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, 12696fd7ce5SGreg Kroah-Hartman .c_ospeed = 38400 12796fd7ce5SGreg Kroah-Hartman }; 12896fd7ce5SGreg Kroah-Hartman 12996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_std_termios); 13096fd7ce5SGreg Kroah-Hartman 13196fd7ce5SGreg Kroah-Hartman /* This list gets poked at by procfs and various bits of boot up code. This 13296fd7ce5SGreg Kroah-Hartman could do with some rationalisation such as pulling the tty proc function 13396fd7ce5SGreg Kroah-Hartman into this file */ 13496fd7ce5SGreg Kroah-Hartman 13596fd7ce5SGreg Kroah-Hartman LIST_HEAD(tty_drivers); /* linked list of tty drivers */ 13696fd7ce5SGreg Kroah-Hartman 13796fd7ce5SGreg Kroah-Hartman /* Mutex to protect creating and releasing a tty. This is shared with 13896fd7ce5SGreg Kroah-Hartman vt.c for deeply disgusting hack reasons */ 13996fd7ce5SGreg Kroah-Hartman DEFINE_MUTEX(tty_mutex); 14096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_mutex); 14196fd7ce5SGreg Kroah-Hartman 14296fd7ce5SGreg Kroah-Hartman /* Spinlock to protect the tty->tty_files list */ 14396fd7ce5SGreg Kroah-Hartman DEFINE_SPINLOCK(tty_files_lock); 14496fd7ce5SGreg Kroah-Hartman 14596fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); 14696fd7ce5SGreg Kroah-Hartman static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *); 14796fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *, const char __user *, 14896fd7ce5SGreg Kroah-Hartman size_t, loff_t *); 14996fd7ce5SGreg Kroah-Hartman static unsigned int tty_poll(struct file *, poll_table *); 15096fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *, struct file *); 15196fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 15296fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 15396fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 15496fd7ce5SGreg Kroah-Hartman unsigned long arg); 15596fd7ce5SGreg Kroah-Hartman #else 15696fd7ce5SGreg Kroah-Hartman #define tty_compat_ioctl NULL 15796fd7ce5SGreg Kroah-Hartman #endif 15896fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on); 15996fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on); 16096fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx); 16196fd7ce5SGreg Kroah-Hartman 16296fd7ce5SGreg Kroah-Hartman /** 16396fd7ce5SGreg Kroah-Hartman * free_tty_struct - free a disused tty 16496fd7ce5SGreg Kroah-Hartman * @tty: tty struct to free 16596fd7ce5SGreg Kroah-Hartman * 16696fd7ce5SGreg Kroah-Hartman * Free the write buffers, tty queue and tty memory itself. 16796fd7ce5SGreg Kroah-Hartman * 16896fd7ce5SGreg Kroah-Hartman * Locking: none. Must be called after tty is definitely unused 16996fd7ce5SGreg Kroah-Hartman */ 17096fd7ce5SGreg Kroah-Hartman 17196fd7ce5SGreg Kroah-Hartman void free_tty_struct(struct tty_struct *tty) 17296fd7ce5SGreg Kroah-Hartman { 173dc6802a7SDan Carpenter if (!tty) 174dc6802a7SDan Carpenter return; 17596fd7ce5SGreg Kroah-Hartman put_device(tty->dev); 17696fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 17789c8d91eSAlan Cox tty->magic = 0xDEADDEAD; 17896fd7ce5SGreg Kroah-Hartman kfree(tty); 17996fd7ce5SGreg Kroah-Hartman } 18096fd7ce5SGreg Kroah-Hartman 18196fd7ce5SGreg Kroah-Hartman static inline struct tty_struct *file_tty(struct file *file) 18296fd7ce5SGreg Kroah-Hartman { 18396fd7ce5SGreg Kroah-Hartman return ((struct tty_file_private *)file->private_data)->tty; 18496fd7ce5SGreg Kroah-Hartman } 18596fd7ce5SGreg Kroah-Hartman 186fa90e1c9SJiri Slaby int tty_alloc_file(struct file *file) 18796fd7ce5SGreg Kroah-Hartman { 18896fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 18996fd7ce5SGreg Kroah-Hartman 19096fd7ce5SGreg Kroah-Hartman priv = kmalloc(sizeof(*priv), GFP_KERNEL); 19196fd7ce5SGreg Kroah-Hartman if (!priv) 19296fd7ce5SGreg Kroah-Hartman return -ENOMEM; 19396fd7ce5SGreg Kroah-Hartman 194fa90e1c9SJiri Slaby file->private_data = priv; 195fa90e1c9SJiri Slaby 196fa90e1c9SJiri Slaby return 0; 197fa90e1c9SJiri Slaby } 198fa90e1c9SJiri Slaby 199fa90e1c9SJiri Slaby /* Associate a new file with the tty structure */ 200fa90e1c9SJiri Slaby void tty_add_file(struct tty_struct *tty, struct file *file) 201fa90e1c9SJiri Slaby { 202fa90e1c9SJiri Slaby struct tty_file_private *priv = file->private_data; 203fa90e1c9SJiri Slaby 20496fd7ce5SGreg Kroah-Hartman priv->tty = tty; 20596fd7ce5SGreg Kroah-Hartman priv->file = file; 20696fd7ce5SGreg Kroah-Hartman 20796fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 20896fd7ce5SGreg Kroah-Hartman list_add(&priv->list, &tty->tty_files); 20996fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 210fa90e1c9SJiri Slaby } 21196fd7ce5SGreg Kroah-Hartman 212fa90e1c9SJiri Slaby /** 213fa90e1c9SJiri Slaby * tty_free_file - free file->private_data 214fa90e1c9SJiri Slaby * 215fa90e1c9SJiri Slaby * This shall be used only for fail path handling when tty_add_file was not 216fa90e1c9SJiri Slaby * called yet. 217fa90e1c9SJiri Slaby */ 218fa90e1c9SJiri Slaby void tty_free_file(struct file *file) 219fa90e1c9SJiri Slaby { 220fa90e1c9SJiri Slaby struct tty_file_private *priv = file->private_data; 221fa90e1c9SJiri Slaby 222fa90e1c9SJiri Slaby file->private_data = NULL; 223fa90e1c9SJiri Slaby kfree(priv); 22496fd7ce5SGreg Kroah-Hartman } 22596fd7ce5SGreg Kroah-Hartman 22696fd7ce5SGreg Kroah-Hartman /* Delete file from its tty */ 2272520e274SJosh Triplett static void tty_del_file(struct file *file) 22896fd7ce5SGreg Kroah-Hartman { 22996fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv = file->private_data; 23096fd7ce5SGreg Kroah-Hartman 23196fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 23296fd7ce5SGreg Kroah-Hartman list_del(&priv->list); 23396fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 234fa90e1c9SJiri Slaby tty_free_file(file); 23596fd7ce5SGreg Kroah-Hartman } 23696fd7ce5SGreg Kroah-Hartman 23796fd7ce5SGreg Kroah-Hartman 23896fd7ce5SGreg Kroah-Hartman #define TTY_NUMBER(tty) ((tty)->index + (tty)->driver->name_base) 23996fd7ce5SGreg Kroah-Hartman 24096fd7ce5SGreg Kroah-Hartman /** 24196fd7ce5SGreg Kroah-Hartman * tty_name - return tty naming 24296fd7ce5SGreg Kroah-Hartman * @tty: tty structure 24396fd7ce5SGreg Kroah-Hartman * 24496fd7ce5SGreg Kroah-Hartman * Convert a tty structure into a name. The name reflects the kernel 24596fd7ce5SGreg Kroah-Hartman * naming policy and if udev is in use may not reflect user space 24696fd7ce5SGreg Kroah-Hartman * 24796fd7ce5SGreg Kroah-Hartman * Locking: none 24896fd7ce5SGreg Kroah-Hartman */ 24996fd7ce5SGreg Kroah-Hartman 250429b4749SRasmus Villemoes const char *tty_name(const struct tty_struct *tty) 25196fd7ce5SGreg Kroah-Hartman { 25296fd7ce5SGreg Kroah-Hartman if (!tty) /* Hmm. NULL pointer. That's fun. */ 253917162c9SRasmus Villemoes return "NULL tty"; 254917162c9SRasmus Villemoes return tty->name; 25596fd7ce5SGreg Kroah-Hartman } 25696fd7ce5SGreg Kroah-Hartman 25796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_name); 25896fd7ce5SGreg Kroah-Hartman 2590a083eddSPeter Hurley const char *tty_driver_name(const struct tty_struct *tty) 2600a083eddSPeter Hurley { 2610a083eddSPeter Hurley if (!tty || !tty->driver) 2620a083eddSPeter Hurley return ""; 2630a083eddSPeter Hurley return tty->driver->name; 2640a083eddSPeter Hurley } 2650a083eddSPeter Hurley 26682b8f888SPeter Hurley static int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 26796fd7ce5SGreg Kroah-Hartman const char *routine) 26896fd7ce5SGreg Kroah-Hartman { 26996fd7ce5SGreg Kroah-Hartman #ifdef TTY_PARANOIA_CHECK 27096fd7ce5SGreg Kroah-Hartman if (!tty) { 27189222e62SPeter Hurley pr_warn("(%d:%d): %s: NULL tty\n", 27296fd7ce5SGreg Kroah-Hartman imajor(inode), iminor(inode), routine); 27396fd7ce5SGreg Kroah-Hartman return 1; 27496fd7ce5SGreg Kroah-Hartman } 27596fd7ce5SGreg Kroah-Hartman if (tty->magic != TTY_MAGIC) { 27689222e62SPeter Hurley pr_warn("(%d:%d): %s: bad magic number\n", 27796fd7ce5SGreg Kroah-Hartman imajor(inode), iminor(inode), routine); 27896fd7ce5SGreg Kroah-Hartman return 1; 27996fd7ce5SGreg Kroah-Hartman } 28096fd7ce5SGreg Kroah-Hartman #endif 28196fd7ce5SGreg Kroah-Hartman return 0; 28296fd7ce5SGreg Kroah-Hartman } 28396fd7ce5SGreg Kroah-Hartman 284deb287e7SPeter Hurley /* Caller must hold tty_lock */ 28596fd7ce5SGreg Kroah-Hartman static int check_tty_count(struct tty_struct *tty, const char *routine) 28696fd7ce5SGreg Kroah-Hartman { 28796fd7ce5SGreg Kroah-Hartman #ifdef CHECK_TTY_COUNT 28896fd7ce5SGreg Kroah-Hartman struct list_head *p; 28996fd7ce5SGreg Kroah-Hartman int count = 0; 29096fd7ce5SGreg Kroah-Hartman 29196fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 29296fd7ce5SGreg Kroah-Hartman list_for_each(p, &tty->tty_files) { 29396fd7ce5SGreg Kroah-Hartman count++; 29496fd7ce5SGreg Kroah-Hartman } 29596fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 29696fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 29796fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_SLAVE && 29896fd7ce5SGreg Kroah-Hartman tty->link && tty->link->count) 29996fd7ce5SGreg Kroah-Hartman count++; 30096fd7ce5SGreg Kroah-Hartman if (tty->count != count) { 301339f36baSPeter Hurley tty_warn(tty, "%s: tty->count(%d) != #fd's(%d)\n", 302339f36baSPeter Hurley routine, tty->count, count); 30396fd7ce5SGreg Kroah-Hartman return count; 30496fd7ce5SGreg Kroah-Hartman } 30596fd7ce5SGreg Kroah-Hartman #endif 30696fd7ce5SGreg Kroah-Hartman return 0; 30796fd7ce5SGreg Kroah-Hartman } 30896fd7ce5SGreg Kroah-Hartman 30996fd7ce5SGreg Kroah-Hartman /** 31096fd7ce5SGreg Kroah-Hartman * get_tty_driver - find device of a tty 31196fd7ce5SGreg Kroah-Hartman * @dev_t: device identifier 31296fd7ce5SGreg Kroah-Hartman * @index: returns the index of the tty 31396fd7ce5SGreg Kroah-Hartman * 31496fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a device number 31596fd7ce5SGreg Kroah-Hartman * and also passes back the index number. 31696fd7ce5SGreg Kroah-Hartman * 31796fd7ce5SGreg Kroah-Hartman * Locking: caller must hold tty_mutex 31896fd7ce5SGreg Kroah-Hartman */ 31996fd7ce5SGreg Kroah-Hartman 32096fd7ce5SGreg Kroah-Hartman static struct tty_driver *get_tty_driver(dev_t device, int *index) 32196fd7ce5SGreg Kroah-Hartman { 32296fd7ce5SGreg Kroah-Hartman struct tty_driver *p; 32396fd7ce5SGreg Kroah-Hartman 32496fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 32596fd7ce5SGreg Kroah-Hartman dev_t base = MKDEV(p->major, p->minor_start); 32696fd7ce5SGreg Kroah-Hartman if (device < base || device >= base + p->num) 32796fd7ce5SGreg Kroah-Hartman continue; 32896fd7ce5SGreg Kroah-Hartman *index = device - base; 32996fd7ce5SGreg Kroah-Hartman return tty_driver_kref_get(p); 33096fd7ce5SGreg Kroah-Hartman } 33196fd7ce5SGreg Kroah-Hartman return NULL; 33296fd7ce5SGreg Kroah-Hartman } 33396fd7ce5SGreg Kroah-Hartman 33496fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_CONSOLE_POLL 33596fd7ce5SGreg Kroah-Hartman 33696fd7ce5SGreg Kroah-Hartman /** 33796fd7ce5SGreg Kroah-Hartman * tty_find_polling_driver - find device of a polled tty 33896fd7ce5SGreg Kroah-Hartman * @name: name string to match 33996fd7ce5SGreg Kroah-Hartman * @line: pointer to resulting tty line nr 34096fd7ce5SGreg Kroah-Hartman * 34196fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a name 34296fd7ce5SGreg Kroah-Hartman * and the condition that the tty driver is capable of polled 34396fd7ce5SGreg Kroah-Hartman * operation. 34496fd7ce5SGreg Kroah-Hartman */ 34596fd7ce5SGreg Kroah-Hartman struct tty_driver *tty_find_polling_driver(char *name, int *line) 34696fd7ce5SGreg Kroah-Hartman { 34796fd7ce5SGreg Kroah-Hartman struct tty_driver *p, *res = NULL; 34896fd7ce5SGreg Kroah-Hartman int tty_line = 0; 34996fd7ce5SGreg Kroah-Hartman int len; 35096fd7ce5SGreg Kroah-Hartman char *str, *stp; 35196fd7ce5SGreg Kroah-Hartman 35296fd7ce5SGreg Kroah-Hartman for (str = name; *str; str++) 35396fd7ce5SGreg Kroah-Hartman if ((*str >= '0' && *str <= '9') || *str == ',') 35496fd7ce5SGreg Kroah-Hartman break; 35596fd7ce5SGreg Kroah-Hartman if (!*str) 35696fd7ce5SGreg Kroah-Hartman return NULL; 35796fd7ce5SGreg Kroah-Hartman 35896fd7ce5SGreg Kroah-Hartman len = str - name; 35996fd7ce5SGreg Kroah-Hartman tty_line = simple_strtoul(str, &str, 10); 36096fd7ce5SGreg Kroah-Hartman 36196fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 36296fd7ce5SGreg Kroah-Hartman /* Search through the tty devices to look for a match */ 36396fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 36496fd7ce5SGreg Kroah-Hartman if (strncmp(name, p->name, len) != 0) 36596fd7ce5SGreg Kroah-Hartman continue; 36696fd7ce5SGreg Kroah-Hartman stp = str; 36796fd7ce5SGreg Kroah-Hartman if (*stp == ',') 36896fd7ce5SGreg Kroah-Hartman stp++; 36996fd7ce5SGreg Kroah-Hartman if (*stp == '\0') 37096fd7ce5SGreg Kroah-Hartman stp = NULL; 37196fd7ce5SGreg Kroah-Hartman 37296fd7ce5SGreg Kroah-Hartman if (tty_line >= 0 && tty_line < p->num && p->ops && 37396fd7ce5SGreg Kroah-Hartman p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { 37496fd7ce5SGreg Kroah-Hartman res = tty_driver_kref_get(p); 37596fd7ce5SGreg Kroah-Hartman *line = tty_line; 37696fd7ce5SGreg Kroah-Hartman break; 37796fd7ce5SGreg Kroah-Hartman } 37896fd7ce5SGreg Kroah-Hartman } 37996fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 38096fd7ce5SGreg Kroah-Hartman 38196fd7ce5SGreg Kroah-Hartman return res; 38296fd7ce5SGreg Kroah-Hartman } 38396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_find_polling_driver); 38496fd7ce5SGreg Kroah-Hartman #endif 38596fd7ce5SGreg Kroah-Hartman 38696fd7ce5SGreg Kroah-Hartman /** 38796fd7ce5SGreg Kroah-Hartman * tty_check_change - check for POSIX terminal changes 38896fd7ce5SGreg Kroah-Hartman * @tty: tty to check 38996fd7ce5SGreg Kroah-Hartman * 39096fd7ce5SGreg Kroah-Hartman * If we try to write to, or set the state of, a terminal and we're 39196fd7ce5SGreg Kroah-Hartman * not in the foreground, send a SIGTTOU. If the signal is blocked or 39296fd7ce5SGreg Kroah-Hartman * ignored, go ahead and perform the operation. (POSIX 7.2) 39396fd7ce5SGreg Kroah-Hartman * 39496fd7ce5SGreg Kroah-Hartman * Locking: ctrl_lock 39596fd7ce5SGreg Kroah-Hartman */ 39696fd7ce5SGreg Kroah-Hartman 3972812d9e9SPeter Hurley int __tty_check_change(struct tty_struct *tty, int sig) 39896fd7ce5SGreg Kroah-Hartman { 39996fd7ce5SGreg Kroah-Hartman unsigned long flags; 4002812d9e9SPeter Hurley struct pid *pgrp, *tty_pgrp; 40196fd7ce5SGreg Kroah-Hartman int ret = 0; 40296fd7ce5SGreg Kroah-Hartman 40396fd7ce5SGreg Kroah-Hartman if (current->signal->tty != tty) 40496fd7ce5SGreg Kroah-Hartman return 0; 40596fd7ce5SGreg Kroah-Hartman 4066719693cSPatrick Donnelly rcu_read_lock(); 4076719693cSPatrick Donnelly pgrp = task_pgrp(current); 4086719693cSPatrick Donnelly 40996fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 4102812d9e9SPeter Hurley tty_pgrp = tty->pgrp; 41196fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 4126719693cSPatrick Donnelly 4132812d9e9SPeter Hurley if (tty_pgrp && pgrp != tty->pgrp) { 4142812d9e9SPeter Hurley if (is_ignored(sig)) { 4152812d9e9SPeter Hurley if (sig == SIGTTIN) 41696fd7ce5SGreg Kroah-Hartman ret = -EIO; 4172812d9e9SPeter Hurley } else if (is_current_pgrp_orphaned()) 4182812d9e9SPeter Hurley ret = -EIO; 4192812d9e9SPeter Hurley else { 4202812d9e9SPeter Hurley kill_pgrp(pgrp, sig, 1); 42196fd7ce5SGreg Kroah-Hartman set_thread_flag(TIF_SIGPENDING); 42296fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 4232812d9e9SPeter Hurley } 4242812d9e9SPeter Hurley } 4256719693cSPatrick Donnelly rcu_read_unlock(); 4262812d9e9SPeter Hurley 427339f36baSPeter Hurley if (!tty_pgrp) 428339f36baSPeter Hurley tty_warn(tty, "sig=%d, tty->pgrp == NULL!