; 181996fd7ce5SGreg Kroah-Hartman 1820324c1650SPeter Hurley if (tty->count <= 1) { 182196fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->read_wait)) { 182296fd7ce5SGreg Kroah-Hartman wake_up_poll(&tty->read_wait, POLLIN); 182396fd7ce5SGreg Kroah-Hartman do_sleep++; 182496fd7ce5SGreg Kroah-Hartman } 182596fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->write_wait)) { 182696fd7ce5SGreg Kroah-Hartman wake_up_poll(&tty->write_wait, POLLOUT); 182796fd7ce5SGreg Kroah-Hartman do_sleep++; 182896fd7ce5SGreg Kroah-Hartman } 182996fd7ce5SGreg Kroah-Hartman } 18307ffb6da9SPeter Hurley if (o_tty && o_tty->count <= 1) { 183196fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->read_wait)) { 183296fd7ce5SGreg Kroah-Hartman wake_up_poll(&o_tty->read_wait, POLLIN); 183396fd7ce5SGreg Kroah-Hartman do_sleep++; 183496fd7ce5SGreg Kroah-Hartman } 183596fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->write_wait)) { 183696fd7ce5SGreg Kroah-Hartman wake_up_poll(&o_tty->write_wait, POLLOUT); 183796fd7ce5SGreg Kroah-Hartman do_sleep++; 183896fd7ce5SGreg Kroah-Hartman } 183996fd7ce5SGreg Kroah-Hartman } 184096fd7ce5SGreg Kroah-Hartman if (!do_sleep) 184196fd7ce5SGreg Kroah-Hartman break; 184296fd7ce5SGreg Kroah-Hartman 1843494c1eacSPeter Hurley if (once) { 1844494c1eacSPeter Hurley once = 0; 1845339f36baSPeter Hurley tty_warn(tty, "read/write wait queue active!\n"); 1846494c1eacSPeter Hurley } 184737b16457SPeter Hurley schedule_timeout_killable(timeout); 184837b16457SPeter Hurley if (timeout < 120 * HZ) 184937b16457SPeter Hurley timeout = 2 * timeout + 1; 185037b16457SPeter Hurley else 185137b16457SPeter Hurley timeout = MAX_SCHEDULE_TIMEOUT; 185296fd7ce5SGreg Kroah-Hartman } 185396fd7ce5SGreg Kroah-Hartman 18547ffb6da9SPeter Hurley if (o_tty) { 185596fd7ce5SGreg Kroah-Hartman if (--o_tty->count < 0) { 1856339f36baSPeter Hurley tty_warn(tty, "bad slave count (%d)\n", o_tty->count); 185796fd7ce5SGreg Kroah-Hartman o_tty->count = 0; 185896fd7ce5SGreg Kroah-Hartman } 185996fd7ce5SGreg Kroah-Hartman } 186096fd7ce5SGreg Kroah-Hartman if (--tty->count < 0) { 1861339f36baSPeter Hurley tty_warn(tty, "bad tty->count (%d)\n", tty->count); 186296fd7ce5SGreg Kroah-Hartman tty->count = 0; 186396fd7ce5SGreg Kroah-Hartman } 186496fd7ce5SGreg Kroah-Hartman 186596fd7ce5SGreg Kroah-Hartman /* 186696fd7ce5SGreg Kroah-Hartman * We've decremented tty->count, so we need to remove this file 186796fd7ce5SGreg Kroah-Hartman * descriptor off the tty->tty_files list; this serves two 186896fd7ce5SGreg Kroah-Hartman * purposes: 186996fd7ce5SGreg Kroah-Hartman * - check_tty_count sees the correct number of file descriptors 187096fd7ce5SGreg Kroah-Hartman * associated with this tty. 187196fd7ce5SGreg Kroah-Hartman * - do_tty_hangup no longer sees this file descriptor as 187296fd7ce5SGreg Kroah-Hartman * something that needs to be handled for hangups. 187396fd7ce5SGreg Kroah-Hartman */ 187496fd7ce5SGreg Kroah-Hartman tty_del_file(filp); 187596fd7ce5SGreg Kroah-Hartman 187696fd7ce5SGreg Kroah-Hartman /* 187796fd7ce5SGreg Kroah-Hartman * Perform some housekeeping before deciding whether to return. 187896fd7ce5SGreg Kroah-Hartman * 187996fd7ce5SGreg Kroah-Hartman * If _either_ side is closing, make sure there aren't any 188096fd7ce5SGreg Kroah-Hartman * processes that still think tty or o_tty is their controlling 188196fd7ce5SGreg Kroah-Hartman * tty. 188296fd7ce5SGreg Kroah-Hartman */ 1883324c1650SPeter Hurley if (!tty->count) { 188496fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 188596fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 18867ffb6da9SPeter Hurley if (o_tty) 188796fd7ce5SGreg Kroah-Hartman session_clear_tty(o_tty->session); 188896fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 188996fd7ce5SGreg Kroah-Hartman } 189096fd7ce5SGreg Kroah-Hartman 1891324c1650SPeter Hurley /* check whether both sides are closing ... */ 18927ffb6da9SPeter Hurley final = !tty->count && !(o_tty && o_tty->count); 1893324c1650SPeter Hurley 18942aff5e2bSPeter Hurley tty_unlock_slave(o_tty); 18952aff5e2bSPeter Hurley tty_unlock(tty); 18962aff5e2bSPeter Hurley 189704980706SPeter Hurley /* At this point, the tty->count == 0 should ensure a dead tty 1898d155255aSAlan Cox cannot be re-opened by a racing opener */ 189996fd7ce5SGreg Kroah-Hartman 1900324c1650SPeter Hurley if (!final) 190196fd7ce5SGreg Kroah-Hartman return 0; 190296fd7ce5SGreg Kroah-Hartman 1903accff793SPeter Hurley tty_debug_hangup(tty, "final close\n"); 190496fd7ce5SGreg Kroah-Hartman /* 190596fd7ce5SGreg Kroah-Hartman * Ask the line discipline code to release its structures 190696fd7ce5SGreg Kroah-Hartman */ 190762462aefSPeter Hurley tty_ldisc_release(tty); 1908a2965b7bSPeter Hurley 1909a2965b7bSPeter Hurley /* Wait for pending work before tty destruction commmences */ 1910a2965b7bSPeter Hurley tty_flush_works(tty); 1911a2965b7bSPeter Hurley 1912d435cefeSPeter Hurley tty_debug_hangup(tty, "freeing structure\n"); 191396fd7ce5SGreg Kroah-Hartman /* 191496fd7ce5SGreg Kroah-Hartman * The release_tty function takes care of the details of clearing 191589c8d91eSAlan Cox * the slots and preserving the termios structure. The tty_unlock_pair 191689c8d91eSAlan Cox * should be safe as we keep a kref while the tty is locked (so the 191789c8d91eSAlan Cox * unlock never unlocks a freed tty). 191896fd7ce5SGreg Kroah-Hartman */ 1919d155255aSAlan Cox mutex_lock(&tty_mutex); 192096fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 1921d155255aSAlan Cox mutex_unlock(&tty_mutex); 192296fd7ce5SGreg Kroah-Hartman 192396fd7ce5SGreg Kroah-Hartman return 0; 192496fd7ce5SGreg Kroah-Hartman } 192596fd7ce5SGreg Kroah-Hartman 192696fd7ce5SGreg Kroah-Hartman /** 192752494eebSPeter Hurley * tty_open_current_tty - get locked tty of current task 1928b82154acSJiri Slaby * @device: device number 1929b82154acSJiri Slaby * @filp: file pointer to tty 193052494eebSPeter Hurley * @return: locked tty of the current task iff @device is /dev/tty 193152494eebSPeter Hurley * 193252494eebSPeter Hurley * Performs a re-open of the current task's controlling tty. 1933b82154acSJiri Slaby * 1934b82154acSJiri Slaby * We cannot return driver and index like for the other nodes because 1935b82154acSJiri Slaby * devpts will not work then. It expects inodes to be from devpts FS. 1936b82154acSJiri Slaby */ 1937b82154acSJiri Slaby static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) 1938b82154acSJiri Slaby { 1939b82154acSJiri Slaby struct tty_struct *tty; 194052494eebSPeter Hurley int retval; 1941b82154acSJiri Slaby 1942b82154acSJiri Slaby if (device != MKDEV(TTYAUX_MAJOR, 0)) 1943b82154acSJiri Slaby return NULL; 1944b82154acSJiri Slaby 1945b82154acSJiri Slaby tty = get_current_tty(); 1946b82154acSJiri Slaby if (!tty) 1947b82154acSJiri Slaby return ERR_PTR(-ENXIO); 1948b82154acSJiri Slaby 1949b82154acSJiri Slaby filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ 1950b82154acSJiri Slaby /* noctty = 1; */ 195152494eebSPeter Hurley tty_lock(tty); 195252494eebSPeter Hurley tty_kref_put(tty); /* safe to drop the kref now */ 195352494eebSPeter Hurley 195452494eebSPeter Hurley retval = tty_reopen(tty); 195552494eebSPeter Hurley if (retval < 0) { 195652494eebSPeter Hurley tty_unlock(tty); 195752494eebSPeter Hurley tty = ERR_PTR(retval); 195852494eebSPeter Hurley } 1959b82154acSJiri Slaby return tty; 1960b82154acSJiri Slaby } 1961b82154acSJiri Slaby 1962b82154acSJiri Slaby /** 19635b5e7040SJiri Slaby * tty_lookup_driver - lookup a tty driver for a given device file 19645b5e7040SJiri Slaby * @device: device number 19655b5e7040SJiri Slaby * @filp: file pointer to tty 19665b5e7040SJiri Slaby * @noctty: set if the device should not become a controlling tty 19675b5e7040SJiri Slaby * @index: index for the device in the @return driver 19685b5e7040SJiri Slaby * @return: driver for this inode (with increased refcount) 19695b5e7040SJiri Slaby * 19705b5e7040SJiri Slaby * If @return is not erroneous, the caller is responsible to decrement the 19715b5e7040SJiri Slaby * refcount by tty_driver_kref_put. 19725b5e7040SJiri Slaby * 19735b5e7040SJiri Slaby * Locking: tty_mutex protects get_tty_driver 19745b5e7040SJiri Slaby */ 19755b5e7040SJiri Slaby static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp, 197611e1d4aaSPeter Hurley int *index) 19775b5e7040SJiri Slaby { 19785b5e7040SJiri Slaby struct tty_driver *driver; 19795b5e7040SJiri Slaby 19802cd0050cSJiri Slaby switch (device) { 19815b5e7040SJiri Slaby #ifdef CONFIG_VT 19822cd0050cSJiri Slaby case MKDEV(TTY_MAJOR, 0): { 19835b5e7040SJiri Slaby extern struct tty_driver *console_driver; 19845b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 19855b5e7040SJiri Slaby *index = fg_console; 19862cd0050cSJiri Slaby break; 19875b5e7040SJiri Slaby } 19885b5e7040SJiri Slaby #endif 19892cd0050cSJiri Slaby case MKDEV(TTYAUX_MAJOR, 1): { 19905b5e7040SJiri Slaby struct tty_driver *console_driver = console_device(index); 19915b5e7040SJiri Slaby if (console_driver) { 19925b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 19935b5e7040SJiri Slaby if (driver) { 19945b5e7040SJiri Slaby /* Don't let /dev/console block */ 19955b5e7040SJiri Slaby filp->f_flags |= O_NONBLOCK; 19962cd0050cSJiri Slaby break; 19975b5e7040SJiri Slaby } 19985b5e7040SJiri Slaby } 19995b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 20005b5e7040SJiri Slaby } 20012cd0050cSJiri Slaby default: 20025b5e7040SJiri Slaby driver = get_tty_driver(device, index); 20035b5e7040SJiri Slaby if (!driver) 20045b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 20052cd0050cSJiri Slaby break; 20062cd0050cSJiri Slaby } 20075b5e7040SJiri Slaby return driver; 20085b5e7040SJiri Slaby } 20095b5e7040SJiri Slaby 20105b5e7040SJiri Slaby /** 2011d6203d0cSPeter Hurley * tty_open_by_driver - open a tty device 2012d6203d0cSPeter Hurley * @device: dev_t of device to open 2013d6203d0cSPeter Hurley * @inode: inode of device file 2014d6203d0cSPeter Hurley * @filp: file pointer to tty 2015d6203d0cSPeter Hurley * 2016d6203d0cSPeter Hurley * Performs the driver lookup, checks for a reopen, or otherwise 2017d6203d0cSPeter Hurley * performs the first-time tty initialization. 2018d6203d0cSPeter Hurley * 2019d6203d0cSPeter Hurley * Returns the locked initialized or re-opened &tty_struct 2020d6203d0cSPeter Hurley * 2021d6203d0cSPeter Hurley * Claims the global tty_mutex to serialize: 2022d6203d0cSPeter Hurley * - concurrent first-time tty initialization 2023d6203d0cSPeter Hurley * - concurrent tty driver removal w/ lookup 2024d6203d0cSPeter Hurley * - concurrent tty removal from driver table 2025d6203d0cSPeter Hurley */ 2026d6203d0cSPeter Hurley static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode, 2027d6203d0cSPeter Hurley struct file *filp) 2028d6203d0cSPeter Hurley { 2029d6203d0cSPeter Hurley struct tty_struct *tty; 2030d6203d0cSPeter Hurley struct tty_driver *driver = NULL; 2031d6203d0cSPeter Hurley int index = -1; 2032d6203d0cSPeter Hurley int retval; 2033d6203d0cSPeter Hurley 2034d6203d0cSPeter Hurley mutex_lock(&tty_mutex); 2035d6203d0cSPeter Hurley driver = tty_lookup_driver(device, filp, &index); 2036d6203d0cSPeter Hurley if (IS_ERR(driver)) { 2037d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 2038d6203d0cSPeter Hurley return ERR_CAST(driver); 2039d6203d0cSPeter Hurley } 2040d6203d0cSPeter Hurley 2041d6203d0cSPeter Hurley /* check whether we're reopening an existing tty */ 2042d6203d0cSPeter Hurley tty = tty_driver_lookup_tty(driver, inode, index); 2043d6203d0cSPeter Hurley if (IS_ERR(tty)) { 2044d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 2045d6203d0cSPeter Hurley goto out; 2046d6203d0cSPeter Hurley } 2047d6203d0cSPeter Hurley 2048d6203d0cSPeter Hurley if (tty) { 2049d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 2050d6203d0cSPeter Hurley retval = tty_lock_interruptible(tty); 20515e00bbfbSPeter Hurley tty_kref_put(tty); /* drop kref from tty_driver_lookup_tty() */ 2052d6203d0cSPeter Hurley if (retval) { 2053d6203d0cSPeter Hurley if (retval == -EINTR) 2054d6203d0cSPeter Hurley retval = -ERESTARTSYS; 2055d6203d0cSPeter Hurley tty = ERR_PTR(retval); 2056d6203d0cSPeter Hurley goto out; 2057d6203d0cSPeter Hurley } 2058d6203d0cSPeter Hurley retval = tty_reopen(tty); 2059d6203d0cSPeter Hurley if (retval < 0) { 2060d6203d0cSPeter Hurley tty_unlock(tty); 2061d6203d0cSPeter Hurley tty = ERR_PTR(retval); 2062d6203d0cSPeter Hurley } 2063d6203d0cSPeter Hurley } else { /* Returns with the tty_lock held for now */ 2064d6203d0cSPeter Hurley tty = tty_init_dev(driver, index); 2065d6203d0cSPeter Hurley mutex_unlock(&tty_mutex); 2066d6203d0cSPeter Hurley } 2067d6203d0cSPeter Hurley out: 2068d6203d0cSPeter Hurley tty_driver_kref_put(driver); 2069d6203d0cSPeter Hurley return tty; 2070d6203d0cSPeter Hurley } 2071d6203d0cSPeter Hurley 2072d6203d0cSPeter Hurley /** 207396fd7ce5SGreg Kroah-Hartman * tty_open - open a tty device 207496fd7ce5SGreg Kroah-Hartman * @inode: inode of device file 207596fd7ce5SGreg Kroah-Hartman * @filp: file pointer to tty 207696fd7ce5SGreg Kroah-Hartman * 207796fd7ce5SGreg Kroah-Hartman * tty_open and tty_release keep up the tty count that contains the 207896fd7ce5SGreg Kroah-Hartman * number of opens done on a tty. We cannot use the inode-count, as 207996fd7ce5SGreg Kroah-Hartman * different inodes might point to the same tty. 208096fd7ce5SGreg Kroah-Hartman * 208196fd7ce5SGreg Kroah-Hartman * Open-counting is needed for pty masters, as well as for keeping 208296fd7ce5SGreg Kroah-Hartman * track of serial lines: DTR is dropped when the last close happens. 208396fd7ce5SGreg Kroah-Hartman * (This is not done solely through tty->count, now. - Ted 1/27/92) 208496fd7ce5SGreg Kroah-Hartman * 208596fd7ce5SGreg Kroah-Hartman * The termios state of a pty is reset on first open so that 208696fd7ce5SGreg Kroah-Hartman * settings don't persist across reuse. 208796fd7ce5SGreg Kroah-Hartman * 20885b5e7040SJiri Slaby * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev. 208996fd7ce5SGreg Kroah-Hartman * tty->count should protect the rest. 209096fd7ce5SGreg Kroah-Hartman * ->siglock protects ->signal/->sighand 209189c8d91eSAlan Cox * 209289c8d91eSAlan Cox * Note: the tty_unlock/lock cases without a ref are only safe due to 209389c8d91eSAlan Cox * tty_mutex 209496fd7ce5SGreg Kroah-Hartman */ 209596fd7ce5SGreg Kroah-Hartman 209696fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *inode, struct file *filp) 209796fd7ce5SGreg Kroah-Hartman { 2098b82154acSJiri Slaby struct tty_struct *tty; 209996fd7ce5SGreg Kroah-Hartman int noctty, retval; 210096fd7ce5SGreg Kroah-Hartman dev_t device = inode->i_rdev; 210196fd7ce5SGreg Kroah-Hartman unsigned saved_flags = filp->f_flags; 210296fd7ce5SGreg Kroah-Hartman 210396fd7ce5SGreg Kroah-Hartman nonseekable_open(inode, filp); 210496fd7ce5SGreg Kroah-Hartman 210596fd7ce5SGreg Kroah-Hartman retry_open: 2106fa90e1c9SJiri Slaby retval = tty_alloc_file(filp); 2107fa90e1c9SJiri Slaby if (retval) 2108fa90e1c9SJiri Slaby return -ENOMEM; 2109fa90e1c9SJiri Slaby 2110b82154acSJiri Slaby tty = tty_open_current_tty(device, filp); 2111d6203d0cSPeter Hurley if (!tty) 2112d6203d0cSPeter Hurley tty = tty_open_by_driver(device, inode, filp); 211352494eebSPeter Hurley 211496fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty)) { 2115d6203d0cSPeter Hurley tty_free_file(filp); 2116ba5db448SJiri Slaby retval = PTR_ERR(tty); 21177f22f6c9SPeter Hurley if (retval != -EAGAIN || signal_pending(current)) 2118d6203d0cSPeter Hurley return retval; 21197f22f6c9SPeter Hurley schedule(); 21207f22f6c9SPeter Hurley goto retry_open; 212196fd7ce5SGreg Kroah-Hartman } 212296fd7ce5SGreg Kroah-Hartman 2123fa90e1c9SJiri Slaby tty_add_file(tty, filp); 212496fd7ce5SGreg Kroah-Hartman 21259de44bd6SJiri Slaby check_tty_count(tty, __func__); 2126d435cefeSPeter Hurley tty_debug_hangup(tty, "opening (count=%d)\n", tty->count); 2127accff793SPeter Hurley 212896fd7ce5SGreg Kroah-Hartman if (tty->ops->open) 212996fd7ce5SGreg Kroah-Hartman retval = tty->ops->open(tty, filp); 213096fd7ce5SGreg Kroah-Hartman else 213196fd7ce5SGreg Kroah-Hartman retval = -ENODEV; 213296fd7ce5SGreg Kroah-Hartman filp->f_flags = saved_flags; 213396fd7ce5SGreg Kroah-Hartman 213496fd7ce5SGreg Kroah-Hartman if (retval) { 2135d435cefeSPeter Hurley tty_debug_hangup(tty, "open error %d, releasing\n", retval); 2136accff793SPeter Hurley 213789c8d91eSAlan Cox tty_unlock(tty); /* need to call tty_release without BTM */ 213896fd7ce5SGreg Kroah-Hartman tty_release(inode, filp); 213996fd7ce5SGreg Kroah-Hartman if (retval != -ERESTARTSYS) 214096fd7ce5SGreg Kroah-Hartman return retval; 214196fd7ce5SGreg Kroah-Hartman 214296fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 214396fd7ce5SGreg Kroah-Hartman return retval; 214496fd7ce5SGreg Kroah-Hartman 214596fd7ce5SGreg Kroah-Hartman schedule(); 214696fd7ce5SGreg Kroah-Hartman /* 214796fd7ce5SGreg Kroah-Hartman * Need to reset f_op in case a hangup happened. 214896fd7ce5SGreg Kroah-Hartman */ 21491256937fSPeter Hurley if (tty_hung_up_p(filp)) 215096fd7ce5SGreg Kroah-Hartman filp->f_op = &tty_fops; 215196fd7ce5SGreg Kroah-Hartman goto retry_open; 215296fd7ce5SGreg Kroah-Hartman } 2153d4855e1fSPeter Hurley clear_bit(TTY_HUPPED, &tty->flags); 215496fd7ce5SGreg Kroah-Hartman 215596fd7ce5SGreg Kroah-Hartman 21562c411c11SPeter Hurley read_lock(&tasklist_lock); 215796fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 215811e1d4aaSPeter Hurley noctty = (filp->f_flags & O_NOCTTY) || 2159da5a0fc6SPeter Hurley (IS_ENABLED(CONFIG_VT) && device == MKDEV(TTY_MAJOR, 0)) || 216011e1d4aaSPeter Hurley device == MKDEV(TTYAUX_MAJOR, 1) || 216111e1d4aaSPeter Hurley (tty->driver->type == TTY_DRIVER_TYPE_PTY && 216211e1d4aaSPeter Hurley tty->driver->subtype == PTY_TYPE_MASTER); 216311e1d4aaSPeter Hurley 216496fd7ce5SGreg Kroah-Hartman if (!noctty && 216596fd7ce5SGreg Kroah-Hartman current->signal->leader && 216696fd7ce5SGreg Kroah-Hartman !current->signal->tty && 21670c556271SJann Horn tty->session == NULL) { 21680c556271SJann Horn /* 21690c556271SJann Horn * Don't let a process that only has write access to the tty 21700c556271SJann Horn * obtain the privileges associated with having a tty as 21710c556271SJann Horn * controlling terminal (being able to reopen it with full 21720c556271SJann Horn * access through /dev/tty, being able to perform pushback). 21730c556271SJann Horn * Many distributions set the group of all ttys to "tty" and 21740c556271SJann Horn * grant write-only access to all terminals for setgid tty 21750c556271SJann Horn * binaries, which should not imply full privileges on all ttys. 21760c556271SJann Horn * 21770c556271SJann Horn * This could theoretically break old code that performs open() 21780c556271SJann Horn * on a write-only file descriptor. In that case, it might be 21790c556271SJann Horn * necessary to also permit this if 21800c556271SJann Horn * inode_permission(inode, MAY_READ) == 0. 21810c556271SJann Horn */ 21820c556271SJann Horn if (filp->f_mode & FMODE_READ) 2183bce65f18SPeter Hurley __proc_set_tty(tty); 21840c556271SJann Horn } 218596fd7ce5SGreg Kroah-Hartman spin_unlock_irq(¤t->sighand->siglock); 21862c411c11SPeter Hurley read_unlock(&tasklist_lock); 218789c8d91eSAlan Cox tty_unlock(tty); 218896fd7ce5SGreg Kroah-Hartman return 0; 218996fd7ce5SGreg Kroah-Hartman } 219096fd7ce5SGreg Kroah-Hartman 219196fd7ce5SGreg Kroah-Hartman 219296fd7ce5SGreg Kroah-Hartman 219396fd7ce5SGreg Kroah-Hartman /** 219496fd7ce5SGreg Kroah-Hartman * tty_poll - check tty status 219596fd7ce5SGreg Kroah-Hartman * @filp: file being polled 219696fd7ce5SGreg Kroah-Hartman * @wait: poll wait structures to update 219796fd7ce5SGreg Kroah-Hartman * 219896fd7ce5SGreg Kroah-Hartman * Call the line discipline polling method to obtain the poll 219996fd7ce5SGreg Kroah-Hartman * status of the device. 220096fd7ce5SGreg Kroah-Hartman * 220196fd7ce5SGreg Kroah-Hartman * Locking: locks called line discipline but ldisc poll method 220296fd7ce5SGreg Kroah-Hartman * may be re-entered freely by other callers. 220396fd7ce5SGreg Kroah-Hartman */ 220496fd7ce5SGreg Kroah-Hartman 220596fd7ce5SGreg Kroah-Hartman static unsigned int tty_poll(struct file *filp, poll_table *wait) 220696fd7ce5SGreg Kroah-Hartman { 220796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 220896fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 220996fd7ce5SGreg Kroah-Hartman int ret = 0; 221096fd7ce5SGreg Kroah-Hartman 22116131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_poll")) 221296fd7ce5SGreg Kroah-Hartman return 0; 221396fd7ce5SGreg Kroah-Hartman 221496fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2215e55afd11SPeter Hurley if (!ld) 2216e55afd11SPeter Hurley return hung_up_tty_poll(filp, wait); 221796fd7ce5SGreg Kroah-Hartman if (ld->ops->poll) 2218c961bfb1SPeter Hurley ret = ld->ops->poll(tty, filp, wait); 221996fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 222096fd7ce5SGreg Kroah-Hartman return ret; 222196fd7ce5SGreg Kroah-Hartman } 222296fd7ce5SGreg Kroah-Hartman 222396fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on) 222496fd7ce5SGreg Kroah-Hartman { 222596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 222696fd7ce5SGreg Kroah-Hartman unsigned long flags; 222796fd7ce5SGreg Kroah-Hartman int retval = 0; 222896fd7ce5SGreg Kroah-Hartman 22296131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_fasync")) 223096fd7ce5SGreg Kroah-Hartman goto out; 223196fd7ce5SGreg Kroah-Hartman 223296fd7ce5SGreg Kroah-Hartman retval = fasync_helper(fd, filp, on, &tty->fasync); 223396fd7ce5SGreg Kroah-Hartman if (retval <= 0) 223496fd7ce5SGreg Kroah-Hartman goto out; 223596fd7ce5SGreg Kroah-Hartman 223696fd7ce5SGreg Kroah-Hartman if (on) { 223796fd7ce5SGreg Kroah-Hartman enum pid_type type; 223896fd7ce5SGreg Kroah-Hartman struct pid *pid; 2239f6c8dbe6SPeter Hurley 224096fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 224196fd7ce5SGreg Kroah-Hartman if (tty->pgrp) { 224296fd7ce5SGreg Kroah-Hartman pid = tty->pgrp; 224396fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PGID; 224496fd7ce5SGreg Kroah-Hartman } else { 224596fd7ce5SGreg Kroah-Hartman pid = task_pid(current); 224696fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PID; 224796fd7ce5SGreg Kroah-Hartman } 224896fd7ce5SGreg Kroah-Hartman get_pid(pid); 224996fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 2250e0b93eddSJeff Layton __f_setown(filp, pid, type, 0); 225196fd7ce5SGreg Kroah-Hartman put_pid(pid); 2252e0b93eddSJeff Layton retval = 0; 225396fd7ce5SGreg Kroah-Hartman } 225496fd7ce5SGreg Kroah-Hartman out: 225596fd7ce5SGreg Kroah-Hartman return retval; 225696fd7ce5SGreg Kroah-Hartman } 225796fd7ce5SGreg Kroah-Hartman 225896fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on) 225996fd7ce5SGreg Kroah-Hartman { 226089c8d91eSAlan Cox struct tty_struct *tty = file_tty(filp); 2261a8f3a297SPeter Hurley int retval = -ENOTTY; 226289c8d91eSAlan Cox 226389c8d91eSAlan Cox tty_lock(tty); 2264a8f3a297SPeter Hurley if (!tty_hung_up_p(filp)) 226596fd7ce5SGreg Kroah-Hartman retval = __tty_fasync(fd, filp, on); 226689c8d91eSAlan Cox tty_unlock(tty); 226789c8d91eSAlan Cox 226896fd7ce5SGreg Kroah-Hartman return retval; 226996fd7ce5SGreg Kroah-Hartman } 227096fd7ce5SGreg Kroah-Hartman 227196fd7ce5SGreg Kroah-Hartman /** 227296fd7ce5SGreg Kroah-Hartman * tiocsti - fake input character 227396fd7ce5SGreg Kroah-Hartman * @tty: tty to fake input into 227496fd7ce5SGreg Kroah-Hartman * @p: pointer to character 227596fd7ce5SGreg Kroah-Hartman * 227696fd7ce5SGreg Kroah-Hartman * Fake input to a tty device. Does the necessary locking and 227796fd7ce5SGreg Kroah-Hartman * input management. 227896fd7ce5SGreg Kroah-Hartman * 227996fd7ce5SGreg Kroah-Hartman * FIXME: does not honour flow control ?? 228096fd7ce5SGreg Kroah-Hartman * 228196fd7ce5SGreg Kroah-Hartman * Locking: 2282137084bbSPeter Hurley * Called functions take tty_ldiscs_lock 228396fd7ce5SGreg Kroah-Hartman * current->signal->tty check is safe without locks 228496fd7ce5SGreg Kroah-Hartman * 228596fd7ce5SGreg Kroah-Hartman * FIXME: may race normal receive processing 228696fd7ce5SGreg Kroah-Hartman */ 228796fd7ce5SGreg Kroah-Hartman 228896fd7ce5SGreg Kroah-Hartman static int tiocsti(struct tty_struct *tty, char __user *p) 228996fd7ce5SGreg Kroah-Hartman { 229096fd7ce5SGreg Kroah-Hartman char ch, mbz = 0; 229196fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 229296fd7ce5SGreg Kroah-Hartman 229396fd7ce5SGreg Kroah-Hartman if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) 229496fd7ce5SGreg Kroah-Hartman return -EPERM; 229596fd7ce5SGreg Kroah-Hartman if (get_user(ch, p)) 229696fd7ce5SGreg Kroah-Hartman return -EFAULT; 229796fd7ce5SGreg Kroah-Hartman tty_audit_tiocsti(tty, ch); 229896fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2299e55afd11SPeter Hurley if (!ld) 2300e55afd11SPeter Hurley return -EIO; 230196fd7ce5SGreg Kroah-Hartman ld->ops->receive_buf(tty, &ch, &mbz, 1); 230296fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 230396fd7ce5SGreg Kroah-Hartman return 0; 230496fd7ce5SGreg Kroah-Hartman } 230596fd7ce5SGreg Kroah-Hartman 230696fd7ce5SGreg Kroah-Hartman /** 230796fd7ce5SGreg Kroah-Hartman * tiocgwinsz - implement window query ioctl 230896fd7ce5SGreg Kroah-Hartman * @tty; tty 230996fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 231096fd7ce5SGreg Kroah-Hartman * 231196fd7ce5SGreg Kroah-Hartman * Copies the kernel idea of the window size into the user buffer. 