\n", sig); 4292812d9e9SPeter Hurley 43096fd7ce5SGreg Kroah-Hartman return ret; 43196fd7ce5SGreg Kroah-Hartman } 43296fd7ce5SGreg Kroah-Hartman 4332812d9e9SPeter Hurley int tty_check_change(struct tty_struct *tty) 4342812d9e9SPeter Hurley { 4352812d9e9SPeter Hurley return __tty_check_change(tty, SIGTTOU); 4362812d9e9SPeter Hurley } 43796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_check_change); 43896fd7ce5SGreg Kroah-Hartman 43996fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_read(struct file *file, char __user *buf, 44096fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 44196fd7ce5SGreg Kroah-Hartman { 44296fd7ce5SGreg Kroah-Hartman return 0; 44396fd7ce5SGreg Kroah-Hartman } 44496fd7ce5SGreg Kroah-Hartman 44596fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, 44696fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 44796fd7ce5SGreg Kroah-Hartman { 44896fd7ce5SGreg Kroah-Hartman return -EIO; 44996fd7ce5SGreg Kroah-Hartman } 45096fd7ce5SGreg Kroah-Hartman 45196fd7ce5SGreg Kroah-Hartman /* No kernel lock held - none needed ;) */ 45296fd7ce5SGreg Kroah-Hartman static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait) 45396fd7ce5SGreg Kroah-Hartman { 45496fd7ce5SGreg Kroah-Hartman return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; 45596fd7ce5SGreg Kroah-Hartman } 45696fd7ce5SGreg Kroah-Hartman 45796fd7ce5SGreg Kroah-Hartman static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, 45896fd7ce5SGreg Kroah-Hartman unsigned long arg) 45996fd7ce5SGreg Kroah-Hartman { 46096fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 46196fd7ce5SGreg Kroah-Hartman } 46296fd7ce5SGreg Kroah-Hartman 46396fd7ce5SGreg Kroah-Hartman static long hung_up_tty_compat_ioctl(struct file *file, 46496fd7ce5SGreg Kroah-Hartman unsigned int cmd, unsigned long arg) 46596fd7ce5SGreg Kroah-Hartman { 46696fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 46796fd7ce5SGreg Kroah-Hartman } 46896fd7ce5SGreg Kroah-Hartman 46996fd7ce5SGreg Kroah-Hartman static const struct file_operations tty_fops = { 47096fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 47196fd7ce5SGreg Kroah-Hartman .read = tty_read, 47296fd7ce5SGreg Kroah-Hartman .write = tty_write, 47396fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 47496fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 47596fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 47696fd7ce5SGreg Kroah-Hartman .open = tty_open, 47796fd7ce5SGreg Kroah-Hartman .release = tty_release, 47896fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 47996fd7ce5SGreg Kroah-Hartman }; 48096fd7ce5SGreg Kroah-Hartman 48196fd7ce5SGreg Kroah-Hartman static const struct file_operations console_fops = { 48296fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 48396fd7ce5SGreg Kroah-Hartman .read = tty_read, 48496fd7ce5SGreg Kroah-Hartman .write = redirected_tty_write, 48596fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 48696fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 48796fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 48896fd7ce5SGreg Kroah-Hartman .open = tty_open, 48996fd7ce5SGreg Kroah-Hartman .release = tty_release, 49096fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 49196fd7ce5SGreg Kroah-Hartman }; 49296fd7ce5SGreg Kroah-Hartman 49396fd7ce5SGreg Kroah-Hartman static const struct file_operations hung_up_tty_fops = { 49496fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 49596fd7ce5SGreg Kroah-Hartman .read = hung_up_tty_read, 49696fd7ce5SGreg Kroah-Hartman .write = hung_up_tty_write, 49796fd7ce5SGreg Kroah-Hartman .poll = hung_up_tty_poll, 49896fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = hung_up_tty_ioctl, 49996fd7ce5SGreg Kroah-Hartman .compat_ioctl = hung_up_tty_compat_ioctl, 50096fd7ce5SGreg Kroah-Hartman .release = tty_release, 50196fd7ce5SGreg Kroah-Hartman }; 50296fd7ce5SGreg Kroah-Hartman 50396fd7ce5SGreg Kroah-Hartman static DEFINE_SPINLOCK(redirect_lock); 50496fd7ce5SGreg Kroah-Hartman static struct file *redirect; 50596fd7ce5SGreg Kroah-Hartman 50611d9befdSPeter Hurley 50711d9befdSPeter Hurley void proc_clear_tty(struct task_struct *p) 50811d9befdSPeter Hurley { 50911d9befdSPeter Hurley unsigned long flags; 51011d9befdSPeter Hurley struct tty_struct *tty; 51111d9befdSPeter Hurley spin_lock_irqsave(&p->sighand->siglock, flags); 51211d9befdSPeter Hurley tty = p->signal->tty; 51311d9befdSPeter Hurley p->signal->tty = NULL; 51411d9befdSPeter Hurley spin_unlock_irqrestore(&p->sighand->siglock, flags); 51511d9befdSPeter Hurley tty_kref_put(tty); 51611d9befdSPeter Hurley } 51711d9befdSPeter Hurley 5182c411c11SPeter Hurley /** 5192c411c11SPeter Hurley * proc_set_tty - set the controlling terminal 5202c411c11SPeter Hurley * 5212c411c11SPeter Hurley * Only callable by the session leader and only if it does not already have 5222c411c11SPeter Hurley * a controlling terminal. 5232c411c11SPeter Hurley * 524e218eb32SPeter Hurley * Caller must hold: tty_lock() 525e218eb32SPeter Hurley * a readlock on tasklist_lock 5262c411c11SPeter Hurley * sighand lock 5272c411c11SPeter Hurley */ 528bce65f18SPeter Hurley static void __proc_set_tty(struct tty_struct *tty) 52911d9befdSPeter Hurley { 53011d9befdSPeter Hurley unsigned long flags; 531ae28fa72SPeter Hurley 53211d9befdSPeter Hurley spin_lock_irqsave(&tty->ctrl_lock, flags); 533a361858dSPeter Hurley /* 534a361858dSPeter Hurley * The session and fg pgrp references will be non-NULL if 535a361858dSPeter Hurley * tiocsctty() is stealing the controlling tty 536a361858dSPeter Hurley */ 53711d9befdSPeter Hurley put_pid(tty->session); 53811d9befdSPeter Hurley put_pid(tty->pgrp); 539bce65f18SPeter Hurley tty->pgrp = get_pid(task_pgrp(current)); 54011d9befdSPeter Hurley spin_unlock_irqrestore(&tty->ctrl_lock, flags); 541bce65f18SPeter Hurley tty->session = get_pid(task_session(current)); 542bce65f18SPeter Hurley if (current->signal->tty) { 543e2dfa3d3SPeter Hurley tty_debug(tty, "current tty %s not NULL!!\n", 544e2dfa3d3SPeter Hurley current->signal->tty->name); 545bce65f18SPeter Hurley tty_kref_put(current->signal->tty); 54611d9befdSPeter Hurley } 547bce65f18SPeter Hurley put_pid(current->signal->tty_old_pgrp); 548bce65f18SPeter Hurley current->signal->tty = tty_kref_get(tty); 549bce65f18SPeter Hurley current->signal->tty_old_pgrp = NULL; 55011d9befdSPeter Hurley } 55111d9befdSPeter Hurley 552bce65f18SPeter Hurley static void proc_set_tty(struct tty_struct *tty) 55311d9befdSPeter Hurley { 554bce65f18SPeter Hurley spin_lock_irq(¤t->sighand->siglock); 555bce65f18SPeter Hurley __proc_set_tty(tty); 556bce65f18SPeter Hurley spin_unlock_irq(¤t->sighand->siglock); 55711d9befdSPeter Hurley } 55811d9befdSPeter Hurley 55911d9befdSPeter Hurley struct tty_struct *get_current_tty(void) 56011d9befdSPeter Hurley { 56111d9befdSPeter Hurley struct tty_struct *tty; 56211d9befdSPeter Hurley unsigned long flags; 56311d9befdSPeter Hurley 56411d9befdSPeter Hurley spin_lock_irqsave(¤t->sighand->siglock, flags); 56511d9befdSPeter Hurley tty = tty_kref_get(current->signal->tty); 56611d9befdSPeter Hurley spin_unlock_irqrestore(¤t->sighand->siglock, flags); 56711d9befdSPeter Hurley return tty; 56811d9befdSPeter Hurley } 56911d9befdSPeter Hurley EXPORT_SYMBOL_GPL(get_current_tty); 57011d9befdSPeter Hurley 57111d9befdSPeter Hurley static void session_clear_tty(struct pid *session) 57211d9befdSPeter Hurley { 57311d9befdSPeter Hurley struct task_struct *p; 57411d9befdSPeter Hurley do_each_pid_task(session, PIDTYPE_SID, p) { 57511d9befdSPeter Hurley proc_clear_tty(p); 57611d9befdSPeter Hurley } while_each_pid_task(session, PIDTYPE_SID, p); 57711d9befdSPeter Hurley } 57811d9befdSPeter Hurley 57996fd7ce5SGreg Kroah-Hartman /** 58096fd7ce5SGreg Kroah-Hartman * tty_wakeup - request more data 58196fd7ce5SGreg Kroah-Hartman * @tty: terminal 58296fd7ce5SGreg Kroah-Hartman * 58396fd7ce5SGreg Kroah-Hartman * Internal and external helper for wakeups of tty. This function 58496fd7ce5SGreg Kroah-Hartman * informs the line discipline if present that the driver is ready 58596fd7ce5SGreg Kroah-Hartman * to receive more output data. 58696fd7ce5SGreg Kroah-Hartman */ 58796fd7ce5SGreg Kroah-Hartman 58896fd7ce5SGreg Kroah-Hartman void tty_wakeup(struct tty_struct *tty) 58996fd7ce5SGreg Kroah-Hartman { 59096fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 59196fd7ce5SGreg Kroah-Hartman 59296fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { 59396fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref(tty); 59496fd7ce5SGreg Kroah-Hartman if (ld) { 59596fd7ce5SGreg Kroah-Hartman if (ld->ops->write_wakeup) 59696fd7ce5SGreg Kroah-Hartman ld->ops->write_wakeup(tty); 59796fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 59896fd7ce5SGreg Kroah-Hartman } 59996fd7ce5SGreg Kroah-Hartman } 60096fd7ce5SGreg Kroah-Hartman wake_up_interruptible_poll(&tty->write_wait, POLLOUT); 60196fd7ce5SGreg Kroah-Hartman } 60296fd7ce5SGreg Kroah-Hartman 60396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_wakeup); 60496fd7ce5SGreg Kroah-Hartman 60596fd7ce5SGreg Kroah-Hartman /** 606ea648a47SPeter Hurley * tty_signal_session_leader - sends SIGHUP to session leader 607f91e2590SPeter Hurley * @tty controlling tty 608f91e2590SPeter Hurley * @exit_session if non-zero, signal all foreground group processes 609ea648a47SPeter Hurley * 610f91e2590SPeter Hurley * Send SIGHUP and SIGCONT to the session leader and its process group. 611f91e2590SPeter Hurley * Optionally, signal all processes in the foreground process group. 612ea648a47SPeter Hurley * 613ea648a47SPeter Hurley * Returns the number of processes in the session with this tty 614ea648a47SPeter Hurley * as their controlling terminal. This value is used to drop 615ea648a47SPeter Hurley * tty references for those processes. 616ea648a47SPeter Hurley */ 617f91e2590SPeter Hurley static int tty_signal_session_leader(struct tty_struct *tty, int exit_session) 618ea648a47SPeter Hurley { 619ea648a47SPeter Hurley struct task_struct *p; 620ea648a47SPeter Hurley int refs = 0; 621f91e2590SPeter Hurley struct pid *tty_pgrp = NULL; 622ea648a47SPeter Hurley 623ea648a47SPeter Hurley read_lock(&tasklist_lock); 624ea648a47SPeter Hurley if (tty->session) { 625ea648a47SPeter Hurley do_each_pid_task(tty->session, PIDTYPE_SID, p) { 626ea648a47SPeter Hurley spin_lock_irq(&p->sighand->siglock); 627ea648a47SPeter Hurley if (p->signal->tty == tty) { 628ea648a47SPeter Hurley p->signal->tty = NULL; 629ea648a47SPeter Hurley /* We defer the dereferences outside fo 630ea648a47SPeter Hurley the tasklist lock */ 631ea648a47SPeter Hurley refs++; 632ea648a47SPeter Hurley } 633ea648a47SPeter Hurley if (!p->signal->leader) { 634ea648a47SPeter Hurley spin_unlock_irq(&p->sighand->siglock); 635ea648a47SPeter Hurley continue; 636ea648a47SPeter Hurley } 637ea648a47SPeter Hurley __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); 638ea648a47SPeter Hurley __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); 639ea648a47SPeter Hurley put_pid(p->signal->tty_old_pgrp); /* A noop */ 640bc30c3b2SPeter Hurley spin_lock(&tty->ctrl_lock); 641f91e2590SPeter Hurley tty_pgrp = get_pid(tty->pgrp); 642ea648a47SPeter Hurley if (tty->pgrp) 643ea648a47SPeter Hurley p->signal->tty_old_pgrp = get_pid(tty->pgrp); 644bc30c3b2SPeter Hurley spin_unlock(&tty->ctrl_lock); 645ea648a47SPeter Hurley spin_unlock_irq(&p->sighand->siglock); 646ea648a47SPeter Hurley } while_each_pid_task(tty->session, PIDTYPE_SID, p); 647ea648a47SPeter Hurley } 648ea648a47SPeter Hurley read_unlock(&tasklist_lock); 649ea648a47SPeter Hurley 650f91e2590SPeter Hurley if (tty_pgrp) { 651f91e2590SPeter Hurley if (exit_session) 652f91e2590SPeter Hurley kill_pgrp(tty_pgrp, SIGHUP, exit_session); 653f91e2590SPeter Hurley put_pid(tty_pgrp); 654f91e2590SPeter Hurley } 655f91e2590SPeter Hurley 656ea648a47SPeter Hurley return refs; 657ea648a47SPeter Hurley } 658ea648a47SPeter Hurley 659ea648a47SPeter Hurley /** 66096fd7ce5SGreg Kroah-Hartman * __tty_hangup - actual handler for hangup events 66196fd7ce5SGreg Kroah-Hartman * @work: tty device 66296fd7ce5SGreg Kroah-Hartman * 663ef4f527cSKevin Cernekee * This can be called by a "kworker" kernel thread. That is process 66496fd7ce5SGreg Kroah-Hartman * synchronous but doesn't hold any locks, so we need to make sure we 66596fd7ce5SGreg Kroah-Hartman * have the appropriate locks for what we're doing. 66696fd7ce5SGreg Kroah-Hartman * 66796fd7ce5SGreg Kroah-Hartman * The hangup event clears any pending redirections onto the hung up 66896fd7ce5SGreg Kroah-Hartman * device. It ensures future writes will error and it does the needed 66996fd7ce5SGreg Kroah-Hartman * line discipline hangup and signal delivery. The tty object itself 67096fd7ce5SGreg Kroah-Hartman * remains intact. 