231296fd7ce5SGreg Kroah-Hartman * 2313dee4a0beSPeter Hurley * Locking: tty->winsize_mutex is taken to ensure the winsize data 231496fd7ce5SGreg Kroah-Hartman * is consistent. 231596fd7ce5SGreg Kroah-Hartman */ 231696fd7ce5SGreg Kroah-Hartman 231796fd7ce5SGreg Kroah-Hartman static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) 231896fd7ce5SGreg Kroah-Hartman { 231996fd7ce5SGreg Kroah-Hartman int err; 232096fd7ce5SGreg Kroah-Hartman 2321dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 232296fd7ce5SGreg Kroah-Hartman err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); 2323dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 232496fd7ce5SGreg Kroah-Hartman 232596fd7ce5SGreg Kroah-Hartman return err ? -EFAULT: 0; 232696fd7ce5SGreg Kroah-Hartman } 232796fd7ce5SGreg Kroah-Hartman 232896fd7ce5SGreg Kroah-Hartman /** 232996fd7ce5SGreg Kroah-Hartman * tty_do_resize - resize event 233096fd7ce5SGreg Kroah-Hartman * @tty: tty being resized 233196fd7ce5SGreg Kroah-Hartman * @rows: rows (character) 233296fd7ce5SGreg Kroah-Hartman * @cols: cols (character) 233396fd7ce5SGreg Kroah-Hartman * 233496fd7ce5SGreg Kroah-Hartman * Update the termios variables and send the necessary signals to 233596fd7ce5SGreg Kroah-Hartman * peform a terminal resize correctly 233696fd7ce5SGreg Kroah-Hartman */ 233796fd7ce5SGreg Kroah-Hartman 233896fd7ce5SGreg Kroah-Hartman int tty_do_resize(struct tty_struct *tty, struct winsize *ws) 233996fd7ce5SGreg Kroah-Hartman { 234096fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 234196fd7ce5SGreg Kroah-Hartman 234296fd7ce5SGreg Kroah-Hartman /* Lock the tty */ 2343dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 234496fd7ce5SGreg Kroah-Hartman if (!memcmp(ws, &tty->winsize, sizeof(*ws))) 234596fd7ce5SGreg Kroah-Hartman goto done; 234696fd7ce5SGreg Kroah-Hartman 23475b239542SPeter Hurley /* Signal the foreground process group */ 23485b239542SPeter Hurley pgrp = tty_get_pgrp(tty); 234996fd7ce5SGreg Kroah-Hartman if (pgrp) 235096fd7ce5SGreg Kroah-Hartman kill_pgrp(pgrp, SIGWINCH, 1); 235196fd7ce5SGreg Kroah-Hartman put_pid(pgrp); 235296fd7ce5SGreg Kroah-Hartman 235396fd7ce5SGreg Kroah-Hartman tty->winsize = *ws; 235496fd7ce5SGreg Kroah-Hartman done: 2355dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 235696fd7ce5SGreg Kroah-Hartman return 0; 235796fd7ce5SGreg Kroah-Hartman } 23584d334fd1SMartin Schwidefsky EXPORT_SYMBOL(tty_do_resize); 235996fd7ce5SGreg Kroah-Hartman 236096fd7ce5SGreg Kroah-Hartman /** 236196fd7ce5SGreg Kroah-Hartman * tiocswinsz - implement window size set ioctl 236296fd7ce5SGreg Kroah-Hartman * @tty; tty side of tty 236396fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 236496fd7ce5SGreg Kroah-Hartman * 236596fd7ce5SGreg Kroah-Hartman * Copies the user idea of the window size to the kernel. Traditionally 236696fd7ce5SGreg Kroah-Hartman * this is just advisory information but for the Linux console it 236796fd7ce5SGreg Kroah-Hartman * actually has driver level meaning and triggers a VC resize. 236896fd7ce5SGreg Kroah-Hartman * 236996fd7ce5SGreg Kroah-Hartman * Locking: 237025985edcSLucas De Marchi * Driver dependent. The default do_resize method takes the 237196fd7ce5SGreg Kroah-Hartman * tty termios mutex and ctrl_lock. The console takes its own lock 237296fd7ce5SGreg Kroah-Hartman * then calls into the default method. 237396fd7ce5SGreg Kroah-Hartman */ 237496fd7ce5SGreg Kroah-Hartman 237596fd7ce5SGreg Kroah-Hartman static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) 237696fd7ce5SGreg Kroah-Hartman { 237796fd7ce5SGreg Kroah-Hartman struct winsize tmp_ws; 237896fd7ce5SGreg Kroah-Hartman if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) 237996fd7ce5SGreg Kroah-Hartman return -EFAULT; 238096fd7ce5SGreg Kroah-Hartman 238196fd7ce5SGreg Kroah-Hartman if (tty->ops->resize) 238296fd7ce5SGreg Kroah-Hartman return tty->ops->resize(tty, &tmp_ws); 238396fd7ce5SGreg Kroah-Hartman else 238496fd7ce5SGreg Kroah-Hartman return tty_do_resize(tty, &tmp_ws); 238596fd7ce5SGreg Kroah-Hartman } 238696fd7ce5SGreg Kroah-Hartman 238796fd7ce5SGreg Kroah-Hartman /** 238896fd7ce5SGreg Kroah-Hartman * tioccons - allow admin to move logical console 238996fd7ce5SGreg Kroah-Hartman * @file: the file to become console 239096fd7ce5SGreg Kroah-Hartman * 239125985edcSLucas De Marchi * Allow the administrator to move the redirected console device 239296fd7ce5SGreg Kroah-Hartman * 239396fd7ce5SGreg Kroah-Hartman * Locking: uses redirect_lock to guard the redirect information 239496fd7ce5SGreg Kroah-Hartman */ 239596fd7ce5SGreg Kroah-Hartman 239696fd7ce5SGreg Kroah-Hartman static int tioccons(struct file *file) 239796fd7ce5SGreg Kroah-Hartman { 239896fd7ce5SGreg Kroah-Hartman if (!capable(CAP_SYS_ADMIN)) 239996fd7ce5SGreg Kroah-Hartman return -EPERM; 240096fd7ce5SGreg Kroah-Hartman if (file->f_op->write == redirected_tty_write) { 240196fd7ce5SGreg Kroah-Hartman struct file *f; 240296fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 240396fd7ce5SGreg Kroah-Hartman f = redirect; 240496fd7ce5SGreg Kroah-Hartman redirect = NULL; 240596fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 240696fd7ce5SGreg Kroah-Hartman if (f) 240796fd7ce5SGreg Kroah-Hartman fput(f); 240896fd7ce5SGreg Kroah-Hartman return 0; 240996fd7ce5SGreg Kroah-Hartman } 241096fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 241196fd7ce5SGreg Kroah-Hartman if (redirect) { 241296fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 241396fd7ce5SGreg Kroah-Hartman return -EBUSY; 241496fd7ce5SGreg Kroah-Hartman } 2415cb0942b8SAl Viro redirect = get_file(file); 241696fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 241796fd7ce5SGreg Kroah-Hartman return 0; 241896fd7ce5SGreg Kroah-Hartman } 241996fd7ce5SGreg Kroah-Hartman 242096fd7ce5SGreg Kroah-Hartman /** 242196fd7ce5SGreg Kroah-Hartman * fionbio - non blocking ioctl 242296fd7ce5SGreg Kroah-Hartman * @file: file to set blocking value 242396fd7ce5SGreg Kroah-Hartman * @p: user parameter 242496fd7ce5SGreg Kroah-Hartman * 242596fd7ce5SGreg Kroah-Hartman * Historical tty interfaces had a blocking control ioctl before 242696fd7ce5SGreg Kroah-Hartman * the generic functionality existed. This piece of history is preserved 242796fd7ce5SGreg Kroah-Hartman * in the expected tty API of posix OS's. 242896fd7ce5SGreg Kroah-Hartman * 242996fd7ce5SGreg Kroah-Hartman * Locking: none, the open file handle ensures it won't go away. 243096fd7ce5SGreg Kroah-Hartman */ 243196fd7ce5SGreg Kroah-Hartman 243296fd7ce5SGreg Kroah-Hartman static int fionbio(struct file *file, int __user *p) 243396fd7ce5SGreg Kroah-Hartman { 243496fd7ce5SGreg Kroah-Hartman int nonblock; 243596fd7ce5SGreg Kroah-Hartman 243696fd7ce5SGreg Kroah-Hartman if (get_user(nonblock, p)) 243796fd7ce5SGreg Kroah-Hartman return -EFAULT; 243896fd7ce5SGreg Kroah-Hartman 243996fd7ce5SGreg Kroah-Hartman spin_lock(&file->f_lock); 244096fd7ce5SGreg Kroah-Hartman if (nonblock) 244196fd7ce5SGreg Kroah-Hartman file->f_flags |= O_NONBLOCK; 244296fd7ce5SGreg Kroah-Hartman else 244396fd7ce5SGreg Kroah-Hartman file->f_flags &= ~O_NONBLOCK; 244496fd7ce5SGreg Kroah-Hartman spin_unlock(&file->f_lock); 244596fd7ce5SGreg Kroah-Hartman return 0; 244696fd7ce5SGreg Kroah-Hartman } 244796fd7ce5SGreg Kroah-Hartman 244896fd7ce5SGreg Kroah-Hartman /** 244996fd7ce5SGreg Kroah-Hartman * tiocsctty - set controlling tty 245096fd7ce5SGreg Kroah-Hartman * @tty: tty structure 245196fd7ce5SGreg Kroah-Hartman * @arg: user argument 245296fd7ce5SGreg Kroah-Hartman * 245396fd7ce5SGreg Kroah-Hartman * This ioctl is used to manage job control. It permits a session 245496fd7ce5SGreg Kroah-Hartman * leader to set this tty as the controlling tty for the session. 245596fd7ce5SGreg Kroah-Hartman * 245696fd7ce5SGreg Kroah-Hartman * Locking: 2457e218eb32SPeter Hurley * Takes tty_lock() to serialize proc_set_tty() for this tty 245896fd7ce5SGreg Kroah-Hartman * Takes tasklist_lock internally to walk sessions 245996fd7ce5SGreg Kroah-Hartman * Takes ->siglock() when updating signal->tty 246096fd7ce5SGreg Kroah-Hartman */ 246196fd7ce5SGreg Kroah-Hartman 24620c556271SJann Horn static int tiocsctty(struct tty_struct *tty, struct file *file, int arg) 246396fd7ce5SGreg Kroah-Hartman { 246496fd7ce5SGreg Kroah-Hartman int ret = 0; 246596fd7ce5SGreg Kroah-Hartman 2466e218eb32SPeter Hurley tty_lock(tty); 24672c411c11SPeter Hurley read_lock(&tasklist_lock); 24682c411c11SPeter Hurley 24692c411c11SPeter Hurley if (current->signal->leader && (task_session(current) == tty->session)) 24702c411c11SPeter Hurley goto unlock; 24712c411c11SPeter Hurley 247296fd7ce5SGreg Kroah-Hartman /* 247396fd7ce5SGreg Kroah-Hartman * The process must be a session leader and 247496fd7ce5SGreg Kroah-Hartman * not have a controlling tty already. 247596fd7ce5SGreg Kroah-Hartman */ 247696fd7ce5SGreg Kroah-Hartman if (!current->signal->leader || current->signal->tty) { 247796fd7ce5SGreg Kroah-Hartman ret = -EPERM; 247896fd7ce5SGreg Kroah-Hartman goto unlock; 247996fd7ce5SGreg Kroah-Hartman } 248096fd7ce5SGreg Kroah-Hartman 248196fd7ce5SGreg Kroah-Hartman if (tty->session) { 248296fd7ce5SGreg Kroah-Hartman /* 248396fd7ce5SGreg Kroah-Hartman * This tty is already the controlling 248496fd7ce5SGreg Kroah-Hartman * tty for another session group! 248596fd7ce5SGreg Kroah-Hartman */ 248696fd7ce5SGreg Kroah-Hartman if (arg == 1 && capable(CAP_SYS_ADMIN)) { 248796fd7ce5SGreg Kroah-Hartman /* 248896fd7ce5SGreg Kroah-Hartman * Steal it away 248996fd7ce5SGreg Kroah-Hartman */ 249096fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 249196fd7ce5SGreg Kroah-Hartman } else { 249296fd7ce5SGreg Kroah-Hartman ret = -EPERM; 249396fd7ce5SGreg Kroah-Hartman goto unlock; 249496fd7ce5SGreg Kroah-Hartman } 249596fd7ce5SGreg Kroah-Hartman } 24960c556271SJann Horn 24970c556271SJann Horn /* See the comment in tty_open(). */ 24980c556271SJann Horn if ((file->f_mode & FMODE_READ) == 0 && !capable(CAP_SYS_ADMIN)) { 24990c556271SJann Horn ret = -EPERM; 25000c556271SJann Horn goto unlock; 25010c556271SJann Horn } 25020c556271SJann Horn 2503bce65f18SPeter Hurley proc_set_tty(tty); 250496fd7ce5SGreg Kroah-Hartman unlock: 25052c411c11SPeter Hurley read_unlock(&tasklist_lock); 2506e218eb32SPeter Hurley tty_unlock(tty); 250796fd7ce5SGreg Kroah-Hartman return ret; 250896fd7ce5SGreg Kroah-Hartman } 250996fd7ce5SGreg Kroah-Hartman 251096fd7ce5SGreg Kroah-Hartman /** 251196fd7ce5SGreg Kroah-Hartman * tty_get_pgrp - return a ref counted pgrp pid 251296fd7ce5SGreg Kroah-Hartman * @tty: tty to read 251396fd7ce5SGreg Kroah-Hartman * 251496fd7ce5SGreg Kroah-Hartman * Returns a refcounted instance of the pid struct for the process 251596fd7ce5SGreg Kroah-Hartman * group controlling the tty. 251696fd7ce5SGreg Kroah-Hartman */ 251796fd7ce5SGreg Kroah-Hartman 251896fd7ce5SGreg Kroah-Hartman struct pid *tty_get_pgrp(struct tty_struct *tty) 251996fd7ce5SGreg Kroah-Hartman { 252096fd7ce5SGreg Kroah-Hartman unsigned long flags; 252196fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 252296fd7ce5SGreg Kroah-Hartman 252396fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 252496fd7ce5SGreg Kroah-Hartman pgrp = get_pid(tty->pgrp); 252596fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 252696fd7ce5SGreg Kroah-Hartman 252796fd7ce5SGreg Kroah-Hartman return pgrp; 252896fd7ce5SGreg Kroah-Hartman } 252996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_get_pgrp); 253096fd7ce5SGreg Kroah-Hartman 2531e1c2296cSPeter Hurley /* 2532e1c2296cSPeter Hurley * This checks not only the pgrp, but falls back on the pid if no 2533e1c2296cSPeter Hurley * satisfactory pgrp is found. I dunno - gdb doesn't work correctly 2534e1c2296cSPeter Hurley * without this... 2535e1c2296cSPeter Hurley * 2536e1c2296cSPeter Hurley * The caller must hold rcu lock or the tasklist lock. 2537e1c2296cSPeter Hurley */ 2538e1c2296cSPeter Hurley static struct pid *session_of_pgrp(struct pid *pgrp) 2539e1c2296cSPeter Hurley { 2540e1c2296cSPeter Hurley struct task_struct *p; 2541e1c2296cSPeter Hurley struct pid *sid = NULL; 2542e1c2296cSPeter Hurley 2543e1c2296cSPeter Hurley p = pid_task(pgrp, PIDTYPE_PGID); 2544e1c2296cSPeter Hurley if (p == NULL) 2545e1c2296cSPeter Hurley p = pid_task(pgrp, PIDTYPE_PID); 2546e1c2296cSPeter Hurley if (p != NULL) 2547e1c2296cSPeter Hurley sid = task_session(p); 2548e1c2296cSPeter Hurley 2549e1c2296cSPeter Hurley return sid; 2550e1c2296cSPeter Hurley } 2551e1c2296cSPeter Hurley 255296fd7ce5SGreg Kroah-Hartman /** 255396fd7ce5SGreg Kroah-Hartman * tiocgpgrp - get process group 255496fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 255525985edcSLucas De Marchi * @real_tty: tty side of the tty passed by the user if a pty else the tty 255696fd7ce5SGreg Kroah-Hartman * @p: returned pid 255796fd7ce5SGreg Kroah-Hartman * 255896fd7ce5SGreg Kroah-Hartman * Obtain the process group of the tty. If there is no process group 255996fd7ce5SGreg Kroah-Hartman * return an error. 256096fd7ce5SGreg Kroah-Hartman * 256196fd7ce5SGreg Kroah-Hartman * Locking: none. Reference to current->signal->tty is safe. 256296fd7ce5SGreg Kroah-Hartman */ 256396fd7ce5SGreg Kroah-Hartman 256496fd7ce5SGreg Kroah-Hartman static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 256596fd7ce5SGreg Kroah-Hartman { 256696fd7ce5SGreg Kroah-Hartman struct pid *pid; 256796fd7ce5SGreg Kroah-Hartman int ret; 256896fd7ce5SGreg Kroah-Hartman /* 256996fd7ce5SGreg Kroah-Hartman * (tty == real_tty) is a cheap way of 257096fd7ce5SGreg Kroah-Hartman * testing if the tty is NOT a master pty. 257196fd7ce5SGreg Kroah-Hartman */ 257296fd7ce5SGreg Kroah-Hartman if (tty == real_tty && current->signal->tty != real_tty) 257396fd7ce5SGreg Kroah-Hartman return -ENOTTY; 257496fd7ce5SGreg Kroah-Hartman pid = tty_get_pgrp(real_tty); 257596fd7ce5SGreg Kroah-Hartman ret = put_user(pid_vnr(pid), p); 257696fd7ce5SGreg Kroah-Hartman put_pid(pid); 257796fd7ce5SGreg Kroah-Hartman return ret; 257896fd7ce5SGreg Kroah-Hartman } 257996fd7ce5SGreg Kroah-Hartman 258096fd7ce5SGreg Kroah-Hartman /** 258196fd7ce5SGreg Kroah-Hartman * tiocspgrp - attempt to set process group 258296fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 258396fd7ce5SGreg Kroah-Hartman * @real_tty: tty side device matching tty passed by user 258496fd7ce5SGreg Kroah-Hartman * @p: pid pointer 258596fd7ce5SGreg Kroah-Hartman * 258696fd7ce5SGreg Kroah-Hartman * Set the process group of the tty to the session passed. Only 258796fd7ce5SGreg Kroah-Hartman * permitted where the tty session is our session. 258896fd7ce5SGreg Kroah-Hartman * 258996fd7ce5SGreg Kroah-Hartman * Locking: RCU, ctrl lock 259096fd7ce5SGreg Kroah-Hartman */ 259196fd7ce5SGreg Kroah-Hartman 259296fd7ce5SGreg Kroah-Hartman static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 259396fd7ce5SGreg Kroah-Hartman { 259496fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 259596fd7ce5SGreg Kroah-Hartman pid_t pgrp_nr; 259696fd7ce5SGreg Kroah-Hartman int retval = tty_check_change(real_tty); 259796fd7ce5SGreg Kroah-Hartman 259896fd7ce5SGreg Kroah-Hartman if (retval == -EIO) 259996fd7ce5SGreg Kroah-Hartman return -ENOTTY; 260096fd7ce5SGreg Kroah-Hartman if (retval) 260196fd7ce5SGreg Kroah-Hartman return retval; 260296fd7ce5SGreg Kroah-Hartman if (!current->signal->tty || 260396fd7ce5SGreg Kroah-Hartman (current->signal->tty != real_tty) || 260496fd7ce5SGreg Kroah-Hartman (real_tty->session != task_session(current))) 260596fd7ce5SGreg Kroah-Hartman return -ENOTTY; 260696fd7ce5SGreg Kroah-Hartman if (get_user(pgrp_nr, p)) 260796fd7ce5SGreg Kroah-Hartman return -EFAULT; 260896fd7ce5SGreg Kroah-Hartman if (pgrp_nr < 0) 260996fd7ce5SGreg Kroah-Hartman return -EINVAL; 261096fd7ce5SGreg Kroah-Hartman rcu_read_lock(); 261196fd7ce5SGreg Kroah-Hartman pgrp = find_vpid(pgrp_nr); 261296fd7ce5SGreg Kroah-Hartman retval = -ESRCH; 261396fd7ce5SGreg Kroah-Hartman if (!pgrp) 261496fd7ce5SGreg Kroah-Hartman goto out_unlock; 261596fd7ce5SGreg Kroah-Hartman retval = -EPERM; 261696fd7ce5SGreg Kroah-Hartman if (session_of_pgrp(pgrp) != task_session(current)) 261796fd7ce5SGreg Kroah-Hartman goto out_unlock; 261896fd7ce5SGreg Kroah-Hartman retval = 0; 26191e86b5bfSPeter Hurley spin_lock_irq(&tty->ctrl_lock); 262096fd7ce5SGreg Kroah-Hartman put_pid(real_tty->pgrp); 262196fd7ce5SGreg Kroah-Hartman real_tty->pgrp = get_pid(pgrp); 26221e86b5bfSPeter Hurley spin_unlock_irq(&tty->ctrl_lock); 262396fd7ce5SGreg Kroah-Hartman out_unlock: 262496fd7ce5SGreg Kroah-Hartman rcu_read_unlock(); 262596fd7ce5SGreg Kroah-Hartman return retval; 262696fd7ce5SGreg Kroah-Hartman } 262796fd7ce5SGreg Kroah-Hartman 262896fd7ce5SGreg Kroah-Hartman /** 262996fd7ce5SGreg Kroah-Hartman * tiocgsid - get session id 263096fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 263125985edcSLucas De Marchi * @real_tty: tty side of the tty passed by the user if a pty else the tty 263296fd7ce5SGreg Kroah-Hartman * @p: pointer to returned session id 263396fd7ce5SGreg Kroah-Hartman * 263496fd7ce5SGreg Kroah-Hartman * Obtain the session id of the tty. If there is no session 263596fd7ce5SGreg Kroah-Hartman * return an error. 263696fd7ce5SGreg Kroah-Hartman * 263796fd7ce5SGreg Kroah-Hartman * Locking: none. Reference to current->signal->tty is safe. 263896fd7ce5SGreg Kroah-Hartman */ 263996fd7ce5SGreg Kroah-Hartman 264096fd7ce5SGreg Kroah-Hartman static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 264196fd7ce5SGreg Kroah-Hartman { 264296fd7ce5SGreg Kroah-Hartman /* 264396fd7ce5SGreg Kroah-Hartman * (tty == real_tty) is a cheap way of 264496fd7ce5SGreg Kroah-Hartman * testing if the tty is NOT a master pty. 264596fd7ce5SGreg Kroah-Hartman */ 264696fd7ce5SGreg Kroah-Hartman if (tty == real_tty && current->signal->tty != real_tty) 264796fd7ce5SGreg Kroah-Hartman return -ENOTTY; 264896fd7ce5SGreg Kroah-Hartman if (!real_tty->session) 264996fd7ce5SGreg Kroah-Hartman return -ENOTTY; 265096fd7ce5SGreg Kroah-Hartman return put_user(pid_vnr(real_tty->session), p); 265196fd7ce5SGreg Kroah-Hartman } 265296fd7ce5SGreg Kroah-Hartman 265396fd7ce5SGreg Kroah-Hartman /** 265496fd7ce5SGreg Kroah-Hartman * tiocsetd - set line discipline 265596fd7ce5SGreg Kroah-Hartman * @tty: tty device 265696fd7ce5SGreg Kroah-Hartman * @p: pointer to user data 265796fd7ce5SGreg Kroah-Hartman * 265896fd7ce5SGreg Kroah-Hartman * Set the line discipline according to user request. 265996fd7ce5SGreg Kroah-Hartman * 266096fd7ce5SGreg Kroah-Hartman * Locking: see tty_set_ldisc, this function is just a helper 266196fd7ce5SGreg Kroah-Hartman */ 266296fd7ce5SGreg Kroah-Hartman 266396fd7ce5SGreg Kroah-Hartman static int tiocsetd(struct tty_struct *tty, int __user *p) 266496fd7ce5SGreg Kroah-Hartman { 2665c12da96fSPeter Hurley int disc; 266696fd7ce5SGreg Kroah-Hartman int ret; 266796fd7ce5SGreg Kroah-Hartman 2668c12da96fSPeter Hurley if (get_user(disc, p)) 266996fd7ce5SGreg Kroah-Hartman return -EFAULT; 267096fd7ce5SGreg Kroah-Hartman 2671c12da96fSPeter Hurley ret = tty_set_ldisc(tty, disc); 267296fd7ce5SGreg Kroah-Hartman 267396fd7ce5SGreg Kroah-Hartman return ret; 267496fd7ce5SGreg Kroah-Hartman } 267596fd7ce5SGreg Kroah-Hartman 267696fd7ce5SGreg Kroah-Hartman /** 26775c17c861SPeter Hurley * tiocgetd - get line discipline 26785c17c861SPeter Hurley * @tty: tty device 26795c17c861SPeter Hurley * @p: pointer to user data 26805c17c861SPeter Hurley * 26815c17c861SPeter Hurley * Retrieves the line discipline id directly from the ldisc. 26825c17c861SPeter Hurley * 26835c17c861SPeter Hurley * Locking: waits for ldisc reference (in case the line discipline 26845c17c861SPeter Hurley * is changing or the tty is being hungup) 26855c17c861SPeter Hurley */ 26865c17c861SPeter Hurley 26875c17c861SPeter Hurley static int tiocgetd(struct tty_struct *tty, int __user *p) 26885c17c861SPeter Hurley { 26895c17c861SPeter Hurley struct tty_ldisc *ld; 26905c17c861SPeter Hurley int ret; 26915c17c861SPeter Hurley 26925c17c861SPeter Hurley ld = tty_ldisc_ref_wait(tty); 2693e55afd11SPeter Hurley if (!ld) 2694e55afd11SPeter Hurley return -EIO; 26955c17c861SPeter Hurley ret = put_user(ld->ops->num, p); 26965c17c861SPeter Hurley tty_ldisc_deref(ld); 26975c17c861SPeter Hurley return ret; 26985c17c861SPeter Hurley } 26995c17c861SPeter Hurley 27005c17c861SPeter Hurley /** 270196fd7ce5SGreg Kroah-Hartman * send_break - performed time break 270296fd7ce5SGreg Kroah-Hartman * @tty: device to break on 270396fd7ce5SGreg Kroah-Hartman * @duration: timeout in mS 270496fd7ce5SGreg Kroah-Hartman * 270596fd7ce5SGreg Kroah-Hartman * Perform a timed break on hardware that lacks its own driver level 270696fd7ce5SGreg Kroah-Hartman * timed break functionality. 270796fd7ce5SGreg Kroah-Hartman * 270896fd7ce5SGreg Kroah-Hartman * Locking: 270996fd7ce5SGreg Kroah-Hartman * atomic_write_lock serializes 271096fd7ce5SGreg Kroah-Hartman * 271196fd7ce5SGreg Kroah-Hartman */ 271296fd7ce5SGreg Kroah-Hartman 271396fd7ce5SGreg Kroah-Hartman static int send_break(struct tty_struct *tty, unsigned int duration) 271496fd7ce5SGreg Kroah-Hartman { 271596fd7ce5SGreg Kroah-Hartman int retval; 271696fd7ce5SGreg Kroah-Hartman 271796fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl == NULL) 271896fd7ce5SGreg Kroah-Hartman return 0; 271996fd7ce5SGreg Kroah-Hartman 272096fd7ce5SGreg Kroah-Hartman if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) 272196fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, duration); 272296fd7ce5SGreg Kroah-Hartman else { 272396fd7ce5SGreg Kroah-Hartman /* Do the work ourselves */ 272496fd7ce5SGreg Kroah-Hartman if (tty_write_lock(tty, 0) < 0) 272596fd7ce5SGreg Kroah-Hartman return -EINTR; 272696fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, -1); 272796fd7ce5SGreg Kroah-Hartman if (retval) 272896fd7ce5SGreg Kroah-Hartman goto out; 272996fd7ce5SGreg Kroah-Hartman if (!signal_pending(current)) 273096fd7ce5SGreg Kroah-Hartman msleep_interruptible(duration); 273196fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, 0); 273296fd7ce5SGreg Kroah-Hartman out: 273396fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 273496fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 273596fd7ce5SGreg Kroah-Hartman retval = -EINTR; 273696fd7ce5SGreg Kroah-Hartman } 273796fd7ce5SGreg Kroah-Hartman return retval; 273896fd7ce5SGreg Kroah-Hartman } 273996fd7ce5SGreg Kroah-Hartman 274096fd7ce5SGreg Kroah-Hartman /** 274196fd7ce5SGreg Kroah-Hartman * tty_tiocmget - get modem status 274296fd7ce5SGreg Kroah-Hartman * @tty: tty device 274396fd7ce5SGreg Kroah-Hartman * @file: user file pointer 274496fd7ce5SGreg Kroah-Hartman * @p: pointer to result 274596fd7ce5SGreg Kroah-Hartman * 274696fd7ce5SGreg Kroah-Hartman * Obtain the modem status bits from the tty driver if the feature 274796fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 274896fd7ce5SGreg Kroah-Hartman * 274996fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 275096fd7ce5SGreg Kroah-Hartman */ 275196fd7ce5SGreg Kroah-Hartman 275260b33c13SAlan Cox static int tty_tiocmget(struct tty_struct *tty, int __user *p) 275396fd7ce5SGreg Kroah-Hartman { 275496fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 275596fd7ce5SGreg Kroah-Hartman 275696fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmget) { 275760b33c13SAlan Cox retval = tty->ops->tiocmget(tty); 275896fd7ce5SGreg Kroah-Hartman 275996fd7ce5SGreg Kroah-Hartman if (retval >= 0) 276096fd7ce5SGreg Kroah-Hartman retval = put_user(retval, p); 276196fd7ce5SGreg Kroah-Hartman } 276296fd7ce5SGreg Kroah-Hartman return retval; 276396fd7ce5SGreg Kroah-Hartman } 276496fd7ce5SGreg Kroah-Hartman 276596fd7ce5SGreg Kroah-Hartman /** 276696fd7ce5SGreg Kroah-Hartman * tty_tiocmset - set modem status 276796fd7ce5SGreg Kroah-Hartman * @tty: tty device 276896fd7ce5SGreg Kroah-Hartman * @cmd: command - clear bits, set bits or set all 276996fd7ce5SGreg Kroah-Hartman * @p: pointer to desired bits 