67196fd7ce5SGreg Kroah-Hartman * 67296fd7ce5SGreg Kroah-Hartman * Locking: 67396fd7ce5SGreg Kroah-Hartman * BTM 67496fd7ce5SGreg Kroah-Hartman * redirect lock for undoing redirection 67596fd7ce5SGreg Kroah-Hartman * file list lock for manipulating list of ttys 676137084bbSPeter Hurley * tty_ldiscs_lock from called functions 6776a1c0680SPeter Hurley * termios_rwsem resetting termios data 67896fd7ce5SGreg Kroah-Hartman * tasklist_lock to walk task list for hangup event 67996fd7ce5SGreg Kroah-Hartman * ->siglock to protect ->signal/->sighand 68096fd7ce5SGreg Kroah-Hartman */ 681f91e2590SPeter Hurley static void __tty_hangup(struct tty_struct *tty, int exit_session) 68296fd7ce5SGreg Kroah-Hartman { 68396fd7ce5SGreg Kroah-Hartman struct file *cons_filp = NULL; 68496fd7ce5SGreg Kroah-Hartman struct file *filp, *f = NULL; 68596fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 68696fd7ce5SGreg Kroah-Hartman int closecount = 0, n; 687ea648a47SPeter Hurley int refs; 68896fd7ce5SGreg Kroah-Hartman 68996fd7ce5SGreg Kroah-Hartman if (!tty) 69096fd7ce5SGreg Kroah-Hartman return; 69196fd7ce5SGreg Kroah-Hartman 69296fd7ce5SGreg Kroah-Hartman 69396fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 69496fd7ce5SGreg Kroah-Hartman if (redirect && file_tty(redirect) == tty) { 69596fd7ce5SGreg Kroah-Hartman f = redirect; 69696fd7ce5SGreg Kroah-Hartman redirect = NULL; 69796fd7ce5SGreg Kroah-Hartman } 69896fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 69996fd7ce5SGreg Kroah-Hartman 70089c8d91eSAlan Cox tty_lock(tty); 70196fd7ce5SGreg Kroah-Hartman 702cb50e523SPeter Hurley if (test_bit(TTY_HUPPED, &tty->flags)) { 703cb50e523SPeter Hurley tty_unlock(tty); 704cb50e523SPeter Hurley return; 705cb50e523SPeter Hurley } 706cb50e523SPeter Hurley 70796fd7ce5SGreg Kroah-Hartman /* inuse_filps is protected by the single tty lock, 70896fd7ce5SGreg Kroah-Hartman this really needs to change if we want to flush the 70996fd7ce5SGreg Kroah-Hartman workqueue with the lock held */ 71096fd7ce5SGreg Kroah-Hartman check_tty_count(tty, "tty_hangup"); 71196fd7ce5SGreg Kroah-Hartman 71296fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 71396fd7ce5SGreg Kroah-Hartman /* This breaks for file handles being sent over AF_UNIX sockets ? */ 71496fd7ce5SGreg Kroah-Hartman list_for_each_entry(priv, &tty->tty_files, list) { 71596fd7ce5SGreg Kroah-Hartman filp = priv->file; 71696fd7ce5SGreg Kroah-Hartman if (filp->f_op->write == redirected_tty_write) 71796fd7ce5SGreg Kroah-Hartman cons_filp = filp; 71896fd7ce5SGreg Kroah-Hartman if (filp->f_op->write != tty_write) 71996fd7ce5SGreg Kroah-Hartman continue; 72096fd7ce5SGreg Kroah-Hartman closecount++; 72196fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); /* can't block */ 72296fd7ce5SGreg Kroah-Hartman filp->f_op = &hung_up_tty_fops; 72396fd7ce5SGreg Kroah-Hartman } 72496fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 72596fd7ce5SGreg Kroah-Hartman 72625fdf243SPeter Hurley refs = tty_signal_session_leader(tty, exit_session); 72725fdf243SPeter Hurley /* Account for the p->signal references we killed */ 72825fdf243SPeter Hurley while (refs--) 72925fdf243SPeter Hurley tty_kref_put(tty); 73025fdf243SPeter Hurley 73196fd7ce5SGreg Kroah-Hartman tty_ldisc_hangup(tty); 73296fd7ce5SGreg Kroah-Hartman 73320cc225bSPeter Hurley spin_lock_irq(&tty->ctrl_lock); 73496fd7ce5SGreg Kroah-Hartman clear_bit(TTY_THROTTLED, &tty->flags); 73596fd7ce5SGreg Kroah-Hartman clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 73696fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 73796fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 73896fd7ce5SGreg Kroah-Hartman tty->session = NULL; 73996fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 74096fd7ce5SGreg Kroah-Hartman tty->ctrl_status = 0; 74120cc225bSPeter Hurley spin_unlock_irq(&tty->ctrl_lock); 74296fd7ce5SGreg Kroah-Hartman 74396fd7ce5SGreg Kroah-Hartman /* 74496fd7ce5SGreg Kroah-Hartman * If one of the devices matches a console pointer, we 74596fd7ce5SGreg Kroah-Hartman * cannot just call hangup() because that will cause 74696fd7ce5SGreg Kroah-Hartman * tty->count and state->count to go out of sync. 74796fd7ce5SGreg Kroah-Hartman * So we just call close() the right number of times. 74896fd7ce5SGreg Kroah-Hartman */ 74996fd7ce5SGreg Kroah-Hartman if (cons_filp) { 75096fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 75196fd7ce5SGreg Kroah-Hartman for (n = 0; n < closecount; n++) 75296fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, cons_filp); 75396fd7ce5SGreg Kroah-Hartman } else if (tty->ops->hangup) 7547c6d340fSPeter Hurley tty->ops->hangup(tty); 75596fd7ce5SGreg Kroah-Hartman /* 75696fd7ce5SGreg Kroah-Hartman * We don't want to have driver/ldisc interactions beyond 75796fd7ce5SGreg Kroah-Hartman * the ones we did here. The driver layer expects no 75896fd7ce5SGreg Kroah-Hartman * calls after ->hangup() from the ldisc side. However we 75996fd7ce5SGreg Kroah-Hartman * can't yet guarantee all that. 76096fd7ce5SGreg Kroah-Hartman */ 76196fd7ce5SGreg Kroah-Hartman set_bit(TTY_HUPPED, &tty->flags); 76289c8d91eSAlan Cox tty_unlock(tty); 76396fd7ce5SGreg Kroah-Hartman 76496fd7ce5SGreg Kroah-Hartman if (f) 76596fd7ce5SGreg Kroah-Hartman fput(f); 76696fd7ce5SGreg Kroah-Hartman } 76796fd7ce5SGreg Kroah-Hartman 76896fd7ce5SGreg Kroah-Hartman static void do_tty_hangup(struct work_struct *work) 76996fd7ce5SGreg Kroah-Hartman { 77096fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 77196fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 77296fd7ce5SGreg Kroah-Hartman 773f91e2590SPeter Hurley __tty_hangup(tty, 0); 77496fd7ce5SGreg Kroah-Hartman } 77596fd7ce5SGreg Kroah-Hartman 77696fd7ce5SGreg Kroah-Hartman /** 77796fd7ce5SGreg Kroah-Hartman * tty_hangup - trigger a hangup event 77896fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 77996fd7ce5SGreg Kroah-Hartman * 78096fd7ce5SGreg Kroah-Hartman * A carrier loss (virtual or otherwise) has occurred on this like 78196fd7ce5SGreg Kroah-Hartman * schedule a hangup sequence to run after this event. 78296fd7ce5SGreg Kroah-Hartman */ 78396fd7ce5SGreg Kroah-Hartman 78496fd7ce5SGreg Kroah-Hartman void tty_hangup(struct tty_struct *tty) 78596fd7ce5SGreg Kroah-Hartman { 786d435cefeSPeter Hurley tty_debug_hangup(tty, "hangup\n"); 78796fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 78896fd7ce5SGreg Kroah-Hartman } 78996fd7ce5SGreg Kroah-Hartman 79096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hangup); 79196fd7ce5SGreg Kroah-Hartman 79296fd7ce5SGreg Kroah-Hartman /** 79396fd7ce5SGreg Kroah-Hartman * tty_vhangup - process vhangup 79496fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 79596fd7ce5SGreg Kroah-Hartman * 79696fd7ce5SGreg Kroah-Hartman * The user has asked via system call for the terminal to be hung up. 79796fd7ce5SGreg Kroah-Hartman * We do this synchronously so that when the syscall returns the process 79896fd7ce5SGreg Kroah-Hartman * is complete. That guarantee is necessary for security reasons. 79996fd7ce5SGreg Kroah-Hartman */ 80096fd7ce5SGreg Kroah-Hartman 80196fd7ce5SGreg Kroah-Hartman void tty_vhangup(struct tty_struct *tty) 80296fd7ce5SGreg Kroah-Hartman { 803d435cefeSPeter Hurley tty_debug_hangup(tty, "vhangup\n"); 804f91e2590SPeter Hurley __tty_hangup(tty, 0); 80596fd7ce5SGreg Kroah-Hartman } 80696fd7ce5SGreg Kroah-Hartman 80796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_vhangup); 80896fd7ce5SGreg Kroah-Hartman 80996fd7ce5SGreg Kroah-Hartman 81096fd7ce5SGreg Kroah-Hartman /** 81196fd7ce5SGreg Kroah-Hartman * tty_vhangup_self - process vhangup for own ctty 81296fd7ce5SGreg Kroah-Hartman * 81396fd7ce5SGreg Kroah-Hartman * Perform a vhangup on the current controlling tty 81496fd7ce5SGreg Kroah-Hartman */ 81596fd7ce5SGreg Kroah-Hartman 81696fd7ce5SGreg Kroah-Hartman void tty_vhangup_self(void) 81796fd7ce5SGreg Kroah-Hartman { 81896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 81996fd7ce5SGreg Kroah-Hartman 82096fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 82196fd7ce5SGreg Kroah-Hartman if (tty) { 82296fd7ce5SGreg Kroah-Hartman tty_vhangup(tty); 82396fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 82496fd7ce5SGreg Kroah-Hartman } 82596fd7ce5SGreg Kroah-Hartman } 82696fd7ce5SGreg Kroah-Hartman 82796fd7ce5SGreg Kroah-Hartman /** 828f91e2590SPeter Hurley * tty_vhangup_session - hangup session leader exit 829f91e2590SPeter Hurley * @tty: tty to hangup 830f91e2590SPeter Hurley * 831f91e2590SPeter Hurley * The session leader is exiting and hanging up its controlling terminal. 832f91e2590SPeter Hurley * Every process in the foreground process group is signalled SIGHUP. 833f91e2590SPeter Hurley * 834f91e2590SPeter Hurley * We do this synchronously so that when the syscall returns the process 835f91e2590SPeter Hurley * is complete. That guarantee is necessary for security reasons. 836f91e2590SPeter Hurley */ 837f91e2590SPeter Hurley 83844a459fdSChanglong Xie static void tty_vhangup_session(struct tty_struct *tty) 839f91e2590SPeter Hurley { 840d435cefeSPeter Hurley tty_debug_hangup(tty, "session hangup\n"); 841f91e2590SPeter Hurley __tty_hangup(tty, 1); 842f91e2590SPeter Hurley } 843f91e2590SPeter Hurley 844f91e2590SPeter Hurley /** 84596fd7ce5SGreg Kroah-Hartman * tty_hung_up_p - was tty hung up 84696fd7ce5SGreg Kroah-Hartman * @filp: file pointer of tty 84796fd7ce5SGreg Kroah-Hartman * 84896fd7ce5SGreg Kroah-Hartman * Return true if the tty has been subject to a vhangup or a carrier 84996fd7ce5SGreg Kroah-Hartman * loss 85096fd7ce5SGreg Kroah-Hartman */ 85196fd7ce5SGreg Kroah-Hartman 85296fd7ce5SGreg Kroah-Hartman int tty_hung_up_p(struct file *filp) 85396fd7ce5SGreg Kroah-Hartman { 85496fd7ce5SGreg Kroah-Hartman return (filp->f_op == &hung_up_tty_fops); 85596fd7ce5SGreg Kroah-Hartman } 85696fd7ce5SGreg Kroah-Hartman 85796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hung_up_p); 85896fd7ce5SGreg Kroah-Hartman 85996fd7ce5SGreg Kroah-Hartman /** 86096fd7ce5SGreg Kroah-Hartman * disassociate_ctty - disconnect controlling tty 86196fd7ce5SGreg Kroah-Hartman * @on_exit: true if exiting so need to "hang up" the session 86296fd7ce5SGreg Kroah-Hartman * 86396fd7ce5SGreg Kroah-Hartman * This function is typically called only by the session leader, when 86496fd7ce5SGreg Kroah-Hartman * it wants to disassociate itself from its controlling tty. 86596fd7ce5SGreg Kroah-Hartman * 86696fd7ce5SGreg Kroah-Hartman * It performs the following functions: 86796fd7ce5SGreg Kroah-Hartman * (1) Sends a SIGHUP and SIGCONT to the foreground process group 86896fd7ce5SGreg Kroah-Hartman * (2) Clears the tty from being controlling the session 86996fd7ce5SGreg Kroah-Hartman * (3) Clears the controlling tty for all processes in the 87096fd7ce5SGreg Kroah-Hartman * session group. 87196fd7ce5SGreg Kroah-Hartman * 87296fd7ce5SGreg Kroah-Hartman * The argument on_exit is set to 1 if called when a process is 87396fd7ce5SGreg Kroah-Hartman * exiting; it is 0 if called by the ioctl TIOCNOTTY. 87496fd7ce5SGreg Kroah-Hartman * 87596fd7ce5SGreg Kroah-Hartman * Locking: 87696fd7ce5SGreg Kroah-Hartman * BTM is taken for hysterical raisins, and held when 87796fd7ce5SGreg Kroah-Hartman * called from no_tty(). 87896fd7ce5SGreg Kroah-Hartman * tty_mutex is taken to protect tty 87996fd7ce5SGreg Kroah-Hartman * ->siglock is taken to protect ->signal/->sighand 88096fd7ce5SGreg Kroah-Hartman * tasklist_lock is taken to walk process list for sessions 88196fd7ce5SGreg Kroah-Hartman * ->siglock is taken to protect ->signal/->sighand 88296fd7ce5SGreg Kroah-Hartman */ 88396fd7ce5SGreg Kroah-Hartman 88496fd7ce5SGreg Kroah-Hartman void disassociate_ctty(int on_exit) 88596fd7ce5SGreg Kroah-Hartman { 88696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 88796fd7ce5SGreg Kroah-Hartman 88896fd7ce5SGreg Kroah-Hartman if (!current->signal->leader) 88996fd7ce5SGreg Kroah-Hartman return; 89096fd7ce5SGreg Kroah-Hartman 89196fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 89296fd7ce5SGreg Kroah-Hartman if (tty) { 893f91e2590SPeter Hurley if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) { 894f91e2590SPeter Hurley tty_vhangup_session(tty); 895f91e2590SPeter Hurley } else { 896f91e2590SPeter Hurley struct pid *tty_pgrp = tty_get_pgrp(tty); 8971411dc4aSJiri Slaby if (tty_pgrp) { 8981411dc4aSJiri Slaby kill_pgrp(tty_pgrp, SIGHUP, on_exit); 89903e12617SOleg Nesterov if (!on_exit) 9001411dc4aSJiri Slaby kill_pgrp(tty_pgrp, SIGCONT, on_exit); 9011411dc4aSJiri Slaby put_pid(tty_pgrp); 9021411dc4aSJiri Slaby } 903f91e2590SPeter Hurley } 904f91e2590SPeter Hurley tty_kref_put(tty); 905f91e2590SPeter Hurley 90696fd7ce5SGreg Kroah-Hartman } else if (on_exit) { 90796fd7ce5SGreg Kroah-Hartman struct pid *old_pgrp; 90896fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 90996fd7ce5SGreg Kroah-Hartman old_pgrp = current->signal->tty_old_pgrp; 91096fd7ce5SGreg Kroah-Hartman current->signal->tty_old_pgrp = NULL; 91196fd7ce5SGreg Kroah-Hartman spin_unlock_irq(¤t->sighand->siglock); 91296fd7ce5SGreg Kroah-Hartman if (old_pgrp) { 91396fd7ce5SGreg Kroah-Hartman kill_pgrp(old_pgrp, SIGHUP, on_exit); 91496fd7ce5SGreg Kroah-Hartman kill_pgrp(old_pgrp, SIGCONT, on_exit); 91596fd7ce5SGreg Kroah-Hartman put_pid(old_pgrp); 91696fd7ce5SGreg Kroah-Hartman } 91796fd7ce5SGreg Kroah-Hartman return; 91896fd7ce5SGreg Kroah-Hartman } 91996fd7ce5SGreg Kroah-Hartman 92096fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 92196fd7ce5SGreg Kroah-Hartman put_pid(current->signal->tty_old_pgrp); 92296fd7ce5SGreg Kroah-Hartman current->signal->tty_old_pgrp = NULL; 92396fd7ce5SGreg Kroah-Hartman 924c70dbb1eSChen Tingjie tty = tty_kref_get(current->signal->tty); 92596fd7ce5SGreg Kroah-Hartman if (tty) { 92696fd7ce5SGreg Kroah-Hartman unsigned long flags; 92796fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 92896fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 92996fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 93096fd7ce5SGreg Kroah-Hartman tty->session = NULL; 93196fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 93296fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 93396fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 934accff793SPeter Hurley } else 935accff793SPeter Hurley tty_debug_hangup(tty, "no current tty\n"); 93696fd7ce5SGreg Kroah-Hartman 937c70dbb1eSChen Tingjie spin_unlock_irq(¤t->sighand->siglock); 93896fd7ce5SGreg Kroah-Hartman /* Now clear signal->tty under the lock */ 93996fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 94096fd7ce5SGreg Kroah-Hartman session_clear_tty(task_session(current)); 94196fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 94296fd7ce5SGreg Kroah-Hartman } 94396fd7ce5SGreg Kroah-Hartman 94496fd7ce5SGreg Kroah-Hartman /** 94596fd7ce5SGreg Kroah-Hartman * 94696fd7ce5SGreg Kroah-Hartman * no_tty - Ensure the current process does not have a controlling tty 94796fd7ce5SGreg Kroah-Hartman */ 94896fd7ce5SGreg Kroah-Hartman void no_tty(void) 94996fd7ce5SGreg Kroah-Hartman { 9503af502b9SAlan Cox /* FIXME: Review locking here. The tty_lock never covered any race 9513af502b9SAlan Cox between a new association and proc_clear_tty but possible we need 9523af502b9SAlan Cox to protect against this anyway */ 95396fd7ce5SGreg Kroah-Hartman struct task_struct *tsk = current; 95496fd7ce5SGreg Kroah-Hartman disassociate_ctty(0); 95596fd7ce5SGreg Kroah-Hartman proc_clear_tty(tsk); 95696fd7ce5SGreg Kroah-Hartman } 95796fd7ce5SGreg Kroah-Hartman 95896fd7ce5SGreg Kroah-Hartman 95996fd7ce5SGreg Kroah-Hartman /** 96096fd7ce5SGreg Kroah-Hartman * stop_tty - propagate flow control 96196fd7ce5SGreg Kroah-Hartman * @tty: tty to stop 96296fd7ce5SGreg Kroah-Hartman * 96301adc807SPeter Hurley * Perform flow control to the driver. May be called 96496fd7ce5SGreg Kroah-Hartman * on an already stopped device and will not re-call the driver 96596fd7ce5SGreg Kroah-Hartman * method. 