277096fd7ce5SGreg Kroah-Hartman * 277196fd7ce5SGreg Kroah-Hartman * Set the modem status bits from the tty driver if the feature 277296fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 277396fd7ce5SGreg Kroah-Hartman * 277496fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 277596fd7ce5SGreg Kroah-Hartman */ 277696fd7ce5SGreg Kroah-Hartman 277720b9d177SAlan Cox static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, 277896fd7ce5SGreg Kroah-Hartman unsigned __user *p) 277996fd7ce5SGreg Kroah-Hartman { 278096fd7ce5SGreg Kroah-Hartman int retval; 278196fd7ce5SGreg Kroah-Hartman unsigned int set, clear, val; 278296fd7ce5SGreg Kroah-Hartman 278396fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmset == NULL) 278496fd7ce5SGreg Kroah-Hartman return -EINVAL; 278596fd7ce5SGreg Kroah-Hartman 278696fd7ce5SGreg Kroah-Hartman retval = get_user(val, p); 278796fd7ce5SGreg Kroah-Hartman if (retval) 278896fd7ce5SGreg Kroah-Hartman return retval; 278996fd7ce5SGreg Kroah-Hartman set = clear = 0; 279096fd7ce5SGreg Kroah-Hartman switch (cmd) { 279196fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 279296fd7ce5SGreg Kroah-Hartman set = val; 279396fd7ce5SGreg Kroah-Hartman break; 279496fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 279596fd7ce5SGreg Kroah-Hartman clear = val; 279696fd7ce5SGreg Kroah-Hartman break; 279796fd7ce5SGreg Kroah-Hartman case TIOCMSET: 279896fd7ce5SGreg Kroah-Hartman set = val; 279996fd7ce5SGreg Kroah-Hartman clear = ~val; 280096fd7ce5SGreg Kroah-Hartman break; 280196fd7ce5SGreg Kroah-Hartman } 280296fd7ce5SGreg Kroah-Hartman set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 280396fd7ce5SGreg Kroah-Hartman clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 280420b9d177SAlan Cox return tty->ops->tiocmset(tty, set, clear); 280596fd7ce5SGreg Kroah-Hartman } 280696fd7ce5SGreg Kroah-Hartman 280796fd7ce5SGreg Kroah-Hartman static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) 280896fd7ce5SGreg Kroah-Hartman { 280996fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 281096fd7ce5SGreg Kroah-Hartman struct serial_icounter_struct icount; 281196fd7ce5SGreg Kroah-Hartman memset(&icount, 0, sizeof(icount)); 281296fd7ce5SGreg Kroah-Hartman if (tty->ops->get_icount) 281396fd7ce5SGreg Kroah-Hartman retval = tty->ops->get_icount(tty, &icount); 281496fd7ce5SGreg Kroah-Hartman if (retval != 0) 281596fd7ce5SGreg Kroah-Hartman return retval; 281696fd7ce5SGreg Kroah-Hartman if (copy_to_user(arg, &icount, sizeof(icount))) 281796fd7ce5SGreg Kroah-Hartman return -EFAULT; 281896fd7ce5SGreg Kroah-Hartman return 0; 281996fd7ce5SGreg Kroah-Hartman } 282096fd7ce5SGreg Kroah-Hartman 28218a8ae62fSJiri Slaby static void tty_warn_deprecated_flags(struct serial_struct __user *ss) 28228a8ae62fSJiri Slaby { 28238a8ae62fSJiri Slaby static DEFINE_RATELIMIT_STATE(depr_flags, 28248a8ae62fSJiri Slaby DEFAULT_RATELIMIT_INTERVAL, 28258a8ae62fSJiri Slaby DEFAULT_RATELIMIT_BURST); 28268a8ae62fSJiri Slaby char comm[TASK_COMM_LEN]; 28278a8ae62fSJiri Slaby int flags; 28288a8ae62fSJiri Slaby 28298a8ae62fSJiri Slaby if (get_user(flags, &ss->flags)) 28308a8ae62fSJiri Slaby return; 28318a8ae62fSJiri Slaby 28328a8ae62fSJiri Slaby flags &= ASYNC_DEPRECATED; 28338a8ae62fSJiri Slaby 28348a8ae62fSJiri Slaby if (flags && __ratelimit(&depr_flags)) 28358a8ae62fSJiri Slaby pr_warning("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", 28368a8ae62fSJiri Slaby __func__, get_task_comm(comm, current), flags); 28378a8ae62fSJiri Slaby } 28388a8ae62fSJiri Slaby 28398f166e00SPeter Hurley /* 28408f166e00SPeter Hurley * if pty, return the slave side (real_tty) 28418f166e00SPeter Hurley * otherwise, return self 28428f166e00SPeter Hurley */ 28438f166e00SPeter Hurley static struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) 284496fd7ce5SGreg Kroah-Hartman { 284596fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 284696fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_MASTER) 284796fd7ce5SGreg Kroah-Hartman tty = tty->link; 284896fd7ce5SGreg Kroah-Hartman return tty; 284996fd7ce5SGreg Kroah-Hartman } 285096fd7ce5SGreg Kroah-Hartman 285196fd7ce5SGreg Kroah-Hartman /* 285296fd7ce5SGreg Kroah-Hartman * Split this up, as gcc can choke on it otherwise.. 285396fd7ce5SGreg Kroah-Hartman */ 285496fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 285596fd7ce5SGreg Kroah-Hartman { 285696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 285796fd7ce5SGreg Kroah-Hartman struct tty_struct *real_tty; 285896fd7ce5SGreg Kroah-Hartman void __user *p = (void __user *)arg; 285996fd7ce5SGreg Kroah-Hartman int retval; 286096fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 286196fd7ce5SGreg Kroah-Hartman 28626131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 286396fd7ce5SGreg Kroah-Hartman return -EINVAL; 286496fd7ce5SGreg Kroah-Hartman 286596fd7ce5SGreg Kroah-Hartman real_tty = tty_pair_get_tty(tty); 286696fd7ce5SGreg Kroah-Hartman 286796fd7ce5SGreg Kroah-Hartman /* 286896fd7ce5SGreg Kroah-Hartman * Factor out some common prep work 286996fd7ce5SGreg Kroah-Hartman */ 287096fd7ce5SGreg Kroah-Hartman switch (cmd) { 287196fd7ce5SGreg Kroah-Hartman case TIOCSETD: 287296fd7ce5SGreg Kroah-Hartman case TIOCSBRK: 287396fd7ce5SGreg Kroah-Hartman case TIOCCBRK: 287496fd7ce5SGreg Kroah-Hartman case TCSBRK: 287596fd7ce5SGreg Kroah-Hartman case TCSBRKP: 287696fd7ce5SGreg Kroah-Hartman retval = tty_check_change(tty); 287796fd7ce5SGreg Kroah-Hartman if (retval) 287896fd7ce5SGreg Kroah-Hartman return retval; 287996fd7ce5SGreg Kroah-Hartman if (cmd != TIOCCBRK) { 288096fd7ce5SGreg Kroah-Hartman tty_wait_until_sent(tty, 0); 288196fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 288296fd7ce5SGreg Kroah-Hartman return -EINTR; 288396fd7ce5SGreg Kroah-Hartman } 288496fd7ce5SGreg Kroah-Hartman break; 288596fd7ce5SGreg Kroah-Hartman } 288696fd7ce5SGreg Kroah-Hartman 288796fd7ce5SGreg Kroah-Hartman /* 288896fd7ce5SGreg Kroah-Hartman * Now do the stuff. 288996fd7ce5SGreg Kroah-Hartman */ 289096fd7ce5SGreg Kroah-Hartman switch (cmd) { 289196fd7ce5SGreg Kroah-Hartman case TIOCSTI: 289296fd7ce5SGreg Kroah-Hartman return tiocsti(tty, p); 289396fd7ce5SGreg Kroah-Hartman case TIOCGWINSZ: 289496fd7ce5SGreg Kroah-Hartman return tiocgwinsz(real_tty, p); 289596fd7ce5SGreg Kroah-Hartman case TIOCSWINSZ: 289696fd7ce5SGreg Kroah-Hartman return tiocswinsz(real_tty, p); 289796fd7ce5SGreg Kroah-Hartman case TIOCCONS: 289896fd7ce5SGreg Kroah-Hartman return real_tty != tty ? -EINVAL : tioccons(file); 289996fd7ce5SGreg Kroah-Hartman case FIONBIO: 290096fd7ce5SGreg Kroah-Hartman return fionbio(file, p); 290196fd7ce5SGreg Kroah-Hartman case TIOCEXCL: 290296fd7ce5SGreg Kroah-Hartman set_bit(TTY_EXCLUSIVE, &tty->flags); 290396fd7ce5SGreg Kroah-Hartman return 0; 290496fd7ce5SGreg Kroah-Hartman case TIOCNXCL: 290596fd7ce5SGreg Kroah-Hartman clear_bit(TTY_EXCLUSIVE, &tty->flags); 290696fd7ce5SGreg Kroah-Hartman return 0; 290784fd7bdfSCyrill Gorcunov case TIOCGEXCL: 290884fd7bdfSCyrill Gorcunov { 290984fd7bdfSCyrill Gorcunov int excl = test_bit(TTY_EXCLUSIVE, &tty->flags); 291084fd7bdfSCyrill Gorcunov return put_user(excl, (int __user *)p); 291184fd7bdfSCyrill Gorcunov } 291296fd7ce5SGreg Kroah-Hartman case TIOCNOTTY: 291396fd7ce5SGreg Kroah-Hartman if (current->signal->tty != tty) 291496fd7ce5SGreg Kroah-Hartman return -ENOTTY; 291596fd7ce5SGreg Kroah-Hartman no_tty(); 291696fd7ce5SGreg Kroah-Hartman return 0; 291796fd7ce5SGreg Kroah-Hartman case TIOCSCTTY: 2918d1d3a0f7SPeter Hurley return tiocsctty(real_tty, file, arg); 291996fd7ce5SGreg Kroah-Hartman case TIOCGPGRP: 292096fd7ce5SGreg Kroah-Hartman return tiocgpgrp(tty, real_tty, p); 292196fd7ce5SGreg Kroah-Hartman case TIOCSPGRP: 292296fd7ce5SGreg Kroah-Hartman return tiocspgrp(tty, real_tty, p); 292396fd7ce5SGreg Kroah-Hartman case TIOCGSID: 292496fd7ce5SGreg Kroah-Hartman return tiocgsid(tty, real_tty, p); 292596fd7ce5SGreg Kroah-Hartman case TIOCGETD: 29265c17c861SPeter Hurley return tiocgetd(tty, p); 292796fd7ce5SGreg Kroah-Hartman case TIOCSETD: 292896fd7ce5SGreg Kroah-Hartman return tiocsetd(tty, p); 29293c95c985SKay Sievers case TIOCVHANGUP: 29303c95c985SKay Sievers if (!capable(CAP_SYS_ADMIN)) 29313c95c985SKay Sievers return -EPERM; 29323c95c985SKay Sievers tty_vhangup(tty); 29333c95c985SKay Sievers return 0; 2934b7b8de08SWerner Fink case TIOCGDEV: 2935b7b8de08SWerner Fink { 2936b7b8de08SWerner Fink unsigned int ret = new_encode_dev(tty_devnum(real_tty)); 2937b7b8de08SWerner Fink return put_user(ret, (unsigned int __user *)p); 2938b7b8de08SWerner Fink } 293996fd7ce5SGreg Kroah-Hartman /* 294096fd7ce5SGreg Kroah-Hartman * Break handling 294196fd7ce5SGreg Kroah-Hartman */ 294296fd7ce5SGreg Kroah-Hartman case TIOCSBRK: /* Turn break on, unconditionally */ 294396fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 294496fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, -1); 294596fd7ce5SGreg Kroah-Hartman return 0; 294696fd7ce5SGreg Kroah-Hartman case TIOCCBRK: /* Turn break off, unconditionally */ 294796fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 294896fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, 0); 294996fd7ce5SGreg Kroah-Hartman return 0; 295096fd7ce5SGreg Kroah-Hartman case TCSBRK: /* SVID version: non-zero arg --> no break */ 295196fd7ce5SGreg Kroah-Hartman /* non-zero arg means wait for all output data 295296fd7ce5SGreg Kroah-Hartman * to be sent (performed above) but don't send break. 295396fd7ce5SGreg Kroah-Hartman * This is used by the tcdrain() termios function. 295496fd7ce5SGreg Kroah-Hartman */ 295596fd7ce5SGreg Kroah-Hartman if (!arg) 295696fd7ce5SGreg Kroah-Hartman return send_break(tty, 250); 295796fd7ce5SGreg Kroah-Hartman return 0; 295896fd7ce5SGreg Kroah-Hartman case TCSBRKP: /* support for POSIX tcsendbreak() */ 295996fd7ce5SGreg Kroah-Hartman return send_break(tty, arg ? arg*100 : 250); 296096fd7ce5SGreg Kroah-Hartman 296196fd7ce5SGreg Kroah-Hartman case TIOCMGET: 296260b33c13SAlan Cox return tty_tiocmget(tty, p); 296396fd7ce5SGreg Kroah-Hartman case TIOCMSET: 296496fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 296596fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 296620b9d177SAlan Cox return tty_tiocmset(tty, cmd, p); 296796fd7ce5SGreg Kroah-Hartman case TIOCGICOUNT: 296896fd7ce5SGreg Kroah-Hartman retval = tty_tiocgicount(tty, p); 296996fd7ce5SGreg Kroah-Hartman /* For the moment allow fall through to the old method */ 297096fd7ce5SGreg Kroah-Hartman if (retval != -EINVAL) 297196fd7ce5SGreg Kroah-Hartman return retval; 297296fd7ce5SGreg Kroah-Hartman break; 297396fd7ce5SGreg Kroah-Hartman case TCFLSH: 297496fd7ce5SGreg Kroah-Hartman switch (arg) { 297596fd7ce5SGreg Kroah-Hartman case TCIFLUSH: 297696fd7ce5SGreg Kroah-Hartman case TCIOFLUSH: 297796fd7ce5SGreg Kroah-Hartman /* flush tty buffer and allow ldisc to process ioctl */ 297886c80a8eSPeter Hurley tty_buffer_flush(tty, NULL); 297996fd7ce5SGreg Kroah-Hartman break; 298096fd7ce5SGreg Kroah-Hartman } 298196fd7ce5SGreg Kroah-Hartman break; 29828a8ae62fSJiri Slaby case TIOCSSERIAL: 29838a8ae62fSJiri Slaby tty_warn_deprecated_flags(p); 29848a8ae62fSJiri Slaby break; 298596fd7ce5SGreg Kroah-Hartman } 298696fd7ce5SGreg Kroah-Hartman if (tty->ops->ioctl) { 2987c961bfb1SPeter Hurley retval = tty->ops->ioctl(tty, cmd, arg); 298896fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 298996fd7ce5SGreg Kroah-Hartman return retval; 299096fd7ce5SGreg Kroah-Hartman } 299196fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 2992e55afd11SPeter Hurley if (!ld) 2993e55afd11SPeter Hurley return hung_up_tty_ioctl(file, cmd, arg); 299496fd7ce5SGreg Kroah-Hartman retval = -EINVAL; 299596fd7ce5SGreg Kroah-Hartman if (ld->ops->ioctl) { 299696fd7ce5SGreg Kroah-Hartman retval = ld->ops->ioctl(tty, file, cmd, arg); 299796fd7ce5SGreg Kroah-Hartman if (retval == -ENOIOCTLCMD) 2998bbb63c51SWanlong Gao retval = -ENOTTY; 299996fd7ce5SGreg Kroah-Hartman } 300096fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 300196fd7ce5SGreg Kroah-Hartman return retval; 300296fd7ce5SGreg Kroah-Hartman } 300396fd7ce5SGreg Kroah-Hartman 300496fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 300596fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 300696fd7ce5SGreg Kroah-Hartman unsigned long arg) 300796fd7ce5SGreg Kroah-Hartman { 300896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 300996fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 301096fd7ce5SGreg Kroah-Hartman int retval = -ENOIOCTLCMD; 301196fd7ce5SGreg Kroah-Hartman 30126131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 301396fd7ce5SGreg Kroah-Hartman return -EINVAL; 301496fd7ce5SGreg Kroah-Hartman 301596fd7ce5SGreg Kroah-Hartman if (tty->ops->compat_ioctl) { 3016c961bfb1SPeter Hurley retval = tty->ops->compat_ioctl(tty, cmd, arg); 301796fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 301896fd7ce5SGreg Kroah-Hartman return retval; 301996fd7ce5SGreg Kroah-Hartman } 302096fd7ce5SGreg Kroah-Hartman 302196fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 3022e55afd11SPeter Hurley if (!ld) 3023e55afd11SPeter Hurley return hung_up_tty_compat_ioctl(file, cmd, arg); 302496fd7ce5SGreg Kroah-Hartman if (ld->ops->compat_ioctl) 302596fd7ce5SGreg Kroah-Hartman retval = ld->ops->compat_ioctl(tty, file, cmd, arg); 30268193c429SThomas Meyer else 30278193c429SThomas Meyer retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg); 302896fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 302996fd7ce5SGreg Kroah-Hartman 303096fd7ce5SGreg Kroah-Hartman return retval; 303196fd7ce5SGreg Kroah-Hartman } 303296fd7ce5SGreg Kroah-Hartman #endif 303396fd7ce5SGreg Kroah-Hartman 3034c3c073f8SAl Viro static int this_tty(const void *t, struct file *file, unsigned fd) 3035c3c073f8SAl Viro { 3036c3c073f8SAl Viro if (likely(file->f_op->read != tty_read)) 3037c3c073f8SAl Viro return 0; 3038c3c073f8SAl Viro return file_tty(file) != t ? 