96696fd7ce5SGreg Kroah-Hartman * 96796fd7ce5SGreg Kroah-Hartman * This functionality is used by both the line disciplines for 96896fd7ce5SGreg Kroah-Hartman * halting incoming flow and by the driver. It may therefore be 96996fd7ce5SGreg Kroah-Hartman * called from any context, may be under the tty atomic_write_lock 97096fd7ce5SGreg Kroah-Hartman * but not always. 97196fd7ce5SGreg Kroah-Hartman * 97296fd7ce5SGreg Kroah-Hartman * Locking: 973f9e053dcSPeter Hurley * flow_lock 97496fd7ce5SGreg Kroah-Hartman */ 97596fd7ce5SGreg Kroah-Hartman 976f9e053dcSPeter Hurley void __stop_tty(struct tty_struct *tty) 97796fd7ce5SGreg Kroah-Hartman { 978f9e053dcSPeter Hurley if (tty->stopped) 97996fd7ce5SGreg Kroah-Hartman return; 98096fd7ce5SGreg Kroah-Hartman tty->stopped = 1; 98196fd7ce5SGreg Kroah-Hartman if (tty->ops->stop) 982c961bfb1SPeter Hurley tty->ops->stop(tty); 98396fd7ce5SGreg Kroah-Hartman } 98496fd7ce5SGreg Kroah-Hartman 985f9e053dcSPeter Hurley void stop_tty(struct tty_struct *tty) 986f9e053dcSPeter Hurley { 987f9e053dcSPeter Hurley unsigned long flags; 988f9e053dcSPeter Hurley 989f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 990f9e053dcSPeter Hurley __stop_tty(tty); 991f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 992f9e053dcSPeter Hurley } 99396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(stop_tty); 99496fd7ce5SGreg Kroah-Hartman 99596fd7ce5SGreg Kroah-Hartman /** 99696fd7ce5SGreg Kroah-Hartman * start_tty - propagate flow control 99796fd7ce5SGreg Kroah-Hartman * @tty: tty to start 99896fd7ce5SGreg Kroah-Hartman * 99901adc807SPeter Hurley * Start a tty that has been stopped if at all possible. If this 100001adc807SPeter Hurley * tty was previous stopped and is now being started, the driver 100101adc807SPeter Hurley * start method is invoked and the line discipline woken. 100296fd7ce5SGreg Kroah-Hartman * 100396fd7ce5SGreg Kroah-Hartman * Locking: 1004f9e053dcSPeter Hurley * flow_lock 100596fd7ce5SGreg Kroah-Hartman */ 100696fd7ce5SGreg Kroah-Hartman 1007f9e053dcSPeter Hurley void __start_tty(struct tty_struct *tty) 100896fd7ce5SGreg Kroah-Hartman { 1009f9e053dcSPeter Hurley if (!tty->stopped || tty->flow_stopped) 101096fd7ce5SGreg Kroah-Hartman return; 101196fd7ce5SGreg Kroah-Hartman tty->stopped = 0; 101296fd7ce5SGreg Kroah-Hartman if (tty->ops->start) 1013c961bfb1SPeter Hurley tty->ops->start(tty); 101496fd7ce5SGreg Kroah-Hartman tty_wakeup(tty); 101596fd7ce5SGreg Kroah-Hartman } 101696fd7ce5SGreg Kroah-Hartman 1017f9e053dcSPeter Hurley void start_tty(struct tty_struct *tty) 1018f9e053dcSPeter Hurley { 1019f9e053dcSPeter Hurley unsigned long flags; 1020f9e053dcSPeter Hurley 1021f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 1022f9e053dcSPeter Hurley __start_tty(tty); 1023f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 1024f9e053dcSPeter Hurley } 102596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(start_tty); 102696fd7ce5SGreg Kroah-Hartman 102737b7f3c7SJiri Slaby static void tty_update_time(struct timespec *time) 102837b7f3c7SJiri Slaby { 1029f0bf0bd0SJiri Slaby unsigned long sec = get_seconds(); 1030fbf47635SGreg Kroah-Hartman 1031fbf47635SGreg Kroah-Hartman /* 1032fbf47635SGreg Kroah-Hartman * We only care if the two values differ in anything other than the 1033fbf47635SGreg Kroah-Hartman * lower three bits (i.e every 8 seconds). If so, then we can update 1034fbf47635SGreg Kroah-Hartman * the time of the tty device, otherwise it could be construded as a 1035fbf47635SGreg Kroah-Hartman * security leak to let userspace know the exact timing of the tty. 1036fbf47635SGreg Kroah-Hartman */ 1037fbf47635SGreg Kroah-Hartman if ((sec ^ time->tv_sec) & ~7) 103837b7f3c7SJiri Slaby time->tv_sec = sec; 103937b7f3c7SJiri Slaby } 104037b7f3c7SJiri Slaby 104196fd7ce5SGreg Kroah-Hartman /** 104296fd7ce5SGreg Kroah-Hartman * tty_read - read method for tty device files 104396fd7ce5SGreg Kroah-Hartman * @file: pointer to tty file 104496fd7ce5SGreg Kroah-Hartman * @buf: user buffer 104596fd7ce5SGreg Kroah-Hartman * @count: size of user buffer 104696fd7ce5SGreg Kroah-Hartman * @ppos: unused 104796fd7ce5SGreg Kroah-Hartman * 104896fd7ce5SGreg Kroah-Hartman * Perform the read system call function on this terminal device. Checks 104996fd7ce5SGreg Kroah-Hartman * for hung up devices before calling the line discipline method. 105096fd7ce5SGreg Kroah-Hartman * 105196fd7ce5SGreg Kroah-Hartman * Locking: 105296fd7ce5SGreg Kroah-Hartman * Locks the line discipline internally while needed. Multiple 105396fd7ce5SGreg Kroah-Hartman * read calls may be outstanding in parallel. 105496fd7ce5SGreg Kroah-Hartman */ 105596fd7ce5SGreg Kroah-Hartman 105696fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *file, char __user *buf, size_t count, 105796fd7ce5SGreg Kroah-Hartman loff_t *ppos) 105896fd7ce5SGreg Kroah-Hartman { 105996fd7ce5SGreg Kroah-Hartman int i; 106037b7f3c7SJiri Slaby struct inode *inode = file_inode(file); 106196fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 106296fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 106396fd7ce5SGreg Kroah-Hartman 106437b7f3c7SJiri Slaby if (tty_paranoia_check(tty, inode, "tty_read")) 106596fd7ce5SGreg Kroah-Hartman return -EIO; 106696fd7ce5SGreg Kroah-Hartman if (!tty || (test_bit(TTY_IO_ERROR, &tty->flags))) 106796fd7ce5SGreg Kroah-Hartman return -EIO; 106896fd7ce5SGreg Kroah-Hartman 106996fd7ce5SGreg Kroah-Hartman /* We want to wait for the line discipline to sort out in this 107096fd7ce5SGreg Kroah-Hartman situation */ 107196fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 107296fd7ce5SGreg Kroah-Hartman if (ld->ops->read) 1073c961bfb1SPeter Hurley i = ld->ops->read(tty, file, buf, count); 107496fd7ce5SGreg Kroah-Hartman else 107596fd7ce5SGreg Kroah-Hartman i = -EIO; 107696fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 1077b0de59b5SJiri Slaby 107837b7f3c7SJiri Slaby if (i > 0) 107937b7f3c7SJiri Slaby tty_update_time(&inode->i_atime); 108037b7f3c7SJiri Slaby 108196fd7ce5SGreg Kroah-Hartman return i; 108296fd7ce5SGreg Kroah-Hartman } 108396fd7ce5SGreg Kroah-Hartman 1084136d5258SPeter Hurley static void tty_write_unlock(struct tty_struct *tty) 108596fd7ce5SGreg Kroah-Hartman { 108696fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty->atomic_write_lock); 108796fd7ce5SGreg Kroah-Hartman wake_up_interruptible_poll(&tty->write_wait, POLLOUT); 108896fd7ce5SGreg Kroah-Hartman } 108996fd7ce5SGreg Kroah-Hartman 1090136d5258SPeter Hurley static int tty_write_lock(struct tty_struct *tty, int ndelay) 109196fd7ce5SGreg Kroah-Hartman { 109296fd7ce5SGreg Kroah-Hartman if (!mutex_trylock(&tty->atomic_write_lock)) { 109396fd7ce5SGreg Kroah-Hartman if (ndelay) 109496fd7ce5SGreg Kroah-Hartman return -EAGAIN; 109596fd7ce5SGreg Kroah-Hartman if (mutex_lock_interruptible(&tty->atomic_write_lock)) 109696fd7ce5SGreg Kroah-Hartman return -ERESTARTSYS; 109796fd7ce5SGreg Kroah-Hartman } 109896fd7ce5SGreg Kroah-Hartman return 0; 109996fd7ce5SGreg Kroah-Hartman } 110096fd7ce5SGreg Kroah-Hartman 110196fd7ce5SGreg Kroah-Hartman /* 110296fd7ce5SGreg Kroah-Hartman * Split writes up in sane blocksizes to avoid 110396fd7ce5SGreg Kroah-Hartman * denial-of-service type attacks 110496fd7ce5SGreg Kroah-Hartman */ 110596fd7ce5SGreg Kroah-Hartman static inline ssize_t do_tty_write( 110696fd7ce5SGreg Kroah-Hartman ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), 110796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty, 110896fd7ce5SGreg Kroah-Hartman struct file *file, 110996fd7ce5SGreg Kroah-Hartman const char __user *buf, 111096fd7ce5SGreg Kroah-Hartman size_t count) 111196fd7ce5SGreg Kroah-Hartman { 111296fd7ce5SGreg Kroah-Hartman ssize_t ret, written = 0; 111396fd7ce5SGreg Kroah-Hartman unsigned int chunk; 111496fd7ce5SGreg Kroah-Hartman 111596fd7ce5SGreg Kroah-Hartman ret = tty_write_lock(tty, file->f_flags & O_NDELAY); 111696fd7ce5SGreg Kroah-Hartman if (ret < 0) 111796fd7ce5SGreg Kroah-Hartman return ret; 111896fd7ce5SGreg Kroah-Hartman 111996fd7ce5SGreg Kroah-Hartman /* 112096fd7ce5SGreg Kroah-Hartman * We chunk up writes into a temporary buffer. This 112196fd7ce5SGreg Kroah-Hartman * simplifies low-level drivers immensely, since they 112296fd7ce5SGreg Kroah-Hartman * don't have locking issues and user mode accesses. 112396fd7ce5SGreg Kroah-Hartman * 112496fd7ce5SGreg Kroah-Hartman * But if TTY_NO_WRITE_SPLIT is set, we should use a 112596fd7ce5SGreg Kroah-Hartman * big chunk-size.. 112696fd7ce5SGreg Kroah-Hartman * 112796fd7ce5SGreg Kroah-Hartman * The default chunk-size is 2kB, because the NTTY 112896fd7ce5SGreg Kroah-Hartman * layer has problems with bigger chunks. It will 112996fd7ce5SGreg Kroah-Hartman * claim to be able to handle more characters than 113096fd7ce5SGreg Kroah-Hartman * it actually does. 113196fd7ce5SGreg Kroah-Hartman * 113296fd7ce5SGreg Kroah-Hartman * FIXME: This can probably go away now except that 64K chunks 113396fd7ce5SGreg Kroah-Hartman * are too likely to fail unless switched to vmalloc... 113496fd7ce5SGreg Kroah-Hartman */ 113596fd7ce5SGreg Kroah-Hartman chunk = 2048; 113696fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) 113796fd7ce5SGreg Kroah-Hartman chunk = 65536; 113896fd7ce5SGreg Kroah-Hartman if (count < chunk) 113996fd7ce5SGreg Kroah-Hartman chunk = count; 114096fd7ce5SGreg Kroah-Hartman 114196fd7ce5SGreg Kroah-Hartman /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ 114296fd7ce5SGreg Kroah-Hartman if (tty->write_cnt < chunk) { 114396fd7ce5SGreg Kroah-Hartman unsigned char *buf_chunk; 114496fd7ce5SGreg Kroah-Hartman 114596fd7ce5SGreg Kroah-Hartman if (chunk < 1024) 114696fd7ce5SGreg Kroah-Hartman chunk = 1024; 114796fd7ce5SGreg Kroah-Hartman 114896fd7ce5SGreg Kroah-Hartman buf_chunk = kmalloc(chunk, GFP_KERNEL); 114996fd7ce5SGreg Kroah-Hartman if (!buf_chunk) { 115096fd7ce5SGreg Kroah-Hartman ret = -ENOMEM; 115196fd7ce5SGreg Kroah-Hartman goto out; 115296fd7ce5SGreg Kroah-Hartman } 115396fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 115496fd7ce5SGreg Kroah-Hartman tty->write_cnt = chunk; 115596fd7ce5SGreg Kroah-Hartman tty->write_buf = buf_chunk; 115696fd7ce5SGreg Kroah-Hartman } 115796fd7ce5SGreg Kroah-Hartman 115896fd7ce5SGreg Kroah-Hartman /* Do the write .. */ 115996fd7ce5SGreg Kroah-Hartman for (;;) { 116096fd7ce5SGreg Kroah-Hartman size_t size = count; 116196fd7ce5SGreg Kroah-Hartman if (size > chunk) 116296fd7ce5SGreg Kroah-Hartman size = chunk; 116396fd7ce5SGreg Kroah-Hartman ret = -EFAULT; 116496fd7ce5SGreg Kroah-Hartman if (copy_from_user(tty->write_buf, buf, size)) 116596fd7ce5SGreg Kroah-Hartman break; 116696fd7ce5SGreg Kroah-Hartman ret = write(tty, file, tty->write_buf, size); 116796fd7ce5SGreg Kroah-Hartman if (ret <= 0) 116896fd7ce5SGreg Kroah-Hartman break; 116996fd7ce5SGreg Kroah-Hartman written += ret; 117096fd7ce5SGreg Kroah-Hartman buf += ret; 117196fd7ce5SGreg Kroah-Hartman count -= ret; 117296fd7ce5SGreg Kroah-Hartman if (!count) 117396fd7ce5SGreg Kroah-Hartman break; 117496fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 117596fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 117696fd7ce5SGreg Kroah-Hartman break; 117796fd7ce5SGreg Kroah-Hartman cond_resched(); 117896fd7ce5SGreg Kroah-Hartman } 117937b7f3c7SJiri Slaby if (written) { 118037b7f3c7SJiri Slaby tty_update_time(&file_inode(file)->i_mtime); 118196fd7ce5SGreg Kroah-Hartman ret = written; 118237b7f3c7SJiri Slaby } 118396fd7ce5SGreg Kroah-Hartman out: 118496fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 118596fd7ce5SGreg Kroah-Hartman return ret; 118696fd7ce5SGreg Kroah-Hartman } 118796fd7ce5SGreg Kroah-Hartman 118896fd7ce5SGreg Kroah-Hartman /** 118996fd7ce5SGreg Kroah-Hartman * tty_write_message - write a message to a certain tty, not just the console. 119096fd7ce5SGreg Kroah-Hartman * @tty: the destination tty_struct 119196fd7ce5SGreg Kroah-Hartman * @msg: the message to write 119296fd7ce5SGreg Kroah-Hartman * 119396fd7ce5SGreg Kroah-Hartman * This is used for messages that need to be redirected to a specific tty. 119496fd7ce5SGreg Kroah-Hartman * We don't put it into the syslog queue right now maybe in the future if 119596fd7ce5SGreg Kroah-Hartman * really needed. 119696fd7ce5SGreg Kroah-Hartman * 119796fd7ce5SGreg Kroah-Hartman * We must still hold the BTM and test the CLOSING flag for the moment. 119896fd7ce5SGreg Kroah-Hartman */ 119996fd7ce5SGreg Kroah-Hartman 120096fd7ce5SGreg Kroah-Hartman void tty_write_message(struct tty_struct *tty, char *msg) 120196fd7ce5SGreg Kroah-Hartman { 120296fd7ce5SGreg Kroah-Hartman if (tty) { 120396fd7ce5SGreg Kroah-Hartman mutex_lock(&tty->atomic_write_lock); 120489c8d91eSAlan Cox tty_lock(tty); 12054b41b953SPeter Hurley if (tty->ops->write && tty->count > 0) 120696fd7ce5SGreg Kroah-Hartman tty->ops->write(tty, msg, strlen(msg)); 120789c8d91eSAlan Cox tty_unlock(tty); 120896fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 120996fd7ce5SGreg Kroah-Hartman } 121096fd7ce5SGreg Kroah-Hartman return; 121196fd7ce5SGreg Kroah-Hartman } 121296fd7ce5SGreg Kroah-Hartman 121396fd7ce5SGreg Kroah-Hartman 121496fd7ce5SGreg Kroah-Hartman /** 121596fd7ce5SGreg Kroah-Hartman * tty_write - write method for tty device file 121696fd7ce5SGreg Kroah-Hartman * @file: tty file pointer 121796fd7ce5SGreg Kroah-Hartman * @buf: user data to write 121896fd7ce5SGreg Kroah-Hartman * @count: bytes to write 121996fd7ce5SGreg Kroah-Hartman * @ppos: unused 122096fd7ce5SGreg Kroah-Hartman * 122196fd7ce5SGreg Kroah-Hartman * Write data to a tty device via the line discipline. 122296fd7ce5SGreg Kroah-Hartman * 122396fd7ce5SGreg Kroah-Hartman * Locking: 122496fd7ce5SGreg Kroah-Hartman * Locks the line discipline as required 122596fd7ce5SGreg Kroah-Hartman * Writes to the tty driver are serialized by the atomic_write_lock 122696fd7ce5SGreg Kroah-Hartman * and are then processed in chunks to the device. The line discipline 122796fd7ce5SGreg Kroah-Hartman * write method will not be invoked in parallel for each device. 122896fd7ce5SGreg Kroah-Hartman */ 122996fd7ce5SGreg Kroah-Hartman 123096fd7ce5SGreg Kroah-Hartman static ssize_t tty_write(struct file *file, const char __user *buf, 123196fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 123296fd7ce5SGreg Kroah-Hartman { 123396fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 123496fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 123596fd7ce5SGreg Kroah-Hartman ssize_t ret; 123696fd7ce5SGreg Kroah-Hartman 12376131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_write")) 123896fd7ce5SGreg Kroah-Hartman return -EIO; 123996fd7ce5SGreg Kroah-Hartman if (!tty || !tty->ops->write || 124096fd7ce5SGreg Kroah-Hartman (test_bit(TTY_IO_ERROR, &tty->flags))) 124196fd7ce5SGreg Kroah-Hartman return -EIO; 124296fd7ce5SGreg Kroah-Hartman /* Short term debug to catch buggy drivers */ 124396fd7ce5SGreg Kroah-Hartman if (tty->ops->write_room == NULL) 1244339f36baSPeter Hurley tty_err(tty, "missing write_room method\n"); 124596fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 124696fd7ce5SGreg Kroah-Hartman if (!ld->ops->write) 124796fd7ce5SGreg Kroah-Hartman ret = -EIO; 124896fd7ce5SGreg Kroah-Hartman else 124996fd7ce5SGreg Kroah-Hartman ret = do_tty_write(ld->ops->write, tty, file, buf, count); 125096fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 125196fd7ce5SGreg Kroah-Hartman return ret; 125296fd7ce5SGreg Kroah-Hartman } 125396fd7ce5SGreg Kroah-Hartman 125496fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *file, const char __user *buf, 125596fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 125696fd7ce5SGreg Kroah-Hartman { 125796fd7ce5SGreg Kroah-Hartman struct file *p = NULL; 125896fd7ce5SGreg Kroah-Hartman 125996fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 1260cb0942b8SAl Viro if (redirect) 1261cb0942b8SAl Viro p = get_file(redirect); 126296fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 126396fd7ce5SGreg Kroah-Hartman 126496fd7ce5SGreg Kroah-Hartman if (p) { 126596fd7ce5SGreg Kroah-Hartman ssize_t res; 126696fd7ce5SGreg Kroah-Hartman res = vfs_write(p, buf, count, &p->f_pos); 126796fd7ce5SGreg Kroah-Hartman fput(p); 126896fd7ce5SGreg Kroah-Hartman return res; 126996fd7ce5SGreg Kroah-Hartman } 127096fd7ce5SGreg Kroah-Hartman return tty_write(file, buf, count, ppos); 127196fd7ce5SGreg Kroah-Hartman } 127296fd7ce5SGreg Kroah-Hartman 1273136d5258SPeter Hurley /** 1274136d5258SPeter Hurley * tty_send_xchar - send priority character 1275136d5258SPeter Hurley * 1276136d5258SPeter Hurley * Send a high priority character to the tty even if stopped 1277136d5258SPeter Hurley * 1278136d5258SPeter Hurley * Locking: none for xchar method, write ordering for write method. 1279136d5258SPeter Hurley */ 1280136d5258SPeter Hurley 1281136d5258SPeter Hurley int tty_send_xchar(struct tty_struct *tty, char ch) 1282136d5258SPeter Hurley { 1283136d5258SPeter Hurley int was_stopped = tty->stopped; 1284136d5258SPeter Hurley 1285136d5258SPeter Hurley if (tty->ops->send_xchar) { 1286ee0c1a65SPeter Hurley down_read(&tty->termios_rwsem); 1287136d5258SPeter Hurley tty->ops->send_xchar(tty, ch); 1288ee0c1a65SPeter Hurley up_read(&tty->termios_rwsem); 1289136d5258SPeter Hurley return 0; 1290136d5258SPeter Hurley } 1291136d5258SPeter Hurley 1292136d5258SPeter Hurley if (tty_write_lock(tty, 0) < 0) 1293136d5258SPeter Hurley return -ERESTARTSYS; 1294136d5258SPeter Hurley 1295ee0c1a65SPeter Hurley down_read(&tty->termios_rwsem); 1296136d5258SPeter Hurley if (was_stopped) 1297136d5258SPeter Hurley start_tty(tty); 1298136d5258SPeter Hurley tty->ops->write(tty, &ch, 1); 1299136d5258SPeter Hurley if (was_stopped) 1300136d5258SPeter Hurley stop_tty(tty); 1301ee0c1a65SPeter Hurley up_read(&tty->termios_rwsem); 1302136d5258SPeter Hurley tty_write_unlock(tty); 1303136d5258SPeter Hurley return 0; 1304136d5258SPeter Hurley } 1305136d5258SPeter Hurley 130696fd7ce5SGreg Kroah-Hartman static char ptychar[] = "pqrstuvwxyzabcde"; 130796fd7ce5SGreg Kroah-Hartman 130896fd7ce5SGreg Kroah-Hartman /** 130996fd7ce5SGreg Kroah-Hartman * pty_line_name - generate name for a pty 131096fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 131196fd7ce5SGreg Kroah-Hartman * @index: the minor number 131296fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 6 bytes 131396fd7ce5SGreg Kroah-Hartman * 131496fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 131596fd7ce5SGreg Kroah-Hartman * buffer. 131696fd7ce5SGreg Kroah-Hartman * 131796fd7ce5SGreg Kroah-Hartman * Locking: None 131896fd7ce5SGreg Kroah-Hartman */ 131996fd7ce5SGreg Kroah-Hartman static void pty_line_name(struct tty_driver *driver, int index, char *p) 132096fd7ce5SGreg Kroah-Hartman { 132196fd7ce5SGreg Kroah-Hartman int i = index + driver->name_base; 132296fd7ce5SGreg Kroah-Hartman /* ->name is initialized to "ttyp", but "tty" is expected */ 132396fd7ce5SGreg Kroah-Hartman sprintf(p, "%s%c%x", 132496fd7ce5SGreg Kroah-Hartman driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, 132596fd7ce5SGreg Kroah-Hartman ptychar[i >> 4 & 0xf], i & 0xf); 132696fd7ce5SGreg Kroah-Hartman } 132796fd7ce5SGreg Kroah-Hartman 132896fd7ce5SGreg Kroah-Hartman /** 132996fd7ce5SGreg Kroah-Hartman * tty_line_name - generate name for a tty 133096fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 133196fd7ce5SGreg Kroah-Hartman * @index: the minor number 133296fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 7 bytes 133396fd7ce5SGreg Kroah-Hartman * 133496fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 13355c0a2450SGreg Kroah-Hartman * buffer. 133696fd7ce5SGreg Kroah-Hartman * 133796fd7ce5SGreg Kroah-Hartman * Locking: None 133896fd7ce5SGreg Kroah-Hartman */ 1339723abd87SHannes Reinecke static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p) 134096fd7ce5SGreg Kroah-Hartman { 13410019b408SJiri Slaby if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE) 1342723abd87SHannes Reinecke return sprintf(p, "%s", driver->name); 13430019b408SJiri Slaby else 1344723abd87SHannes Reinecke return sprintf(p, "%s%d", driver->name, 1345723abd87SHannes Reinecke index + driver->name_base); 134696fd7ce5SGreg Kroah-Hartman } 134796fd7ce5SGreg Kroah-Hartman 134896fd7ce5SGreg Kroah-Hartman /** 134996fd7ce5SGreg Kroah-Hartman * tty_driver_lookup_tty() - find an existing tty, if any 135096fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 135196fd7ce5SGreg Kroah-Hartman * @idx: the minor number 135296fd7ce5SGreg Kroah-Hartman * 1353aa3cb814SPeter Hurley * Return the tty, if found. If not found, return NULL or ERR_PTR() if the 1354aa3cb814SPeter Hurley * driver lookup() method returns an error. 135596fd7ce5SGreg Kroah-Hartman * 1356aa3cb814SPeter Hurley * Locking: tty_mutex must be held. If the tty is found, bump the tty kref. 135796fd7ce5SGreg Kroah-Hartman */ 135896fd7ce5SGreg Kroah-Hartman static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, 135996fd7ce5SGreg Kroah-Hartman struct inode *inode, int idx) 136096fd7ce5SGreg Kroah-Hartman { 1361aa3cb814SPeter Hurley struct tty_struct *tty; 136296fd7ce5SGreg Kroah-Hartman 1363aa3cb814SPeter Hurley if (driver->ops->lookup) 1364aa3cb814SPeter Hurley tty = driver->ops->lookup(driver, inode, idx); 1365aa3cb814SPeter Hurley else 1366aa3cb814SPeter Hurley tty = driver->ttys[idx]; 1367aa3cb814SPeter Hurley 1368aa3cb814SPeter Hurley if (!IS_ERR(tty)) 1369aa3cb814SPeter Hurley tty_kref_get(tty); 1370aa3cb814SPeter Hurley return tty; 137196fd7ce5SGreg Kroah-Hartman } 137296fd7ce5SGreg Kroah-Hartman 137396fd7ce5SGreg Kroah-Hartman /** 137496fd7ce5SGreg Kroah-Hartman * tty_init_termios - helper for termios setup 137596fd7ce5SGreg Kroah-Hartman * @tty: the tty to set up 137696fd7ce5SGreg Kroah-Hartman * 137796fd7ce5SGreg Kroah-Hartman * Initialise the termios structures for this tty. Thus runs under 137896fd7ce5SGreg Kroah-Hartman * the tty_mutex currently so we can be relaxed about ordering. 137996fd7ce5SGreg Kroah-Hartman */ 138096fd7ce5SGreg Kroah-Hartman 138196fd7ce5SGreg Kroah-Hartman int tty_init_termios(struct tty_struct *tty) 138296fd7ce5SGreg Kroah-Hartman { 138396fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 138496fd7ce5SGreg Kroah-Hartman int idx = tty->index; 138596fd7ce5SGreg Kroah-Hartman 138636b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 138736b3c070SAlan Cox tty->termios = tty->driver->init_termios; 138836b3c070SAlan Cox else { 138936b3c070SAlan Cox /* Check for lazy saved data */ 139096fd7ce5SGreg Kroah-Hartman tp = tty->driver->termios[idx]; 139136b3c070SAlan Cox if (tp != NULL) 1392adc8d746SAlan Cox tty->termios = *tp; 139336b3c070SAlan Cox else 139436b3c070SAlan Cox tty->termios = tty->driver->init_termios; 139536b3c070SAlan Cox } 139696fd7ce5SGreg Kroah-Hartman /* Compatibility until drivers always set this */ 1397adc8d746SAlan Cox tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios); 1398adc8d746SAlan Cox tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios); 139996fd7ce5SGreg Kroah-Hartman return 0; 140096fd7ce5SGreg Kroah-Hartman } 140196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_init_termios); 140296fd7ce5SGreg Kroah-Hartman 140366d450e8SJiri Slaby int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty) 140466d450e8SJiri Slaby { 140566d450e8SJiri Slaby int ret = tty_init_termios(tty); 140666d450e8SJiri Slaby if (ret) 140766d450e8SJiri Slaby return ret; 140866d450e8SJiri Slaby 140966d450e8SJiri Slaby tty_driver_kref_get(driver); 141066d450e8SJiri Slaby tty->count++; 141166d450e8SJiri Slaby driver->ttys[tty->index] = tty; 141266d450e8SJiri Slaby return 0; 141366d450e8SJiri Slaby } 141466d450e8SJiri Slaby EXPORT_SYMBOL_GPL(tty_standard_install); 141566d450e8SJiri Slaby 141696fd7ce5SGreg Kroah-Hartman /** 141796fd7ce5SGreg Kroah-Hartman * tty_driver_install_tty() - install a tty entry in the driver 141896fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 141996fd7ce5SGreg Kroah-Hartman * @tty: the tty 142096fd7ce5SGreg Kroah-Hartman * 142196fd7ce5SGreg Kroah-Hartman * Install a tty object into the driver tables. The tty->index field 142296fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. This method is responsible 142396fd7ce5SGreg Kroah-Hartman * for ensuring any need additional structures are allocated and 142496fd7ce5SGreg Kroah-Hartman * configured. 142596fd7ce5SGreg Kroah-Hartman * 142696fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 142796fd7ce5SGreg Kroah-Hartman */ 142896fd7ce5SGreg Kroah-Hartman static int tty_driver_install_tty(struct tty_driver *driver, 142996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty) 143096fd7ce5SGreg Kroah-Hartman { 143166d450e8SJiri Slaby return driver->ops->install ? driver->ops->install(driver, tty) : 143266d450e8SJiri Slaby tty_standard_install(driver, tty); 143396fd7ce5SGreg Kroah-Hartman } 143496fd7ce5SGreg Kroah-Hartman 143596fd7ce5SGreg Kroah-Hartman /** 143696fd7ce5SGreg Kroah-Hartman * tty_driver_remove_tty() - remove a tty from the driver tables 143796fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 143896fd7ce5SGreg Kroah-Hartman * @idx: the minor number 143996fd7ce5SGreg Kroah-Hartman * 144096fd7ce5SGreg Kroah-Hartman * Remvoe a tty object from the driver tables. The tty->index field 144196fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. 144296fd7ce5SGreg Kroah-Hartman * 144396fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 144496fd7ce5SGreg Kroah-Hartman */ 144524d406a6SJiri Slaby void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty) 144696fd7ce5SGreg Kroah-Hartman { 144796fd7ce5SGreg Kroah-Hartman if (driver->ops->remove) 144896fd7ce5SGreg Kroah-Hartman driver->ops->remove(driver, tty); 144996fd7ce5SGreg Kroah-Hartman else 145096fd7ce5SGreg Kroah-Hartman driver->ttys[tty->index] = NULL; 145196fd7ce5SGreg Kroah-Hartman } 145296fd7ce5SGreg Kroah-Hartman 145396fd7ce5SGreg Kroah-Hartman /* 145496fd7ce5SGreg Kroah-Hartman * tty_reopen() - fast re-open of an open tty 145596fd7ce5SGreg Kroah-Hartman * @tty - the tty to open 145696fd7ce5SGreg Kroah-Hartman * 145796fd7ce5SGreg Kroah-Hartman * Return 0 on success, -errno on error. 14585d93e748SPeter Hurley * Re-opens on master ptys are not allowed and return -EIO. 145996fd7ce5SGreg Kroah-Hartman * 14605d93e748SPeter Hurley * Locking: Caller must hold tty_lock 146196fd7ce5SGreg Kroah-Hartman */ 146296fd7ce5SGreg Kroah-Hartman static int tty_reopen(struct tty_struct *tty) 146396fd7ce5SGreg Kroah-Hartman { 146496fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 146596fd7ce5SGreg Kroah-Hartman 1466216030ecSPeter Hurley if (!tty->count) 146796fd7ce5SGreg Kroah-Hartman return -EIO; 146896fd7ce5SGreg Kroah-Hartman 146996fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY && 14705d93e748SPeter Hurley driver->subtype == PTY_TYPE_MASTER) 147196fd7ce5SGreg Kroah-Hartman return -EIO; 147296fd7ce5SGreg Kroah-Hartman 147386f2c00fSPeter Hurley if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN)) 147486f2c00fSPeter Hurley return -EBUSY; 147586f2c00fSPeter Hurley 147696fd7ce5SGreg Kroah-Hartman tty->count++; 147796fd7ce5SGreg Kroah-Hartman 147836697529SPeter Hurley WARN_ON(!tty->ldisc); 147996fd7ce5SGreg Kroah-Hartman 148096fd7ce5SGreg Kroah-Hartman return 0; 148196fd7ce5SGreg Kroah-Hartman } 148296fd7ce5SGreg Kroah-Hartman 148396fd7ce5SGreg Kroah-Hartman /** 148496fd7ce5SGreg Kroah-Hartman * tty_init_dev - initialise a tty device 148596fd7ce5SGreg Kroah-Hartman * @driver: tty driver we are opening a device on 148696fd7ce5SGreg Kroah-Hartman * @idx: device index 148796fd7ce5SGreg Kroah-Hartman * @ret_tty: returned tty structure 148896fd7ce5SGreg Kroah-Hartman * 148996fd7ce5SGreg Kroah-Hartman * Prepare a tty device. This may not be a "new" clean device but 149096fd7ce5SGreg Kroah-Hartman * could also be an active device. The pty drivers require special 149196fd7ce5SGreg Kroah-Hartman * handling because of this. 149296fd7ce5SGreg Kroah-Hartman * 149396fd7ce5SGreg Kroah-Hartman * Locking: 149496fd7ce5SGreg Kroah-Hartman * The function is called under the tty_mutex, which 149596fd7ce5SGreg Kroah-Hartman * protects us from the tty struct or driver itself going away. 149696fd7ce5SGreg Kroah-Hartman * 149796fd7ce5SGreg Kroah-Hartman * On exit the tty device has the line discipline attached and 149896fd7ce5SGreg Kroah-Hartman * a reference count of 1. If a pair was created for pty/tty use 149996fd7ce5SGreg Kroah-Hartman * and the other was a pty master then it too has a reference count of 1. 