0 : fd + 1; 3039c3c073f8SAl Viro } 3040c3c073f8SAl Viro 304196fd7ce5SGreg Kroah-Hartman /* 304296fd7ce5SGreg Kroah-Hartman * This implements the "Secure Attention Key" --- the idea is to 304396fd7ce5SGreg Kroah-Hartman * prevent trojan horses by killing all processes associated with this 304496fd7ce5SGreg Kroah-Hartman * tty when the user hits the "Secure Attention Key". Required for 304596fd7ce5SGreg Kroah-Hartman * super-paranoid applications --- see the Orange Book for more details. 304696fd7ce5SGreg Kroah-Hartman * 304796fd7ce5SGreg Kroah-Hartman * This code could be nicer; ideally it should send a HUP, wait a few 304896fd7ce5SGreg Kroah-Hartman * seconds, then send a INT, and then a KILL signal. But you then 304996fd7ce5SGreg Kroah-Hartman * have to coordinate with the init process, since all processes associated 305096fd7ce5SGreg Kroah-Hartman * with the current tty must be dead before the new getty is allowed 305196fd7ce5SGreg Kroah-Hartman * to spawn. 305296fd7ce5SGreg Kroah-Hartman * 305396fd7ce5SGreg Kroah-Hartman * Now, if it would be correct ;-/ The current code has a nasty hole - 305496fd7ce5SGreg Kroah-Hartman * it doesn't catch files in flight. We may send the descriptor to ourselves 305596fd7ce5SGreg Kroah-Hartman * via AF_UNIX socket, close it and later fetch from socket. FIXME. 305696fd7ce5SGreg Kroah-Hartman * 305796fd7ce5SGreg Kroah-Hartman * Nasty bug: do_SAK is being called in interrupt context. This can 305896fd7ce5SGreg Kroah-Hartman * deadlock. We punt it up to process context. AKPM - 16Mar2001 305996fd7ce5SGreg Kroah-Hartman */ 306096fd7ce5SGreg Kroah-Hartman void __do_SAK(struct tty_struct *tty) 306196fd7ce5SGreg Kroah-Hartman { 306296fd7ce5SGreg Kroah-Hartman #ifdef TTY_SOFT_SAK 306396fd7ce5SGreg Kroah-Hartman tty_hangup(tty); 306496fd7ce5SGreg Kroah-Hartman #else 306596fd7ce5SGreg Kroah-Hartman struct task_struct *g, *p; 306696fd7ce5SGreg Kroah-Hartman struct pid *session; 306796fd7ce5SGreg Kroah-Hartman int i; 306896fd7ce5SGreg Kroah-Hartman 306996fd7ce5SGreg Kroah-Hartman if (!tty) 307096fd7ce5SGreg Kroah-Hartman return; 307196fd7ce5SGreg Kroah-Hartman session = tty->session; 307296fd7ce5SGreg Kroah-Hartman 307396fd7ce5SGreg Kroah-Hartman tty_ldisc_flush(tty); 307496fd7ce5SGreg Kroah-Hartman 307596fd7ce5SGreg Kroah-Hartman tty_driver_flush_buffer(tty); 307696fd7ce5SGreg Kroah-Hartman 307796fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 307896fd7ce5SGreg Kroah-Hartman /* Kill the entire session */ 307996fd7ce5SGreg Kroah-Hartman do_each_pid_task(session, PIDTYPE_SID, p) { 30809b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by session\n", 308196fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 308296fd7ce5SGreg Kroah-Hartman send_sig(SIGKILL, p, 1); 308396fd7ce5SGreg Kroah-Hartman } while_each_pid_task(session, PIDTYPE_SID, p); 30849b42bb75SPeter Hurley 30859b42bb75SPeter Hurley /* Now kill any processes that happen to have the tty open */ 308696fd7ce5SGreg Kroah-Hartman do_each_thread(g, p) { 308796fd7ce5SGreg Kroah-Hartman if (p->signal->tty == tty) { 30889b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by controlling tty\n", 308996fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 309096fd7ce5SGreg Kroah-Hartman send_sig(SIGKILL, p, 1); 309196fd7ce5SGreg Kroah-Hartman continue; 309296fd7ce5SGreg Kroah-Hartman } 309396fd7ce5SGreg Kroah-Hartman task_lock(p); 3094c3c073f8SAl Viro i = iterate_fd(p->files, 0, this_tty, tty); 3095c3c073f8SAl Viro if (i != 0) { 30969b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by fd#%d\n", 3097c3c073f8SAl Viro task_pid_nr(p), p->comm, i - 1); 309896fd7ce5SGreg Kroah-Hartman force_sig(SIGKILL, p); 309996fd7ce5SGreg Kroah-Hartman } 310096fd7ce5SGreg Kroah-Hartman task_unlock(p); 310196fd7ce5SGreg Kroah-Hartman } while_each_thread(g, p); 310296fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 310396fd7ce5SGreg Kroah-Hartman #endif 310496fd7ce5SGreg Kroah-Hartman } 310596fd7ce5SGreg Kroah-Hartman 310696fd7ce5SGreg Kroah-Hartman static void do_SAK_work(struct work_struct *work) 310796fd7ce5SGreg Kroah-Hartman { 310896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 310996fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, SAK_work); 311096fd7ce5SGreg Kroah-Hartman __do_SAK(tty); 311196fd7ce5SGreg Kroah-Hartman } 311296fd7ce5SGreg Kroah-Hartman 311396fd7ce5SGreg Kroah-Hartman /* 311496fd7ce5SGreg Kroah-Hartman * The tq handling here is a little racy - tty->SAK_work may already be queued. 311596fd7ce5SGreg Kroah-Hartman * Fortunately we don't need to worry, because if ->SAK_work is already queued, 311696fd7ce5SGreg Kroah-Hartman * the values which we write to it will be identical to the values which it 311796fd7ce5SGreg Kroah-Hartman * already has. --akpm 311896fd7ce5SGreg Kroah-Hartman */ 311996fd7ce5SGreg Kroah-Hartman void do_SAK(struct tty_struct *tty) 312096fd7ce5SGreg Kroah-Hartman { 312196fd7ce5SGreg Kroah-Hartman if (!tty) 312296fd7ce5SGreg Kroah-Hartman return; 312396fd7ce5SGreg Kroah-Hartman schedule_work(&tty->SAK_work); 312496fd7ce5SGreg Kroah-Hartman } 312596fd7ce5SGreg Kroah-Hartman 312696fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(do_SAK); 312796fd7ce5SGreg Kroah-Hartman 31286e9430acSGreg Kroah-Hartman static int dev_match_devt(struct device *dev, const void *data) 312996fd7ce5SGreg Kroah-Hartman { 31306e9430acSGreg Kroah-Hartman const dev_t *devt = data; 313196fd7ce5SGreg Kroah-Hartman return dev->devt == *devt; 313296fd7ce5SGreg Kroah-Hartman } 313396fd7ce5SGreg Kroah-Hartman 313496fd7ce5SGreg Kroah-Hartman /* Must put_device() after it's unused! */ 313596fd7ce5SGreg Kroah-Hartman static struct device *tty_get_device(struct tty_struct *tty) 313696fd7ce5SGreg Kroah-Hartman { 313796fd7ce5SGreg Kroah-Hartman dev_t devt = tty_devnum(tty); 313896fd7ce5SGreg Kroah-Hartman return class_find_device(tty_class, NULL, &devt, dev_match_devt); 313996fd7ce5SGreg Kroah-Hartman } 314096fd7ce5SGreg Kroah-Hartman 314196fd7ce5SGreg Kroah-Hartman 314296fd7ce5SGreg Kroah-Hartman /** 31432c964a2fSRasmus Villemoes * alloc_tty_struct 314496fd7ce5SGreg Kroah-Hartman * 31452c964a2fSRasmus Villemoes * This subroutine allocates and initializes a tty structure. 314696fd7ce5SGreg Kroah-Hartman * 31472c964a2fSRasmus Villemoes * Locking: none - tty in question is not exposed at this point 314896fd7ce5SGreg Kroah-Hartman */ 314996fd7ce5SGreg Kroah-Hartman 31502c964a2fSRasmus Villemoes struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx) 315196fd7ce5SGreg Kroah-Hartman { 31522c964a2fSRasmus Villemoes struct tty_struct *tty; 31532c964a2fSRasmus Villemoes 31542c964a2fSRasmus Villemoes tty = kzalloc(sizeof(*tty), GFP_KERNEL); 31552c964a2fSRasmus Villemoes if (!tty) 31562c964a2fSRasmus Villemoes return NULL; 31572c964a2fSRasmus Villemoes 315896fd7ce5SGreg Kroah-Hartman kref_init(&tty->kref); 315996fd7ce5SGreg Kroah-Hartman tty->magic = TTY_MAGIC; 316096fd7ce5SGreg Kroah-Hartman tty_ldisc_init(tty); 316196fd7ce5SGreg Kroah-Hartman tty->session = NULL; 316296fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 316389c8d91eSAlan Cox mutex_init(&tty->legacy_mutex); 3164d8c1f929SPeter Hurley mutex_init(&tty->throttle_mutex); 31656a1c0680SPeter Hurley init_rwsem(&tty->termios_rwsem); 3166dee4a0beSPeter Hurley mutex_init(&tty->winsize_mutex); 316736697529SPeter Hurley init_ldsem(&tty->ldisc_sem); 316896fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->write_wait); 316996fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->read_wait); 317096fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, do_tty_hangup); 317196fd7ce5SGreg Kroah-Hartman mutex_init(&tty->atomic_write_lock); 317296fd7ce5SGreg Kroah-Hartman spin_lock_init(&tty->ctrl_lock); 3173f9e053dcSPeter Hurley spin_lock_init(&tty->flow_lock); 31744a510969SPeter Hurley spin_lock_init(&tty->files_lock); 317596fd7ce5SGreg Kroah-Hartman INIT_LIST_HEAD(&tty->tty_files); 317696fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->SAK_work, do_SAK_work); 317796fd7ce5SGreg Kroah-Hartman 317896fd7ce5SGreg Kroah-Hartman tty->driver = driver; 317996fd7ce5SGreg Kroah-Hartman tty->ops = driver->ops; 318096fd7ce5SGreg Kroah-Hartman tty->index = idx; 318196fd7ce5SGreg Kroah-Hartman tty_line_name(driver, idx, tty->name); 318296fd7ce5SGreg Kroah-Hartman tty->dev = tty_get_device(tty); 31832c964a2fSRasmus Villemoes 31842c964a2fSRasmus Villemoes return tty; 318596fd7ce5SGreg Kroah-Hartman } 318696fd7ce5SGreg Kroah-Hartman 318796fd7ce5SGreg Kroah-Hartman /** 318896fd7ce5SGreg Kroah-Hartman * tty_put_char - write one character to a tty 318996fd7ce5SGreg Kroah-Hartman * @tty: tty 319096fd7ce5SGreg Kroah-Hartman * @ch: character 319196fd7ce5SGreg Kroah-Hartman * 319296fd7ce5SGreg Kroah-Hartman * Write one byte to the tty using the provided put_char method 319396fd7ce5SGreg Kroah-Hartman * if present. Returns the number of characters successfully output. 319496fd7ce5SGreg Kroah-Hartman * 319596fd7ce5SGreg Kroah-Hartman * Note: the specific put_char operation in the driver layer may go 319696fd7ce5SGreg Kroah-Hartman * away soon. Don't call it directly, use this method 319796fd7ce5SGreg Kroah-Hartman */ 319896fd7ce5SGreg Kroah-Hartman 319996fd7ce5SGreg Kroah-Hartman int tty_put_char(struct tty_struct *tty, unsigned char ch) 320096fd7ce5SGreg Kroah-Hartman { 320196fd7ce5SGreg Kroah-Hartman if (tty->ops->put_char) 320296fd7ce5SGreg Kroah-Hartman return tty->ops->put_char(tty, ch); 320396fd7ce5SGreg Kroah-Hartman return tty->ops->write(tty, &ch, 1); 320496fd7ce5SGreg Kroah-Hartman } 320596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_put_char); 320696fd7ce5SGreg Kroah-Hartman 320796fd7ce5SGreg Kroah-Hartman struct class *tty_class; 320896fd7ce5SGreg Kroah-Hartman 32097e73eca6SJiri Slaby static int tty_cdev_add(struct tty_driver *driver, dev_t dev, 32107e73eca6SJiri Slaby unsigned int index, unsigned int count) 32117e73eca6SJiri Slaby { 3212c1a752baSLeon Yu int err; 3213c1a752baSLeon Yu 32147e73eca6SJiri Slaby /* init here, since reused cdevs cause crashes */ 3215a3a10ce3SRichard Watts driver->cdevs[index] = cdev_alloc(); 3216a3a10ce3SRichard Watts if (!driver->cdevs[index]) 3217a3a10ce3SRichard Watts return -ENOMEM; 3218c1a752baSLeon Yu driver->cdevs[index]->ops = &tty_fops; 3219a3a10ce3SRichard Watts driver->cdevs[index]->owner = driver->owner; 3220c1a752baSLeon Yu err = cdev_add(driver->cdevs[index], dev, count); 3221c1a752baSLeon Yu if (err) 3222c1a752baSLeon Yu kobject_put(&driver->cdevs[index]->kobj); 3223c1a752baSLeon Yu return err; 32247e73eca6SJiri Slaby } 32257e73eca6SJiri Slaby 322696fd7ce5SGreg Kroah-Hartman /** 322796fd7ce5SGreg Kroah-Hartman * tty_register_device - register a tty device 322896fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 322996fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 323096fd7ce5SGreg Kroah-Hartman * @device: a struct device that is associated with this tty device. 323196fd7ce5SGreg Kroah-Hartman * This field is optional, if there is no known struct device 323296fd7ce5SGreg Kroah-Hartman * for this tty device it can be set to NULL safely. 323396fd7ce5SGreg Kroah-Hartman * 323496fd7ce5SGreg Kroah-Hartman * Returns a pointer to the struct device for this tty device 323596fd7ce5SGreg Kroah-Hartman * (or ERR_PTR(-EFOO) on error). 323696fd7ce5SGreg Kroah-Hartman * 323796fd7ce5SGreg Kroah-Hartman * This call is required to be made to register an individual tty device 323896fd7ce5SGreg Kroah-Hartman * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 323996fd7ce5SGreg Kroah-Hartman * that bit is not set, this function should not be called by a tty 324096fd7ce5SGreg Kroah-Hartman * driver. 324196fd7ce5SGreg Kroah-Hartman * 324296fd7ce5SGreg Kroah-Hartman * Locking: ?? 324396fd7ce5SGreg Kroah-Hartman */ 324496fd7ce5SGreg Kroah-Hartman 324596fd7ce5SGreg Kroah-Hartman struct device *tty_register_device(struct tty_driver *driver, unsigned index, 324696fd7ce5SGreg Kroah-Hartman struct device *device) 324796fd7ce5SGreg Kroah-Hartman { 32486915c0e4STomas Hlavacek return tty_register_device_attr(driver, index, device, NULL, NULL); 32496915c0e4STomas Hlavacek } 32506915c0e4STomas Hlavacek EXPORT_SYMBOL(tty_register_device); 32516915c0e4STomas Hlavacek 3252b1b79916STomas Hlavacek static void tty_device_create_release(struct device *dev) 3253b1b79916STomas Hlavacek { 325483db1df4SPeter Hurley dev_dbg(dev, "releasing...\n"); 3255b1b79916STomas Hlavacek kfree(dev); 3256b1b79916STomas Hlavacek } 3257b1b79916STomas Hlavacek 32586915c0e4STomas Hlavacek /** 32596915c0e4STomas Hlavacek * tty_register_device_attr - register a tty device 32606915c0e4STomas Hlavacek * @driver: the tty driver that describes the tty device 32616915c0e4STomas Hlavacek * @index: the index in the tty driver for this tty device 32626915c0e4STomas Hlavacek * @device: a struct device that is associated with this tty device. 32636915c0e4STomas Hlavacek * This field is optional, if there is no known struct device 32646915c0e4STomas Hlavacek * for this tty device it can be set to NULL safely. 32656915c0e4STomas Hlavacek * @drvdata: Driver data to be set to device. 32666915c0e4STomas Hlavacek * @attr_grp: Attribute group to be set on device. 32676915c0e4STomas Hlavacek * 32686915c0e4STomas Hlavacek * Returns a pointer to the struct device for this tty device 32696915c0e4STomas Hlavacek * (or ERR_PTR(-EFOO) on error). 32706915c0e4STomas Hlavacek * 32716915c0e4STomas Hlavacek * This call is required to be made to register an individual tty device 32726915c0e4STomas Hlavacek * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 32736915c0e4STomas Hlavacek * that bit is not set, this function should not be called by a tty 32746915c0e4STomas Hlavacek * driver. 32756915c0e4STomas Hlavacek * 32766915c0e4STomas Hlavacek * Locking: ?? 32776915c0e4STomas Hlavacek */ 32786915c0e4STomas Hlavacek struct device *tty_register_device_attr(struct tty_driver *driver, 32796915c0e4STomas Hlavacek unsigned index, struct device *device, 32806915c0e4STomas Hlavacek void *drvdata, 32816915c0e4STomas Hlavacek const struct attribute_group **attr_grp) 32826915c0e4STomas Hlavacek { 328396fd7ce5SGreg Kroah-Hartman char name[64]; 32846915c0e4STomas Hlavacek dev_t devt = MKDEV(driver->major, driver->minor_start) + index; 32856915c0e4STomas Hlavacek struct device *dev = NULL; 32866915c0e4STomas Hlavacek int retval = -ENODEV; 32877e73eca6SJiri Slaby bool cdev = false; 328896fd7ce5SGreg Kroah-Hartman 328996fd7ce5SGreg Kroah-Hartman if (index >= driver->num) { 3290656fb867SPeter Hurley pr_err("%s: Attempt to register invalid tty line number (%d)\n", 3291656fb867SPeter Hurley driver->name, index); 329296fd7ce5SGreg Kroah-Hartman return ERR_PTR(-EINVAL); 329396fd7ce5SGreg Kroah-Hartman } 329496fd7ce5SGreg Kroah-Hartman 329596fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY) 329696fd7ce5SGreg Kroah-Hartman pty_line_name(driver, index, name); 329796fd7ce5SGreg Kroah-Hartman else 329896fd7ce5SGreg Kroah-Hartman tty_line_name(driver, index, name); 329996fd7ce5SGreg Kroah-Hartman 33007e73eca6SJiri Slaby if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 33016915c0e4STomas Hlavacek retval = tty_cdev_add(driver, devt, index, 1); 33026915c0e4STomas Hlavacek if (retval) 33036915c0e4STomas Hlavacek goto error; 33047e73eca6SJiri Slaby cdev = true; 33057e73eca6SJiri Slaby } 33067e73eca6SJiri Slaby 33076915c0e4STomas Hlavacek dev = kzalloc(sizeof(*dev), GFP_KERNEL); 33086915c0e4STomas Hlavacek if (!dev) { 33096915c0e4STomas Hlavacek retval = -ENOMEM; 33106915c0e4STomas Hlavacek goto error; 331196fd7ce5SGreg Kroah-Hartman } 33126915c0e4STomas Hlavacek 33136915c0e4STomas Hlavacek dev->devt = devt; 33146915c0e4STomas Hlavacek dev->class = tty_class; 33156915c0e4STomas Hlavacek dev->parent = device; 3316b1b79916STomas Hlavacek dev->release = tty_device_create_release; 33176915c0e4STomas Hlavacek dev_set_name(dev, "%s", name); 33186915c0e4STomas Hlavacek dev->groups = attr_grp; 33196915c0e4STomas Hlavacek dev_set_drvdata(dev, drvdata); 33206915c0e4STomas Hlavacek 33216915c0e4STomas Hlavacek retval = device_register(dev); 33226915c0e4STomas Hlavacek if (retval) 33236915c0e4STomas Hlavacek goto error; 33246915c0e4STomas Hlavacek 33256915c0e4STomas Hlavacek return dev; 33266915c0e4STomas Hlavacek 33276915c0e4STomas Hlavacek error: 33286915c0e4STomas Hlavacek put_device(dev); 3329a3a10ce3SRichard Watts if (cdev) { 3330a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3331a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3332a3a10ce3SRichard Watts } 33336915c0e4STomas Hlavacek return ERR_PTR(retval); 33346915c0e4STomas Hlavacek } 33356915c0e4STomas Hlavacek EXPORT_SYMBOL_GPL(tty_register_device_attr); 333696fd7ce5SGreg Kroah-Hartman 333796fd7ce5SGreg Kroah-Hartman /** 333896fd7ce5SGreg Kroah-Hartman * tty_unregister_device - unregister a tty device 333996fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 334096fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 334196fd7ce5SGreg Kroah-Hartman * 334296fd7ce5SGreg Kroah-Hartman * If a tty device is registered with a call to tty_register_device() then 334396fd7ce5SGreg Kroah-Hartman * this function must be called when the tty device is gone. 334496fd7ce5SGreg Kroah-Hartman * 334596fd7ce5SGreg Kroah-Hartman * Locking: ?? 334696fd7ce5SGreg Kroah-Hartman */ 334796fd7ce5SGreg Kroah-Hartman 334896fd7ce5SGreg Kroah-Hartman void tty_unregister_device(struct tty_driver *driver, unsigned index) 334996fd7ce5SGreg Kroah-Hartman { 335096fd7ce5SGreg Kroah-Hartman device_destroy(tty_class, 335196fd7ce5SGreg Kroah-Hartman MKDEV(driver->major, driver->minor_start) + index); 3352a3a10ce3SRichard Watts if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 3353a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3354a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3355a3a10ce3SRichard Watts } 335696fd7ce5SGreg Kroah-Hartman } 335796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_device); 335896fd7ce5SGreg Kroah-Hartman 33597f0bc6a6SJiri Slaby /** 33607f0bc6a6SJiri Slaby * __tty_alloc_driver -- allocate tty driver 33617f0bc6a6SJiri Slaby * @lines: count of lines this driver can handle at most 33627f0bc6a6SJiri Slaby * @owner: module which is repsonsible for this driver 33637f0bc6a6SJiri Slaby * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags 33647f0bc6a6SJiri Slaby * 33657f0bc6a6SJiri Slaby * This should not be called directly, some of the provided macros should be 33667f0bc6a6SJiri Slaby * used instead. Use IS_ERR and friends on @retval. 33677f0bc6a6SJiri Slaby */ 33687f0bc6a6SJiri Slaby struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner, 33697f0bc6a6SJiri Slaby unsigned long flags) 337096fd7ce5SGreg Kroah-Hartman { 337196fd7ce5SGreg Kroah-Hartman struct tty_driver *driver; 33727e73eca6SJiri Slaby unsigned int cdevs = 1; 337316a02081SJiri Slaby int err; 337496fd7ce5SGreg Kroah-Hartman 33750019b408SJiri Slaby if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1)) 33767f0bc6a6SJiri Slaby return ERR_PTR(-EINVAL); 33777f0bc6a6SJiri Slaby 337896fd7ce5SGreg Kroah-Hartman driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); 33797f0bc6a6SJiri Slaby if (!driver) 33807f0bc6a6SJiri Slaby return ERR_PTR(-ENOMEM); 33817f0bc6a6SJiri Slaby 338296fd7ce5SGreg Kroah-Hartman kref_init(&driver->kref); 338396fd7ce5SGreg Kroah-Hartman driver->magic = TTY_DRIVER_MAGIC; 338496fd7ce5SGreg Kroah-Hartman driver->num = lines; 33851a54a76dSJiri Slaby driver->owner = owner; 33867f0bc6a6SJiri Slaby driver->flags = flags; 338716a02081SJiri Slaby 338816a02081SJiri Slaby if (!(flags & TTY_DRIVER_DEVPTS_MEM)) { 338916a02081SJiri Slaby driver->ttys = kcalloc(lines, sizeof(*driver->ttys), 339016a02081SJiri Slaby GFP_KERNEL); 339116a02081SJiri Slaby driver->termios = kcalloc(lines, sizeof(*driver->termios), 339216a02081SJiri Slaby GFP_KERNEL); 339316a02081SJiri Slaby if (!driver->ttys || !driver->termios) { 339416a02081SJiri Slaby err = -ENOMEM; 339516a02081SJiri Slaby goto err_free_all; 339616a02081SJiri Slaby } 339716a02081SJiri Slaby } 339816a02081SJiri Slaby 339916a02081SJiri Slaby if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 340016a02081SJiri Slaby driver->ports = kcalloc(lines, sizeof(*driver->ports), 340116a02081SJiri Slaby GFP_KERNEL); 340216a02081SJiri Slaby if (!driver->ports) { 340316a02081SJiri Slaby err = -ENOMEM; 340416a02081SJiri Slaby goto err_free_all; 340516a02081SJiri Slaby } 34067e73eca6SJiri Slaby cdevs = lines; 34077e73eca6SJiri Slaby } 34087e73eca6SJiri Slaby 34097e73eca6SJiri Slaby driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL); 34107e73eca6SJiri Slaby if (!driver->cdevs) { 34117e73eca6SJiri Slaby err = -ENOMEM; 34127e73eca6SJiri Slaby goto err_free_all; 341316a02081SJiri Slaby } 34147f0bc6a6SJiri Slaby 341596fd7ce5SGreg Kroah-Hartman return driver; 341616a02081SJiri Slaby err_free_all: 341716a02081SJiri Slaby kfree(driver->ports); 341816a02081SJiri Slaby kfree(driver->ttys); 341916a02081SJiri Slaby kfree(driver->termios); 3420a3a10ce3SRichard Watts kfree(driver->cdevs); 342116a02081SJiri Slaby kfree(driver); 342216a02081SJiri Slaby return ERR_PTR(err); 342396fd7ce5SGreg Kroah-Hartman } 34247f0bc6a6SJiri Slaby EXPORT_SYMBOL(__tty_alloc_driver); 342596fd7ce5SGreg Kroah-Hartman 342696fd7ce5SGreg Kroah-Hartman static void destruct_tty_driver(struct kref *kref) 342796fd7ce5SGreg Kroah-Hartman { 342896fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = container_of(kref, struct tty_driver, kref); 342996fd7ce5SGreg Kroah-Hartman int i; 343096fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 343196fd7ce5SGreg Kroah-Hartman 343296fd7ce5SGreg Kroah-Hartman if (driver->flags & TTY_DRIVER_INSTALLED) { 343396fd7ce5SGreg Kroah-Hartman /* 343496fd7ce5SGreg Kroah-Hartman * Free the termios and termios_locked structures because 343596fd7ce5SGreg Kroah-Hartman * we don't want to get memory leaks when modular tty 343696fd7ce5SGreg Kroah-Hartman * drivers are removed from the kernel. 343796fd7ce5SGreg Kroah-Hartman */ 343896fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 343996fd7ce5SGreg Kroah-Hartman tp = driver->termios[i]; 344096fd7ce5SGreg Kroah-Hartman if (tp) { 344196fd7ce5SGreg Kroah-Hartman driver->termios[i] = NULL; 344296fd7ce5SGreg Kroah-Hartman kfree(tp); 344396fd7ce5SGreg Kroah-Hartman } 344496fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) 344596fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 344696fd7ce5SGreg Kroah-Hartman } 344796fd7ce5SGreg Kroah-Hartman proc_tty_unregister_driver(driver); 34487e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) 3449a3a10ce3SRichard Watts cdev_del(driver->cdevs[0]); 345096fd7ce5SGreg Kroah-Hartman } 34517e73eca6SJiri Slaby kfree(driver->cdevs); 345204831dc1SJiri Slaby kfree(driver->ports); 345316a02081SJiri Slaby kfree(driver->termios); 345416a02081SJiri Slaby kfree(driver->ttys); 345596fd7ce5SGreg Kroah-Hartman kfree(driver); 345696fd7ce5SGreg Kroah-Hartman } 345796fd7ce5SGreg Kroah-Hartman 345896fd7ce5SGreg Kroah-Hartman void tty_driver_kref_put(struct tty_driver *driver) 345996fd7ce5SGreg Kroah-Hartman { 346096fd7ce5SGreg Kroah-Hartman kref_put(&driver->kref, destruct_tty_driver); 346196fd7ce5SGreg Kroah-Hartman } 346296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_driver_kref_put); 346396fd7ce5SGreg Kroah-Hartman 346496fd7ce5SGreg Kroah-Hartman void tty_set_operations(struct tty_driver *driver, 346596fd7ce5SGreg Kroah-Hartman const struct tty_operations *op) 346696fd7ce5SGreg Kroah-Hartman { 346796fd7ce5SGreg Kroah-Hartman driver->ops = op; 346896fd7ce5SGreg Kroah-Hartman }; 346996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_set_operations); 347096fd7ce5SGreg Kroah-Hartman 347196fd7ce5SGreg Kroah-Hartman void put_tty_driver(struct tty_driver *d) 347296fd7ce5SGreg Kroah-Hartman { 347396fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(d); 347496fd7ce5SGreg Kroah-Hartman } 347596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(put_tty_driver); 347696fd7ce5SGreg Kroah-Hartman 347796fd7ce5SGreg Kroah-Hartman /* 347896fd7ce5SGreg Kroah-Hartman * Called by a tty driver to register itself. 