150096fd7ce5SGreg Kroah-Hartman * 150196fd7ce5SGreg Kroah-Hartman * WSH 06/09/97: Rewritten to remove races and properly clean up after a 150296fd7ce5SGreg Kroah-Hartman * failed open. The new code protects the open with a mutex, so it's 150396fd7ce5SGreg Kroah-Hartman * really quite straightforward. The mutex locking can probably be 150496fd7ce5SGreg Kroah-Hartman * relaxed for the (most common) case of reopening a tty. 150596fd7ce5SGreg Kroah-Hartman */ 150696fd7ce5SGreg Kroah-Hartman 1507593a27c4SKonstantin Khlebnikov struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) 150896fd7ce5SGreg Kroah-Hartman { 150996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 151096fd7ce5SGreg Kroah-Hartman int retval; 151196fd7ce5SGreg Kroah-Hartman 151296fd7ce5SGreg Kroah-Hartman /* 151396fd7ce5SGreg Kroah-Hartman * First time open is complex, especially for PTY devices. 151496fd7ce5SGreg Kroah-Hartman * This code guarantees that either everything succeeds and the 151596fd7ce5SGreg Kroah-Hartman * TTY is ready for operation, or else the table slots are vacated 151696fd7ce5SGreg Kroah-Hartman * and the allocated memory released. (Except that the termios 151796fd7ce5SGreg Kroah-Hartman * and locked termios may be retained.) 151896fd7ce5SGreg Kroah-Hartman */ 151996fd7ce5SGreg Kroah-Hartman 152096fd7ce5SGreg Kroah-Hartman if (!try_module_get(driver->owner)) 152196fd7ce5SGreg Kroah-Hartman return ERR_PTR(-ENODEV); 152296fd7ce5SGreg Kroah-Hartman 15232c964a2fSRasmus Villemoes tty = alloc_tty_struct(driver, idx); 1524d5543503SJiri Slaby if (!tty) { 1525d5543503SJiri Slaby retval = -ENOMEM; 1526d5543503SJiri Slaby goto err_module_put; 1527d5543503SJiri Slaby } 152896fd7ce5SGreg Kroah-Hartman 152989c8d91eSAlan Cox tty_lock(tty); 153096fd7ce5SGreg Kroah-Hartman retval = tty_driver_install_tty(driver, tty); 1531d5543503SJiri Slaby if (retval < 0) 1532a9dccddbSJiri Slaby goto err_deinit_tty; 153396fd7ce5SGreg Kroah-Hartman 153404831dc1SJiri Slaby if (!tty->port) 153504831dc1SJiri Slaby tty->port = driver->ports[idx]; 153604831dc1SJiri Slaby 15375d4121c0SJiri Slaby WARN_RATELIMIT(!tty->port, 15385d4121c0SJiri Slaby "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", 15395d4121c0SJiri Slaby __func__, tty->driver->name); 15405d4121c0SJiri Slaby 1541967fab69SJiri Slaby tty->port->itty = tty; 1542967fab69SJiri Slaby 154396fd7ce5SGreg Kroah-Hartman /* 154496fd7ce5SGreg Kroah-Hartman * Structures all installed ... call the ldisc open routines. 154596fd7ce5SGreg Kroah-Hartman * If we fail here just call release_tty to clean up. No need 154696fd7ce5SGreg Kroah-Hartman * to decrement the use counts, as release_tty doesn't care. 154796fd7ce5SGreg Kroah-Hartman */ 154896fd7ce5SGreg Kroah-Hartman retval = tty_ldisc_setup(tty, tty->link); 154996fd7ce5SGreg Kroah-Hartman if (retval) 1550d5543503SJiri Slaby goto err_release_tty; 155189c8d91eSAlan Cox /* Return the tty locked so that it cannot vanish under the caller */ 155296fd7ce5SGreg Kroah-Hartman return tty; 155396fd7ce5SGreg Kroah-Hartman 1554a9dccddbSJiri Slaby err_deinit_tty: 155589c8d91eSAlan Cox tty_unlock(tty); 1556a9dccddbSJiri Slaby deinitialize_tty_struct(tty); 1557d5543503SJiri Slaby free_tty_struct(tty); 1558d5543503SJiri Slaby err_module_put: 155996fd7ce5SGreg Kroah-Hartman module_put(driver->owner); 1560d5543503SJiri Slaby return ERR_PTR(retval); 156196fd7ce5SGreg Kroah-Hartman 156296fd7ce5SGreg Kroah-Hartman /* call the tty release_tty routine to clean out this slot */ 1563d5543503SJiri Slaby err_release_tty: 156489c8d91eSAlan Cox tty_unlock(tty); 1565339f36baSPeter Hurley tty_info_ratelimited(tty, "ldisc open failed (%d), clearing slot %d\n", 1566339f36baSPeter Hurley retval, idx); 156796fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 156896fd7ce5SGreg Kroah-Hartman return ERR_PTR(retval); 156996fd7ce5SGreg Kroah-Hartman } 157096fd7ce5SGreg Kroah-Hartman 157196fd7ce5SGreg Kroah-Hartman void tty_free_termios(struct tty_struct *tty) 157296fd7ce5SGreg Kroah-Hartman { 157396fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 157496fd7ce5SGreg Kroah-Hartman int idx = tty->index; 157536b3c070SAlan Cox 157636b3c070SAlan Cox /* If the port is going to reset then it has no termios to save */ 157736b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 157836b3c070SAlan Cox return; 157936b3c070SAlan Cox 158036b3c070SAlan Cox /* Stash the termios data */ 1581adc8d746SAlan Cox tp = tty->driver->termios[idx]; 158236b3c070SAlan Cox if (tp == NULL) { 158336b3c070SAlan Cox tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL); 158425080652SPeter Hurley if (tp == NULL) 158536b3c070SAlan Cox return; 15864ac5d705SDan Carpenter tty->driver->termios[idx] = tp; 158736b3c070SAlan Cox } 158836b3c070SAlan Cox *tp = tty->termios; 158996fd7ce5SGreg Kroah-Hartman } 159096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_free_termios); 159196fd7ce5SGreg Kroah-Hartman 1592a2965b7bSPeter Hurley /** 1593949aa64fSPeter Hurley * tty_flush_works - flush all works of a tty/pty pair 1594949aa64fSPeter Hurley * @tty: tty device to flush works for (or either end of a pty pair) 1595a2965b7bSPeter Hurley * 1596949aa64fSPeter Hurley * Sync flush all works belonging to @tty (and the 'other' tty). 1597a2965b7bSPeter Hurley */ 1598a2965b7bSPeter Hurley static void tty_flush_works(struct tty_struct *tty) 1599a2965b7bSPeter Hurley { 1600a2965b7bSPeter Hurley flush_work(&tty->SAK_work); 1601a2965b7bSPeter Hurley flush_work(&tty->hangup_work); 1602949aa64fSPeter Hurley if (tty->link) { 1603949aa64fSPeter Hurley flush_work(&tty->link->SAK_work); 1604949aa64fSPeter Hurley flush_work(&tty->link->hangup_work); 1605949aa64fSPeter Hurley } 1606a2965b7bSPeter Hurley } 160796fd7ce5SGreg Kroah-Hartman 160896fd7ce5SGreg Kroah-Hartman /** 160996fd7ce5SGreg Kroah-Hartman * release_one_tty - release tty structure memory 161096fd7ce5SGreg Kroah-Hartman * @kref: kref of tty we are obliterating 161196fd7ce5SGreg Kroah-Hartman * 161296fd7ce5SGreg Kroah-Hartman * Releases memory associated with a tty structure, and clears out the 161396fd7ce5SGreg Kroah-Hartman * driver table slots. This function is called when a device is no longer 161496fd7ce5SGreg Kroah-Hartman * in use. It also gets called when setup of a device fails. 161596fd7ce5SGreg Kroah-Hartman * 161696fd7ce5SGreg Kroah-Hartman * Locking: 161796fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 161896fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 161996fd7ce5SGreg Kroah-Hartman * 162096fd7ce5SGreg Kroah-Hartman * This method gets called from a work queue so that the driver private 162196fd7ce5SGreg Kroah-Hartman * cleanup ops can sleep (needed for USB at least) 162296fd7ce5SGreg Kroah-Hartman */ 162396fd7ce5SGreg Kroah-Hartman static void release_one_tty(struct work_struct *work) 162496fd7ce5SGreg Kroah-Hartman { 162596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 162696fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 162796fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 1628b216df53SCyrill Gorcunov struct module *owner = driver->owner; 162996fd7ce5SGreg Kroah-Hartman 163096fd7ce5SGreg Kroah-Hartman if (tty->ops->cleanup) 163196fd7ce5SGreg Kroah-Hartman tty->ops->cleanup(tty); 163296fd7ce5SGreg Kroah-Hartman 163396fd7ce5SGreg Kroah-Hartman tty->magic = 0; 163496fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(driver); 1635b216df53SCyrill Gorcunov module_put(owner); 163696fd7ce5SGreg Kroah-Hartman 163796fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 163896fd7ce5SGreg Kroah-Hartman list_del_init(&tty->tty_files); 163996fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 164096fd7ce5SGreg Kroah-Hartman 164196fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 164296fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 164396fd7ce5SGreg Kroah-Hartman free_tty_struct(tty); 164496fd7ce5SGreg Kroah-Hartman } 164596fd7ce5SGreg Kroah-Hartman 164696fd7ce5SGreg Kroah-Hartman static void queue_release_one_tty(struct kref *kref) 164796fd7ce5SGreg Kroah-Hartman { 164896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = container_of(kref, struct tty_struct, kref); 164996fd7ce5SGreg Kroah-Hartman 165096fd7ce5SGreg Kroah-Hartman /* The hangup queue is now free so we can reuse it rather than 165196fd7ce5SGreg Kroah-Hartman waste a chunk of memory for each port */ 165296fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, release_one_tty); 165396fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 165496fd7ce5SGreg Kroah-Hartman } 165596fd7ce5SGreg Kroah-Hartman 165696fd7ce5SGreg Kroah-Hartman /** 165796fd7ce5SGreg Kroah-Hartman * tty_kref_put - release a tty kref 165896fd7ce5SGreg Kroah-Hartman * @tty: tty device 165996fd7ce5SGreg Kroah-Hartman * 166096fd7ce5SGreg Kroah-Hartman * Release a reference to a tty device and if need be let the kref 166196fd7ce5SGreg Kroah-Hartman * layer destruct the object for us 166296fd7ce5SGreg Kroah-Hartman */ 166396fd7ce5SGreg Kroah-Hartman 166496fd7ce5SGreg Kroah-Hartman void tty_kref_put(struct tty_struct *tty) 166596fd7ce5SGreg Kroah-Hartman { 166696fd7ce5SGreg Kroah-Hartman if (tty) 166796fd7ce5SGreg Kroah-Hartman kref_put(&tty->kref, queue_release_one_tty); 166896fd7ce5SGreg Kroah-Hartman } 166996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_kref_put); 167096fd7ce5SGreg Kroah-Hartman 167196fd7ce5SGreg Kroah-Hartman /** 167296fd7ce5SGreg Kroah-Hartman * release_tty - release tty structure memory 167396fd7ce5SGreg Kroah-Hartman * 167496fd7ce5SGreg Kroah-Hartman * Release both @tty and a possible linked partner (think pty pair), 167596fd7ce5SGreg Kroah-Hartman * and decrement the refcount of the backing module. 167696fd7ce5SGreg Kroah-Hartman * 167796fd7ce5SGreg Kroah-Hartman * Locking: 1678d155255aSAlan Cox * tty_mutex 167996fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 168096fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 168196fd7ce5SGreg Kroah-Hartman * 168296fd7ce5SGreg Kroah-Hartman */ 168396fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx) 168496fd7ce5SGreg Kroah-Hartman { 168596fd7ce5SGreg Kroah-Hartman /* This should always be true but check for the moment */ 168696fd7ce5SGreg Kroah-Hartman WARN_ON(tty->index != idx); 1687d155255aSAlan Cox WARN_ON(!mutex_is_locked(&tty_mutex)); 168836b3c070SAlan Cox if (tty->ops->shutdown) 168936b3c070SAlan Cox tty->ops->shutdown(tty); 169036b3c070SAlan Cox tty_free_termios(tty); 169136b3c070SAlan Cox tty_driver_remove_tty(tty->driver, tty); 1692967fab69SJiri Slaby tty->port->itty = NULL; 169364e377dcSPeter Hurley if (tty->link) 169464e377dcSPeter Hurley tty->link->port->itty = NULL; 1695e176058fSPeter Hurley tty_buffer_cancel_work(tty->port); 169636b3c070SAlan Cox 169796fd7ce5SGreg Kroah-Hartman tty_kref_put(tty->link); 169896fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 169996fd7ce5SGreg Kroah-Hartman } 170096fd7ce5SGreg Kroah-Hartman 170196fd7ce5SGreg Kroah-Hartman /** 1702955787caSJiri Slaby * tty_release_checks - check a tty before real release 1703955787caSJiri Slaby * @tty: tty to check 1704955787caSJiri Slaby * @o_tty: link of @tty (if any) 1705955787caSJiri Slaby * @idx: index of the tty 1706955787caSJiri Slaby * 1707955787caSJiri Slaby * Performs some paranoid checking before true release of the @tty. 1708955787caSJiri Slaby * This is a no-op unless TTY_PARANOIA_CHECK is defined. 1709955787caSJiri Slaby */ 1710359b9fb5SPeter Hurley static int tty_release_checks(struct tty_struct *tty, int idx) 1711955787caSJiri Slaby { 1712955787caSJiri Slaby #ifdef TTY_PARANOIA_CHECK 1713955787caSJiri Slaby if (idx < 0 || idx >= tty->driver->num) { 1714e2dfa3d3SPeter Hurley tty_debug(tty, "bad idx %d\n", idx); 1715955787caSJiri Slaby return -1; 1716955787caSJiri Slaby } 1717955787caSJiri Slaby 1718955787caSJiri Slaby /* not much to check for devpts */ 1719955787caSJiri Slaby if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) 1720955787caSJiri Slaby return 0; 1721955787caSJiri Slaby 1722955787caSJiri Slaby if (tty != tty->driver->ttys[idx]) { 1723e2dfa3d3SPeter Hurley tty_debug(tty, "bad driver table[%d] = %p\n", 1724e2dfa3d3SPeter Hurley idx, tty->driver->ttys[idx]); 1725955787caSJiri Slaby return -1; 1726955787caSJiri Slaby } 1727955787caSJiri Slaby if (tty->driver->other) { 1728359b9fb5SPeter Hurley struct tty_struct *o_tty = tty->link; 1729359b9fb5SPeter Hurley 1730955787caSJiri Slaby if (o_tty != tty->driver->other->ttys[idx]) { 1731e2dfa3d3SPeter Hurley tty_debug(tty, "bad other table[%d] = %p\n", 1732e2dfa3d3SPeter Hurley idx, tty->driver->other->ttys[idx]); 1733955787caSJiri Slaby return -1; 1734955787caSJiri Slaby } 1735955787caSJiri Slaby if (o_tty->link != tty) { 1736e2dfa3d3SPeter Hurley tty_debug(tty, "bad link = %p\n", o_tty->link); 1737955787caSJiri Slaby return -1; 1738955787caSJiri Slaby } 1739955787caSJiri Slaby } 1740955787caSJiri Slaby #endif 1741955787caSJiri Slaby return 0; 1742955787caSJiri Slaby } 1743955787caSJiri Slaby 1744955787caSJiri Slaby /** 174596fd7ce5SGreg Kroah-Hartman * tty_release - vfs callback for close 174696fd7ce5SGreg Kroah-Hartman * @inode: inode of tty 174796fd7ce5SGreg Kroah-Hartman * @filp: file pointer for handle to tty 174896fd7ce5SGreg Kroah-Hartman * 174996fd7ce5SGreg Kroah-Hartman * Called the last time each file handle is closed that references 175096fd7ce5SGreg Kroah-Hartman * this tty. There may however be several such references. 175196fd7ce5SGreg Kroah-Hartman * 175296fd7ce5SGreg Kroah-Hartman * Locking: 175396fd7ce5SGreg Kroah-Hartman * Takes bkl. See tty_release_dev 175496fd7ce5SGreg Kroah-Hartman * 175596fd7ce5SGreg Kroah-Hartman * Even releasing the tty structures is a tricky business.. We have 175696fd7ce5SGreg Kroah-Hartman * to be very careful that the structures are all released at the 175796fd7ce5SGreg Kroah-Hartman * same time, as interrupts might otherwise get the wrong pointers. 175896fd7ce5SGreg Kroah-Hartman * 175996fd7ce5SGreg Kroah-Hartman * WSH 09/09/97: rewritten to avoid some nasty race conditions that could 176096fd7ce5SGreg Kroah-Hartman * lead to double frees or releasing memory still in use. 176196fd7ce5SGreg Kroah-Hartman */ 176296fd7ce5SGreg Kroah-Hartman 176396fd7ce5SGreg Kroah-Hartman int tty_release(struct inode *inode, struct file *filp) 176496fd7ce5SGreg Kroah-Hartman { 176596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 17667ffb6da9SPeter Hurley struct tty_struct *o_tty = NULL; 17677ffb6da9SPeter Hurley int do_sleep, final; 176896fd7ce5SGreg Kroah-Hartman int idx; 176937b16457SPeter Hurley long timeout = 0; 1770494c1eacSPeter Hurley int once = 1; 177196fd7ce5SGreg Kroah-Hartman 17729de44bd6SJiri Slaby if (tty_paranoia_check(tty, inode, __func__)) 177396fd7ce5SGreg Kroah-Hartman return 0; 177496fd7ce5SGreg Kroah-Hartman 177589c8d91eSAlan Cox tty_lock(tty); 17769de44bd6SJiri Slaby check_tty_count(tty, __func__); 177796fd7ce5SGreg Kroah-Hartman 177896fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); 177996fd7ce5SGreg Kroah-Hartman 178096fd7ce5SGreg Kroah-Hartman idx = tty->index; 17817ffb6da9SPeter Hurley if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 17827ffb6da9SPeter Hurley tty->driver->subtype == PTY_TYPE_MASTER) 178396fd7ce5SGreg Kroah-Hartman o_tty = tty->link; 178496fd7ce5SGreg Kroah-Hartman 1785359b9fb5SPeter Hurley if (tty_release_checks(tty, idx)) { 178689c8d91eSAlan Cox tty_unlock(tty); 178796fd7ce5SGreg Kroah-Hartman return 0; 178896fd7ce5SGreg Kroah-Hartman } 178996fd7ce5SGreg Kroah-Hartman 1790d435cefeSPeter Hurley tty_debug_hangup(tty, "releasing (count=%d)\n", tty->count); 179196fd7ce5SGreg Kroah-Hartman 179296fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 179396fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, filp); 179496fd7ce5SGreg Kroah-Hartman 17952aff5e2bSPeter Hurley /* If tty is pty master, lock the slave pty (stable lock order) */ 17962aff5e2bSPeter Hurley tty_lock_slave(o_tty); 17972aff5e2bSPeter Hurley 179896fd7ce5SGreg Kroah-Hartman /* 179996fd7ce5SGreg Kroah-Hartman * Sanity check: if tty->count is going to zero, there shouldn't be 180096fd7ce5SGreg Kroah-Hartman * any waiters on tty->read_wait or tty->write_wait. We test the 180196fd7ce5SGreg Kroah-Hartman * wait queues and kick everyone out _before_ actually starting to 180296fd7ce5SGreg Kroah-Hartman * close. This ensures that we won't block while releasing the tty 180396fd7ce5SGreg Kroah-Hartman * structure. 180496fd7ce5SGreg Kroah-Hartman * 180596fd7ce5SGreg Kroah-Hartman * The test for the o_tty closing is necessary, since the master and 180696fd7ce5SGreg Kroah-Hartman * slave sides may close in any order. If the slave side closes out 180796fd7ce5SGreg Kroah-Hartman * first, its count will be one, since the master side holds an open. 1808324c1650SPeter Hurley * Thus this test wouldn't be triggered at the time the slave closed, 180996fd7ce5SGreg Kroah-Hartman * so we do it now. 181096fd7ce5SGreg Kroah-Hartman */ 1811d5e370a4SPeter Hurley while (1) { 181296fd7ce5SGreg Kroah-Hartman do_sleep = 0; 181396fd7ce5SGreg Kroah-Hartman 1814324c1650SPeter Hurley if (tty->count <= 1) { 181596fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->read_wait)) { 181696fd7ce5SGreg Kroah-Hartman wake_up_poll(&tty->read_wait, POLLIN); 181796fd7ce5SGreg Kroah-Hartman do_sleep++; 181896fd7ce5SGreg Kroah-Hartman } 181996fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->write_wait)) { 182096fd7ce5SGreg Kroah-Hartman wake_up_poll(&tty->write_wait, POLLOUT); 182196fd7ce5SGreg Kroah-Hartman do_sleep++; 182296fd7ce5SGreg Kroah-Hartman } 182396fd7ce5SGreg Kroah-Hartman } 18247ffb6da9SPeter Hurley if (o_tty && o_tty->count <= 1) { 182596fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->read_wait)) { 182696fd7ce5SGreg Kroah-Hartman wake_up_poll(&o_tty->read_wait, POLLIN); 182796fd7ce5SGreg Kroah-Hartman do_sleep++; 182896fd7ce5SGreg Kroah-Hartman } 182996fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->write_wait)) { 183096fd7ce5SGreg Kroah-Hartman wake_up_poll(&o_tty->write_wait, POLLOUT); 183196fd7ce5SGreg Kroah-Hartman do_sleep++; 183296fd7ce5SGreg Kroah-Hartman } 183396fd7ce5SGreg Kroah-Hartman } 183496fd7ce5SGreg Kroah-Hartman if (!do_sleep) 183596fd7ce5SGreg Kroah-Hartman break; 183696fd7ce5SGreg Kroah-Hartman 1837494c1eacSPeter Hurley if (once) { 1838494c1eacSPeter Hurley once = 0; 1839339f36baSPeter Hurley tty_warn(tty, "read/write wait queue active!\n"); 1840494c1eacSPeter Hurley } 184137b16457SPeter Hurley schedule_timeout_killable(timeout); 184237b16457SPeter Hurley if (timeout < 120 * HZ) 184337b16457SPeter Hurley timeout = 2 * timeout + 1; 184437b16457SPeter Hurley else 184537b16457SPeter Hurley timeout = MAX_SCHEDULE_TIMEOUT; 184696fd7ce5SGreg Kroah-Hartman } 184796fd7ce5SGreg Kroah-Hartman 18487ffb6da9SPeter Hurley if (o_tty) { 184996fd7ce5SGreg Kroah-Hartman if (--o_tty->count < 0) { 1850339f36baSPeter Hurley tty_warn(tty, "bad slave count (%d)\n", o_tty->count); 185196fd7ce5SGreg Kroah-Hartman o_tty->count = 0; 185296fd7ce5SGreg Kroah-Hartman } 185396fd7ce5SGreg Kroah-Hartman } 185496fd7ce5SGreg Kroah-Hartman if (--tty->count < 0) { 1855339f36baSPeter Hurley tty_warn(tty, "bad tty->count (%d)\n", tty->count); 185696fd7ce5SGreg Kroah-Hartman tty->count = 0; 185796fd7ce5SGreg Kroah-Hartman } 185896fd7ce5SGreg Kroah-Hartman 185996fd7ce5SGreg Kroah-Hartman /* 186096fd7ce5SGreg Kroah-Hartman * We've decremented tty->count, so we need to remove this file 186196fd7ce5SGreg Kroah-Hartman * descriptor off the tty->tty_files list; this serves two 186296fd7ce5SGreg Kroah-Hartman * purposes: 186396fd7ce5SGreg Kroah-Hartman * - check_tty_count sees the correct number of file descriptors 186496fd7ce5SGreg Kroah-Hartman * associated with this tty. 186596fd7ce5SGreg Kroah-Hartman * - do_tty_hangup no longer sees this file descriptor as 186696fd7ce5SGreg Kroah-Hartman * something that needs to be handled for hangups. 186796fd7ce5SGreg Kroah-Hartman */ 186896fd7ce5SGreg Kroah-Hartman tty_del_file(filp); 186996fd7ce5SGreg Kroah-Hartman 187096fd7ce5SGreg Kroah-Hartman /* 187196fd7ce5SGreg Kroah-Hartman * Perform some housekeeping before deciding whether to return. 187296fd7ce5SGreg Kroah-Hartman * 187396fd7ce5SGreg Kroah-Hartman * If _either_ side is closing, make sure there aren't any 187496fd7ce5SGreg Kroah-Hartman * processes that still think tty or o_tty is their controlling 187596fd7ce5SGreg Kroah-Hartman * tty. 187696fd7ce5SGreg Kroah-Hartman */ 1877324c1650SPeter Hurley if (!tty->count) { 187896fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 187996fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 18807ffb6da9SPeter Hurley if (o_tty) 188196fd7ce5SGreg Kroah-Hartman session_clear_tty(o_tty->session); 188296fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 188396fd7ce5SGreg Kroah-Hartman } 188496fd7ce5SGreg Kroah-Hartman 1885324c1650SPeter Hurley /* check whether both sides are closing ... */ 18867ffb6da9SPeter Hurley final = !tty->count && !(o_tty && o_tty->count); 1887324c1650SPeter Hurley 18882aff5e2bSPeter Hurley tty_unlock_slave(o_tty); 18892aff5e2bSPeter Hurley tty_unlock(tty); 18902aff5e2bSPeter Hurley 189104980706SPeter Hurley /* At this point, the tty->count == 0 should ensure a dead tty 1892d155255aSAlan Cox cannot be re-opened by a racing opener */ 189396fd7ce5SGreg Kroah-Hartman 1894324c1650SPeter Hurley if (!final) 189596fd7ce5SGreg Kroah-Hartman return 0; 189696fd7ce5SGreg Kroah-Hartman 1897accff793SPeter Hurley tty_debug_hangup(tty, "final close\n"); 189896fd7ce5SGreg Kroah-Hartman /* 189996fd7ce5SGreg Kroah-Hartman * Ask the line discipline code to release its structures 190096fd7ce5SGreg Kroah-Hartman */ 190162462aefSPeter Hurley tty_ldisc_release(tty); 1902a2965b7bSPeter Hurley 1903a2965b7bSPeter Hurley /* Wait for pending work before tty destruction commmences */ 1904a2965b7bSPeter Hurley tty_flush_works(tty); 1905a2965b7bSPeter Hurley 1906d435cefeSPeter Hurley tty_debug_hangup(tty, "freeing structure\n"); 190796fd7ce5SGreg Kroah-Hartman /* 190896fd7ce5SGreg Kroah-Hartman * The release_tty function takes care of the details of clearing 190989c8d91eSAlan Cox * the slots and preserving the termios structure. The tty_unlock_pair 191089c8d91eSAlan Cox * should be safe as we keep a kref while the tty is locked (so the 191189c8d91eSAlan Cox * unlock never unlocks a freed tty). 191296fd7ce5SGreg Kroah-Hartman */ 1913d155255aSAlan Cox mutex_lock(&tty_mutex); 191496fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 1915d155255aSAlan Cox mutex_unlock(&tty_mutex); 191696fd7ce5SGreg Kroah-Hartman 191796fd7ce5SGreg Kroah-Hartman return 0; 191896fd7ce5SGreg Kroah-Hartman } 191996fd7ce5SGreg Kroah-Hartman 192096fd7ce5SGreg Kroah-Hartman /** 192152494eebSPeter Hurley * tty_open_current_tty - get locked tty of current task 1922b82154acSJiri Slaby * @device: device number 1923b82154acSJiri Slaby * @filp: file pointer to tty 192452494eebSPeter Hurley * @return: locked tty of the current task iff @device is /dev/tty 192552494eebSPeter Hurley * 192652494eebSPeter Hurley * Performs a re-open of the current task's controlling tty. 1927b82154acSJiri Slaby * 1928b82154acSJiri Slaby * We cannot return driver and index like for the other nodes because 1929b82154acSJiri Slaby * devpts will not work then. It expects inodes to be from devpts FS. 1930b82154acSJiri Slaby */ 1931b82154acSJiri Slaby static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) 1932b82154acSJiri Slaby { 1933b82154acSJiri Slaby struct tty_struct *tty; 193452494eebSPeter Hurley int retval; 1935b82154acSJiri Slaby 1936b82154acSJiri Slaby if (device != MKDEV(TTYAUX_MAJOR, 0)) 1937b82154acSJiri Slaby return NULL; 1938b82154acSJiri Slaby 1939b82154acSJiri Slaby tty = get_current_tty(); 1940b82154acSJiri Slaby if (!tty) 1941b82154acSJiri Slaby return ERR_PTR(-ENXIO); 1942b82154acSJiri Slaby 1943b82154acSJiri Slaby filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ 1944b82154acSJiri Slaby /* noctty = 1; */ 194552494eebSPeter Hurley tty_lock(tty); 194652494eebSPeter Hurley tty_kref_put(tty); /* safe to drop the kref now */ 194752494eebSPeter Hurley 194852494eebSPeter Hurley retval = tty_reopen(tty); 194952494eebSPeter Hurley if (retval < 0) { 195052494eebSPeter Hurley tty_unlock(tty); 195152494eebSPeter Hurley tty = ERR_PTR(retval); 195252494eebSPeter Hurley } 1953b82154acSJiri Slaby return tty; 1954b82154acSJiri Slaby } 1955b82154acSJiri Slaby 1956b82154acSJiri Slaby /** 19575b5e7040SJiri Slaby * tty_lookup_driver - lookup a tty driver for a given device file 19585b5e7040SJiri Slaby * @device: device number 19595b5e7040SJiri Slaby * @filp: file pointer to tty 19605b5e7040SJiri Slaby * @noctty: set if the device should not become a controlling tty 19615b5e7040SJiri Slaby * @index: index for the device in the @return driver 19625b5e7040SJiri Slaby * @return: driver for this inode (with increased refcount) 19635b5e7040SJiri Slaby * 19645b5e7040SJiri Slaby * If @return is not erroneous, the caller is responsible to decrement the 19655b5e7040SJiri Slaby * refcount by tty_driver_kref_put. 19665b5e7040SJiri Slaby * 19675b5e7040SJiri Slaby * Locking: tty_mutex protects get_tty_driver 19685b5e7040SJiri Slaby */ 19695b5e7040SJiri Slaby static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp, 19705b5e7040SJiri Slaby int *noctty, int *index) 19715b5e7040SJiri Slaby { 19725b5e7040SJiri Slaby struct tty_driver *driver; 19735b5e7040SJiri Slaby 19742cd0050cSJiri Slaby switch (device) { 19755b5e7040SJiri Slaby #ifdef CONFIG_VT 19762cd0050cSJiri Slaby case MKDEV(TTY_MAJOR, 0): { 19775b5e7040SJiri Slaby extern struct tty_driver *console_driver; 19785b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 19795b5e7040SJiri Slaby *index = fg_console; 19805b5e7040SJiri Slaby *noctty = 1; 19812cd0050cSJiri Slaby break; 19825b5e7040SJiri Slaby } 19835b5e7040SJiri Slaby #endif 19842cd0050cSJiri Slaby case MKDEV(TTYAUX_MAJOR, 1): { 19855b5e7040SJiri Slaby struct tty_driver *console_driver = console_device(index); 19865b5e7040SJiri Slaby if (console_driver) { 19875b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 19885b5e7040SJiri Slaby if (driver) { 19895b5e7040SJiri Slaby /* Don't let /dev/console block */ 19905b5e7040SJiri Slaby filp->f_flags |= O_NONBLOCK; 19915b5e7040SJiri Slaby *noctty = 1; 19922cd0050cSJiri Slaby break; 19935b5e7040SJiri Slaby } 19945b5e7040SJiri Slaby } 19955b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 19965b5e7040SJiri Slaby } 19972cd0050cSJiri Slaby default: 19985b5e7040SJiri Slaby driver = get_tty_driver(device, index); 19995b5e7040SJiri Slaby if (!driver) 20005b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 20012cd0050cSJiri Slaby break; 20022cd0050cSJiri Slaby } 20035b5e7040SJiri Slaby return driver; 20045b5e7040SJiri Slaby } 20055b5e7040SJiri Slaby 20065b5e7040SJiri Slaby /** 200796fd7ce5SGreg Kroah-Hartman * tty_open - open a tty device 200896fd7ce5SGreg Kroah-Hartman * @inode: inode of device file 200996fd7ce5SGreg Kroah-Hartman * @filp: file pointer to tty 201096fd7ce5SGreg Kroah-Hartman * 201196fd7ce5SGreg Kroah-Hartman * tty_open and tty_release keep up the tty count that contains the 201296fd7ce5SGreg Kroah-Hartman * number of opens done on a tty. We cannot use the inode-count, as 201396fd7ce5SGreg Kroah-Hartman * different inodes might point to the same tty. 201496fd7ce5SGreg Kroah-Hartman * 201596fd7ce5SGreg Kroah-Hartman * Open-counting is needed for pty masters, as well as for keeping 201696fd7ce5SGreg Kroah-Hartman * track of serial lines: DTR is dropped when the last close happens. 201796fd7ce5SGreg Kroah-Hartman * (This is not done solely through tty->count, now. - Ted 1/27/92) 201896fd7ce5SGreg Kroah-Hartman * 201996fd7ce5SGreg Kroah-Hartman * The termios state of a pty is reset on first open so that 202096fd7ce5SGreg Kroah-Hartman * settings don't persist across reuse. 