347996fd7ce5SGreg Kroah-Hartman */ 348096fd7ce5SGreg Kroah-Hartman int tty_register_driver(struct tty_driver *driver) 348196fd7ce5SGreg Kroah-Hartman { 348296fd7ce5SGreg Kroah-Hartman int error; 348396fd7ce5SGreg Kroah-Hartman int i; 348496fd7ce5SGreg Kroah-Hartman dev_t dev; 348596fd7ce5SGreg Kroah-Hartman struct device *d; 348696fd7ce5SGreg Kroah-Hartman 348796fd7ce5SGreg Kroah-Hartman if (!driver->major) { 348896fd7ce5SGreg Kroah-Hartman error = alloc_chrdev_region(&dev, driver->minor_start, 348996fd7ce5SGreg Kroah-Hartman driver->num, driver->name); 349096fd7ce5SGreg Kroah-Hartman if (!error) { 349196fd7ce5SGreg Kroah-Hartman driver->major = MAJOR(dev); 349296fd7ce5SGreg Kroah-Hartman driver->minor_start = MINOR(dev); 349396fd7ce5SGreg Kroah-Hartman } 349496fd7ce5SGreg Kroah-Hartman } else { 349596fd7ce5SGreg Kroah-Hartman dev = MKDEV(driver->major, driver->minor_start); 349696fd7ce5SGreg Kroah-Hartman error = register_chrdev_region(dev, driver->num, driver->name); 349796fd7ce5SGreg Kroah-Hartman } 34989bb8a3d4SJiri Slaby if (error < 0) 349916a02081SJiri Slaby goto err; 350096fd7ce5SGreg Kroah-Hartman 35017e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) { 35027e73eca6SJiri Slaby error = tty_cdev_add(driver, dev, 0, driver->num); 35039bb8a3d4SJiri Slaby if (error) 35049bb8a3d4SJiri Slaby goto err_unreg_char; 35057e73eca6SJiri Slaby } 350696fd7ce5SGreg Kroah-Hartman 350796fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 350896fd7ce5SGreg Kroah-Hartman list_add(&driver->tty_drivers, &tty_drivers); 350996fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 351096fd7ce5SGreg Kroah-Hartman 351196fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { 351296fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 351396fd7ce5SGreg Kroah-Hartman d = tty_register_device(driver, i, NULL); 351496fd7ce5SGreg Kroah-Hartman if (IS_ERR(d)) { 351596fd7ce5SGreg Kroah-Hartman error = PTR_ERR(d); 351616a02081SJiri Slaby goto err_unreg_devs; 351796fd7ce5SGreg Kroah-Hartman } 351896fd7ce5SGreg Kroah-Hartman } 351996fd7ce5SGreg Kroah-Hartman } 352096fd7ce5SGreg Kroah-Hartman proc_tty_register_driver(driver); 352196fd7ce5SGreg Kroah-Hartman driver->flags |= TTY_DRIVER_INSTALLED; 352296fd7ce5SGreg Kroah-Hartman return 0; 352396fd7ce5SGreg Kroah-Hartman 352416a02081SJiri Slaby err_unreg_devs: 352596fd7ce5SGreg Kroah-Hartman for (i--; i >= 0; i--) 352696fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 352796fd7ce5SGreg Kroah-Hartman 352896fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 352996fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 353096fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 353196fd7ce5SGreg Kroah-Hartman 35329bb8a3d4SJiri Slaby err_unreg_char: 353396fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(dev, driver->num); 353416a02081SJiri Slaby err: 353596fd7ce5SGreg Kroah-Hartman return error; 353696fd7ce5SGreg Kroah-Hartman } 353796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_register_driver); 353896fd7ce5SGreg Kroah-Hartman 353996fd7ce5SGreg Kroah-Hartman /* 354096fd7ce5SGreg Kroah-Hartman * Called by a tty driver to unregister itself. 354196fd7ce5SGreg Kroah-Hartman */ 354296fd7ce5SGreg Kroah-Hartman int tty_unregister_driver(struct tty_driver *driver) 354396fd7ce5SGreg Kroah-Hartman { 354496fd7ce5SGreg Kroah-Hartman #if 0 354596fd7ce5SGreg Kroah-Hartman /* FIXME */ 354696fd7ce5SGreg Kroah-Hartman if (driver->refcount) 354796fd7ce5SGreg Kroah-Hartman return -EBUSY; 354896fd7ce5SGreg Kroah-Hartman #endif 354996fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), 355096fd7ce5SGreg Kroah-Hartman driver->num); 355196fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 355296fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 355396fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 355496fd7ce5SGreg Kroah-Hartman return 0; 355596fd7ce5SGreg Kroah-Hartman } 355696fd7ce5SGreg Kroah-Hartman 355796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_driver); 355896fd7ce5SGreg Kroah-Hartman 355996fd7ce5SGreg Kroah-Hartman dev_t tty_devnum(struct tty_struct *tty) 356096fd7ce5SGreg Kroah-Hartman { 356196fd7ce5SGreg Kroah-Hartman return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; 356296fd7ce5SGreg Kroah-Hartman } 356396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_devnum); 356496fd7ce5SGreg Kroah-Hartman 356596fd7ce5SGreg Kroah-Hartman void tty_default_fops(struct file_operations *fops) 356696fd7ce5SGreg Kroah-Hartman { 356796fd7ce5SGreg Kroah-Hartman *fops = tty_fops; 356896fd7ce5SGreg Kroah-Hartman } 356996fd7ce5SGreg Kroah-Hartman 357096fd7ce5SGreg Kroah-Hartman /* 357196fd7ce5SGreg Kroah-Hartman * Initialize the console device. This is called *early*, so 357296fd7ce5SGreg Kroah-Hartman * we can't necessarily depend on lots of kernel help here. 357396fd7ce5SGreg Kroah-Hartman * Just do some early initializations, and do the complex setup 357496fd7ce5SGreg Kroah-Hartman * later. 357596fd7ce5SGreg Kroah-Hartman */ 357696fd7ce5SGreg Kroah-Hartman void __init console_init(void) 357796fd7ce5SGreg Kroah-Hartman { 357896fd7ce5SGreg Kroah-Hartman initcall_t *call; 357996fd7ce5SGreg Kroah-Hartman 358096fd7ce5SGreg Kroah-Hartman /* Setup the default TTY line discipline. */ 358127228732SPeter Hurley n_tty_init(); 358296fd7ce5SGreg Kroah-Hartman 358396fd7ce5SGreg Kroah-Hartman /* 358496fd7ce5SGreg Kroah-Hartman * set up the console device so that later boot sequences can 358596fd7ce5SGreg Kroah-Hartman * inform about problems etc.. 358696fd7ce5SGreg Kroah-Hartman */ 358796fd7ce5SGreg Kroah-Hartman call = __con_initcall_start; 358896fd7ce5SGreg Kroah-Hartman while (call < __con_initcall_end) { 358996fd7ce5SGreg Kroah-Hartman (*call)(); 359096fd7ce5SGreg Kroah-Hartman call++; 359196fd7ce5SGreg Kroah-Hartman } 359296fd7ce5SGreg Kroah-Hartman } 359396fd7ce5SGreg Kroah-Hartman 35942c9ede55SAl Viro static char *tty_devnode(struct device *dev, umode_t *mode) 359596fd7ce5SGreg Kroah-Hartman { 359696fd7ce5SGreg Kroah-Hartman if (!mode) 359796fd7ce5SGreg Kroah-Hartman return NULL; 359896fd7ce5SGreg Kroah-Hartman if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || 359996fd7ce5SGreg Kroah-Hartman dev->devt == MKDEV(TTYAUX_MAJOR, 2)) 360096fd7ce5SGreg Kroah-Hartman *mode = 0666; 360196fd7ce5SGreg Kroah-Hartman return NULL; 360296fd7ce5SGreg Kroah-Hartman } 360396fd7ce5SGreg Kroah-Hartman 360496fd7ce5SGreg Kroah-Hartman static int __init tty_class_init(void) 360596fd7ce5SGreg Kroah-Hartman { 360696fd7ce5SGreg Kroah-Hartman tty_class = class_create(THIS_MODULE, "tty"); 360796fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty_class)) 360896fd7ce5SGreg Kroah-Hartman return PTR_ERR(tty_class); 360996fd7ce5SGreg Kroah-Hartman tty_class->devnode = tty_devnode; 361096fd7ce5SGreg Kroah-Hartman return 0; 361196fd7ce5SGreg Kroah-Hartman } 361296fd7ce5SGreg Kroah-Hartman 361396fd7ce5SGreg Kroah-Hartman postcore_initcall(tty_class_init); 361496fd7ce5SGreg Kroah-Hartman 361596fd7ce5SGreg Kroah-Hartman /* 3/2004 jmc: why do these devices exist? */ 361696fd7ce5SGreg Kroah-Hartman static struct cdev tty_cdev, console_cdev; 361796fd7ce5SGreg Kroah-Hartman 3618fbc92a34SKay Sievers static ssize_t show_cons_active(struct device *dev, 3619fbc92a34SKay Sievers struct device_attribute *attr, char *buf) 3620fbc92a34SKay Sievers { 3621fbc92a34SKay Sievers struct console *cs[16]; 3622fbc92a34SKay Sievers int i = 0; 3623fbc92a34SKay Sievers struct console *c; 3624fbc92a34SKay Sievers ssize_t count = 0; 3625fbc92a34SKay Sievers 3626ac751efaSTorben Hohn console_lock(); 3627a2a6a822SKay Sievers for_each_console(c) { 3628fbc92a34SKay Sievers if (!c->device) 3629fbc92a34SKay Sievers continue; 3630fbc92a34SKay Sievers if (!c->write) 3631fbc92a34SKay Sievers continue; 3632fbc92a34SKay Sievers if ((c->flags & CON_ENABLED) == 0) 3633fbc92a34SKay Sievers continue; 3634fbc92a34SKay Sievers cs[i++] = c; 3635fbc92a34SKay Sievers if (i >= ARRAY_SIZE(cs)) 3636fbc92a34SKay Sievers break; 3637fbc92a34SKay Sievers } 3638723abd87SHannes Reinecke while (i--) { 3639723abd87SHannes Reinecke int index = cs[i]->index; 3640723abd87SHannes Reinecke struct tty_driver *drv = cs[i]->device(cs[i], &index); 3641723abd87SHannes Reinecke 3642723abd87SHannes Reinecke /* don't resolve tty0 as some programs depend on it */ 3643723abd87SHannes Reinecke if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR)) 3644723abd87SHannes Reinecke count += tty_line_name(drv, index, buf + count); 3645723abd87SHannes Reinecke else 3646723abd87SHannes Reinecke count += sprintf(buf + count, "%s%d", 3647723abd87SHannes Reinecke cs[i]->name, cs[i]->index); 3648723abd87SHannes Reinecke 3649723abd87SHannes Reinecke count += sprintf(buf + count, "%c", i ? ' ':'\n'); 3650723abd87SHannes Reinecke } 3651ac751efaSTorben Hohn console_unlock(); 3652fbc92a34SKay Sievers 3653fbc92a34SKay Sievers return count; 3654fbc92a34SKay Sievers } 3655fbc92a34SKay Sievers static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL); 3656fbc92a34SKay Sievers 36571083a7beSTakashi Iwai static struct attribute *cons_dev_attrs[] = { 36581083a7beSTakashi Iwai &dev_attr_active.attr, 36591083a7beSTakashi Iwai NULL 36601083a7beSTakashi Iwai }; 36611083a7beSTakashi Iwai 36621083a7beSTakashi Iwai ATTRIBUTE_GROUPS(cons_dev); 36631083a7beSTakashi Iwai 3664fbc92a34SKay Sievers static struct device *consdev; 3665fbc92a34SKay Sievers 3666fbc92a34SKay Sievers void console_sysfs_notify(void) 3667fbc92a34SKay Sievers { 3668fbc92a34SKay Sievers if (consdev) 3669fbc92a34SKay Sievers sysfs_notify(&consdev->kobj, NULL, "active"); 3670fbc92a34SKay Sievers } 3671fbc92a34SKay Sievers 367296fd7ce5SGreg Kroah-Hartman /* 367396fd7ce5SGreg Kroah-Hartman * Ok, now we can initialize the rest of the tty devices and can count 367496fd7ce5SGreg Kroah-Hartman * on memory allocations, interrupts etc.. 367596fd7ce5SGreg Kroah-Hartman */ 367696fd7ce5SGreg Kroah-Hartman int __init tty_init(void) 367796fd7ce5SGreg Kroah-Hartman { 367896fd7ce5SGreg Kroah-Hartman cdev_init(&tty_cdev, &tty_fops); 367996fd7ce5SGreg Kroah-Hartman if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || 368096fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) 368196fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/tty driver\n"); 3682fbc92a34SKay Sievers device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty"); 368396fd7ce5SGreg Kroah-Hartman 368496fd7ce5SGreg Kroah-Hartman cdev_init(&console_cdev, &console_fops); 368596fd7ce5SGreg Kroah-Hartman if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || 368696fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) 368796fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/console driver\n"); 36881083a7beSTakashi Iwai consdev = device_create_with_groups(tty_class, NULL, 36891083a7beSTakashi Iwai MKDEV(TTYAUX_MAJOR, 1), NULL, 36901083a7beSTakashi Iwai cons_dev_groups, "console"); 3691fbc92a34SKay Sievers if (IS_ERR(consdev)) 3692fbc92a34SKay Sievers consdev = NULL; 369396fd7ce5SGreg Kroah-Hartman 369496fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_VT 369596fd7ce5SGreg Kroah-Hartman vty_init(&console_fops); 369696fd7ce5SGreg Kroah-Hartman #endif 369796fd7ce5SGreg Kroah-Hartman return 0; 369896fd7ce5SGreg Kroah-Hartman } 369996fd7ce5SGreg Kroah-Hartman 3700