202196fd7ce5SGreg Kroah-Hartman * 20225b5e7040SJiri Slaby * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev. 202396fd7ce5SGreg Kroah-Hartman * tty->count should protect the rest. 202496fd7ce5SGreg Kroah-Hartman * ->siglock protects ->signal/->sighand 202589c8d91eSAlan Cox * 202689c8d91eSAlan Cox * Note: the tty_unlock/lock cases without a ref are only safe due to 202789c8d91eSAlan Cox * tty_mutex 202896fd7ce5SGreg Kroah-Hartman */ 202996fd7ce5SGreg Kroah-Hartman 203096fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *inode, struct file *filp) 203196fd7ce5SGreg Kroah-Hartman { 2032b82154acSJiri Slaby struct tty_struct *tty; 203396fd7ce5SGreg Kroah-Hartman int noctty, retval; 2034b82154acSJiri Slaby struct tty_driver *driver = NULL; 203596fd7ce5SGreg Kroah-Hartman int index; 203696fd7ce5SGreg Kroah-Hartman dev_t device = inode->i_rdev; 203796fd7ce5SGreg Kroah-Hartman unsigned saved_flags = filp->f_flags; 203896fd7ce5SGreg Kroah-Hartman 203996fd7ce5SGreg Kroah-Hartman nonseekable_open(inode, filp); 204096fd7ce5SGreg Kroah-Hartman 204196fd7ce5SGreg Kroah-Hartman retry_open: 2042fa90e1c9SJiri Slaby retval = tty_alloc_file(filp); 2043fa90e1c9SJiri Slaby if (retval) 2044fa90e1c9SJiri Slaby return -ENOMEM; 2045fa90e1c9SJiri Slaby 204696fd7ce5SGreg Kroah-Hartman noctty = filp->f_flags & O_NOCTTY; 204796fd7ce5SGreg Kroah-Hartman index = -1; 204896fd7ce5SGreg Kroah-Hartman retval = 0; 204996fd7ce5SGreg Kroah-Hartman 2050b82154acSJiri Slaby tty = tty_open_current_tty(device, filp); 205152494eebSPeter Hurley if (!tty) { 205252494eebSPeter Hurley mutex_lock(&tty_mutex); 20535b5e7040SJiri Slaby driver = tty_lookup_driver(device, filp, &noctty, &index); 20545b5e7040SJiri Slaby if (IS_ERR(driver)) { 2055ba5db448SJiri Slaby retval = PTR_ERR(driver); 2056ba5db448SJiri Slaby goto err_unlock; 205796fd7ce5SGreg Kroah-Hartman } 205896fd7ce5SGreg Kroah-Hartman 205996fd7ce5SGreg Kroah-Hartman /* check whether we're reopening an existing tty */ 206096fd7ce5SGreg Kroah-Hartman tty = tty_driver_lookup_tty(driver, inode, index); 206196fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty)) { 2062ba5db448SJiri Slaby retval = PTR_ERR(tty); 2063ba5db448SJiri Slaby goto err_unlock; 206496fd7ce5SGreg Kroah-Hartman } 206596fd7ce5SGreg Kroah-Hartman 206696fd7ce5SGreg Kroah-Hartman if (tty) { 2067aa3cb814SPeter Hurley mutex_unlock(&tty_mutex); 206889c8d91eSAlan Cox tty_lock(tty); 2069aa3cb814SPeter Hurley /* safe to drop the kref from tty_driver_lookup_tty() */ 2070aa3cb814SPeter Hurley tty_kref_put(tty); 207196fd7ce5SGreg Kroah-Hartman retval = tty_reopen(tty); 207289c8d91eSAlan Cox if (retval < 0) { 207389c8d91eSAlan Cox tty_unlock(tty); 207496fd7ce5SGreg Kroah-Hartman tty = ERR_PTR(retval); 207589c8d91eSAlan Cox } 2076aa3cb814SPeter Hurley } else { /* Returns with the tty_lock held for now */ 2077593a27c4SKonstantin Khlebnikov tty = tty_init_dev(driver, index); 207896fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 2079aa3cb814SPeter Hurley } 2080aa3cb814SPeter Hurley 208196fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(driver); 208252494eebSPeter Hurley } 208352494eebSPeter Hurley 208496fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty)) { 2085ba5db448SJiri Slaby retval = PTR_ERR(tty); 2086ba5db448SJiri Slaby goto err_file; 208796fd7ce5SGreg Kroah-Hartman } 208896fd7ce5SGreg Kroah-Hartman 2089fa90e1c9SJiri Slaby tty_add_file(tty, filp); 209096fd7ce5SGreg Kroah-Hartman 20919de44bd6SJiri Slaby check_tty_count(tty, __func__); 209296fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 209396fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_MASTER) 209496fd7ce5SGreg Kroah-Hartman noctty = 1; 2095accff793SPeter Hurley 2096d435cefeSPeter Hurley tty_debug_hangup(tty, "opening (count=%d)\n", tty->count); 2097accff793SPeter Hurley 209896fd7ce5SGreg Kroah-Hartman if (tty->ops->open) 209996fd7ce5SGreg Kroah-Hartman retval = tty->ops->open(tty, filp); 210096fd7ce5SGreg Kroah-Hartman else 210196fd7ce5SGreg Kroah-Hartman retval = -ENODEV; 210296fd7ce5SGreg Kroah-Hartman filp->f_flags = saved_flags; 210396fd7ce5SGreg Kroah-Hartman 210496fd7ce5SGreg Kroah-Hartman if (retval) { 2105d435cefeSPeter Hurley tty_debug_hangup(tty, "open error %d, releasing\n", retval); 2106accff793SPeter Hurley 210789c8d91eSAlan Cox tty_unlock(tty); /* need to call tty_release without BTM */ 210896fd7ce5SGreg Kroah-Hartman tty_release(inode, filp); 210996fd7ce5SGreg Kroah-Hartman if (retval != -ERESTARTSYS) 211096fd7ce5SGreg Kroah-Hartman return retval; 211196fd7ce5SGreg Kroah-Hartman 211296fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 211396fd7ce5SGreg Kroah-Hartman return retval; 211496fd7ce5SGreg Kroah-Hartman 211596fd7ce5SGreg Kroah-Hartman schedule(); 211696fd7ce5SGreg Kroah-Hartman /* 211796fd7ce5SGreg Kroah-Hartman * Need to reset f_op in case a hangup happened. 211896fd7ce5SGreg Kroah-Hartman */ 21191256937fSPeter Hurley if (tty_hung_up_p(filp)) 212096fd7ce5SGreg Kroah-Hartman filp->f_op = &tty_fops; 212196fd7ce5SGreg Kroah-Hartman goto retry_open; 212296fd7ce5SGreg Kroah-Hartman } 2123d4855e1fSPeter Hurley clear_bit(TTY_HUPPED, &tty->flags); 212496fd7ce5SGreg Kroah-Hartman 212596fd7ce5SGreg Kroah-Hartman 21262c411c11SPeter Hurley read_lock(&tasklist_lock); 212796fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 212896fd7ce5SGreg Kroah-Hartman if (!noctty && 212996fd7ce5SGreg Kroah-Hartman current->signal->leader && 213096fd7ce5SGreg Kroah-Hartman !current->signal->tty && 21310c556271SJann Horn tty->session == NULL) { 21320c556271SJann Horn /* 21330c556271SJann Horn * Don't let a process that only has write access to the tty 21340c556271SJann Horn * obtain the privileges associated with having a tty as 21350c556271SJann Horn * controlling terminal (being able to reopen it with full 21360c556271SJann Horn * access through /dev/tty, being able to perform pushback). 21370c556271SJann Horn * Many distributions set the group of all ttys to "tty" and 21380c556271SJann Horn * grant write-only access to all terminals for setgid tty 21390c556271SJann Horn * binaries, which should not imply full privileges on all ttys. 21400c556271SJann Horn * 21410c556271SJann Horn * This could theoretically break old code that performs open() 21420c556271SJann Horn * on a write-only file descriptor. In that case, it might be 21430c556271SJann Horn * necessary to also permit this if 21440c556271SJann Horn * inode_permission(inode, MAY_READ) == 0. 21450c556271SJann Horn */ 21460c556271SJann Horn if (filp->f_mode & FMODE_READ) 2147bce65f18SPeter Hurley __proc_set_tty(tty); 21480c556271SJann Horn } 214996fd7ce5SGreg Kroah-Hartman spin_unlock_irq(¤t->sighand->siglock); 21502c411c11SPeter Hurley read_unlock(&tasklist_lock); 215189c8d91eSAlan Cox tty_unlock(tty); 215296fd7ce5SGreg Kroah-Hartman return 0; 2153ba5db448SJiri Slaby err_unlock: 2154ba5db448SJiri Slaby mutex_unlock(&tty_mutex); 2155ba5db448SJiri Slaby /* after locks to avoid deadlock */ 2156ba5db448SJiri Slaby if (!IS_ERR_OR_NULL(driver)) 2157ba5db448SJiri Slaby tty_driver_kref_put(driver); 2158ba5db448SJiri Slaby err_file: 2159ba5db448SJiri Slaby tty_free_file(filp); 2160ba5db448SJiri Slaby return retval; 216196fd7ce5SGreg Kroah-Hartman } 216296fd7ce5SGreg Kroah-Hartman 216396fd7ce5SGreg Kroah-Hartman 216496fd7ce5SGreg Kroah-Hartman 216596fd7ce5SGreg Kroah-Hartman /** 216696fd7ce5SGreg Kroah-Hartman * tty_poll - check tty status 216796fd7ce5SGreg Kroah-Hartman * @filp: file being polled 216896fd7ce5SGreg Kroah-Hartman * @wait: poll wait structures to update 216996fd7ce5SGreg Kroah-Hartman * 217096fd7ce5SGreg Kroah-Hartman * Call the line discipline polling method to obtain the poll 217196fd7ce5SGreg Kroah-Hartman * status of the device. 217296fd7ce5SGreg Kroah-Hartman * 217396fd7ce5SGreg Kroah-Hartman * Locking: locks called line discipline but ldisc poll method 217496fd7ce5SGreg Kroah-Hartman * may be re-entered freely by other callers. 217596fd7ce5SGreg Kroah-Hartman */ 217696fd7ce5SGreg Kroah-Hartman 217796fd7ce5SGreg Kroah-Hartman static unsigned int tty_poll(struct file *filp, poll_table *wait) 217896fd7ce5SGreg Kroah-Hartman { 217996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 218096fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 218196fd7ce5SGreg Kroah-Hartman int ret = 0; 218296fd7ce5SGreg Kroah-Hartman 21836131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_poll")) 218496fd7ce5SGreg Kroah-Hartman return 0; 218596fd7ce5SGreg Kroah-Hartman 218696fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 218796fd7ce5SGreg Kroah-Hartman if (ld->ops->poll) 2188c961bfb1SPeter Hurley ret = ld->ops->poll(tty, filp, wait); 218996fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 219096fd7ce5SGreg Kroah-Hartman return ret; 219196fd7ce5SGreg Kroah-Hartman } 219296fd7ce5SGreg Kroah-Hartman 219396fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on) 219496fd7ce5SGreg Kroah-Hartman { 219596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 2196f6c8dbe6SPeter Hurley struct tty_ldisc *ldisc; 219796fd7ce5SGreg Kroah-Hartman unsigned long flags; 219896fd7ce5SGreg Kroah-Hartman int retval = 0; 219996fd7ce5SGreg Kroah-Hartman 22006131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_fasync")) 220196fd7ce5SGreg Kroah-Hartman goto out; 220296fd7ce5SGreg Kroah-Hartman 220396fd7ce5SGreg Kroah-Hartman retval = fasync_helper(fd, filp, on, &tty->fasync); 220496fd7ce5SGreg Kroah-Hartman if (retval <= 0) 220596fd7ce5SGreg Kroah-Hartman goto out; 220696fd7ce5SGreg Kroah-Hartman 2207f6c8dbe6SPeter Hurley ldisc = tty_ldisc_ref(tty); 2208f6c8dbe6SPeter Hurley if (ldisc) { 2209f6c8dbe6SPeter Hurley if (ldisc->ops->fasync) 2210f6c8dbe6SPeter Hurley ldisc->ops->fasync(tty, on); 2211f6c8dbe6SPeter Hurley tty_ldisc_deref(ldisc); 2212f6c8dbe6SPeter Hurley } 2213f6c8dbe6SPeter Hurley 221496fd7ce5SGreg Kroah-Hartman if (on) { 221596fd7ce5SGreg Kroah-Hartman enum pid_type type; 221696fd7ce5SGreg Kroah-Hartman struct pid *pid; 2217f6c8dbe6SPeter Hurley 221896fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 221996fd7ce5SGreg Kroah-Hartman if (tty->pgrp) { 222096fd7ce5SGreg Kroah-Hartman pid = tty->pgrp; 222196fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PGID; 222296fd7ce5SGreg Kroah-Hartman } else { 222396fd7ce5SGreg Kroah-Hartman pid = task_pid(current); 222496fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PID; 222596fd7ce5SGreg Kroah-Hartman } 222696fd7ce5SGreg Kroah-Hartman get_pid(pid); 222796fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 2228e0b93eddSJeff Layton __f_setown(filp, pid, type, 0); 222996fd7ce5SGreg Kroah-Hartman put_pid(pid); 2230e0b93eddSJeff Layton retval = 0; 223196fd7ce5SGreg Kroah-Hartman } 223296fd7ce5SGreg Kroah-Hartman out: 223396fd7ce5SGreg Kroah-Hartman return retval; 223496fd7ce5SGreg Kroah-Hartman } 223596fd7ce5SGreg Kroah-Hartman 223696fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on) 223796fd7ce5SGreg Kroah-Hartman { 223889c8d91eSAlan Cox struct tty_struct *tty = file_tty(filp); 223996fd7ce5SGreg Kroah-Hartman int retval; 224089c8d91eSAlan Cox 224189c8d91eSAlan Cox tty_lock(tty); 224296fd7ce5SGreg Kroah-Hartman retval = __tty_fasync(fd, filp, on); 224389c8d91eSAlan Cox tty_unlock(tty); 224489c8d91eSAlan Cox 224596fd7ce5SGreg Kroah-Hartman return retval; 224696fd7ce5SGreg Kroah-Hartman } 224796fd7ce5SGreg Kroah-Hartman 224896fd7ce5SGreg Kroah-Hartman /** 224996fd7ce5SGreg Kroah-Hartman * tiocsti - fake input character 225096fd7ce5SGreg Kroah-Hartman * @tty: tty to fake input into 225196fd7ce5SGreg Kroah-Hartman * @p: pointer to character 225296fd7ce5SGreg Kroah-Hartman * 225396fd7ce5SGreg Kroah-Hartman * Fake input to a tty device. Does the necessary locking and 225496fd7ce5SGreg Kroah-Hartman * input management. 225596fd7ce5SGreg Kroah-Hartman * 225696fd7ce5SGreg Kroah-Hartman * FIXME: does not honour flow control ?? 225796fd7ce5SGreg Kroah-Hartman * 225896fd7ce5SGreg Kroah-Hartman * Locking: 2259137084bbSPeter Hurley * Called functions take tty_ldiscs_lock 226096fd7ce5SGreg Kroah-Hartman * current->signal->tty check is safe without locks 226196fd7ce5SGreg Kroah-Hartman * 226296fd7ce5SGreg Kroah-Hartman * FIXME: may race normal receive processing 226396fd7ce5SGreg Kroah-Hartman */ 226496fd7ce5SGreg Kroah-Hartman 226596fd7ce5SGreg Kroah-Hartman static int tiocsti(struct tty_struct *tty, char __user *p) 226696fd7ce5SGreg Kroah-Hartman { 226796fd7ce5SGreg Kroah-Hartman char ch, mbz = 0; 226896fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 226996fd7ce5SGreg Kroah-Hartman 227096fd7ce5SGreg Kroah-Hartman if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) 227196fd7ce5SGreg Kroah-Hartman return -EPERM; 227296fd7ce5SGreg Kroah-Hartman if (get_user(ch, p)) 227396fd7ce5SGreg Kroah-Hartman return -EFAULT; 227496fd7ce5SGreg Kroah-Hartman tty_audit_tiocsti(tty, ch); 227596fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 227696fd7ce5SGreg Kroah-Hartman ld->ops->receive_buf(tty, &ch, &mbz, 1); 227796fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 227896fd7ce5SGreg Kroah-Hartman return 0; 227996fd7ce5SGreg Kroah-Hartman } 228096fd7ce5SGreg Kroah-Hartman 228196fd7ce5SGreg Kroah-Hartman /** 228296fd7ce5SGreg Kroah-Hartman * tiocgwinsz - implement window query ioctl 228396fd7ce5SGreg Kroah-Hartman * @tty; tty 228496fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 228596fd7ce5SGreg Kroah-Hartman * 228696fd7ce5SGreg Kroah-Hartman * Copies the kernel idea of the window size into the user buffer. 228796fd7ce5SGreg Kroah-Hartman * 2288dee4a0beSPeter Hurley * Locking: tty->winsize_mutex is taken to ensure the winsize data 228996fd7ce5SGreg Kroah-Hartman * is consistent. 229096fd7ce5SGreg Kroah-Hartman */ 229196fd7ce5SGreg Kroah-Hartman 229296fd7ce5SGreg Kroah-Hartman static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) 229396fd7ce5SGreg Kroah-Hartman { 229496fd7ce5SGreg Kroah-Hartman int err; 229596fd7ce5SGreg Kroah-Hartman 2296dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 229796fd7ce5SGreg Kroah-Hartman err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); 2298dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 229996fd7ce5SGreg Kroah-Hartman 230096fd7ce5SGreg Kroah-Hartman return err ? -EFAULT: 0; 230196fd7ce5SGreg Kroah-Hartman } 230296fd7ce5SGreg Kroah-Hartman 230396fd7ce5SGreg Kroah-Hartman /** 230496fd7ce5SGreg Kroah-Hartman * tty_do_resize - resize event 230596fd7ce5SGreg Kroah-Hartman * @tty: tty being resized 230696fd7ce5SGreg Kroah-Hartman * @rows: rows (character) 230796fd7ce5SGreg Kroah-Hartman * @cols: cols (character) 230896fd7ce5SGreg Kroah-Hartman * 230996fd7ce5SGreg Kroah-Hartman * Update the termios variables and send the necessary signals to 231096fd7ce5SGreg Kroah-Hartman * peform a terminal resize correctly 231196fd7ce5SGreg Kroah-Hartman */ 231296fd7ce5SGreg Kroah-Hartman 231396fd7ce5SGreg Kroah-Hartman int tty_do_resize(struct tty_struct *tty, struct winsize *ws) 231496fd7ce5SGreg Kroah-Hartman { 231596fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 231696fd7ce5SGreg Kroah-Hartman 231796fd7ce5SGreg Kroah-Hartman /* Lock the tty */ 2318dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 231996fd7ce5SGreg Kroah-Hartman if (!memcmp(ws, &tty->winsize, sizeof(*ws))) 232096fd7ce5SGreg Kroah-Hartman goto done; 232196fd7ce5SGreg Kroah-Hartman 23225b239542SPeter Hurley /* Signal the foreground process group */ 23235b239542SPeter Hurley pgrp = tty_get_pgrp(tty); 232496fd7ce5SGreg Kroah-Hartman if (pgrp) 232596fd7ce5SGreg Kroah-Hartman kill_pgrp(pgrp, SIGWINCH, 1); 232696fd7ce5SGreg Kroah-Hartman put_pid(pgrp); 232796fd7ce5SGreg Kroah-Hartman 232896fd7ce5SGreg Kroah-Hartman tty->winsize = *ws; 232996fd7ce5SGreg Kroah-Hartman done: 2330dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 233196fd7ce5SGreg Kroah-Hartman return 0; 233296fd7ce5SGreg Kroah-Hartman } 23334d334fd1SMartin Schwidefsky EXPORT_SYMBOL(tty_do_resize); 233496fd7ce5SGreg Kroah-Hartman 233596fd7ce5SGreg Kroah-Hartman /** 233696fd7ce5SGreg Kroah-Hartman * tiocswinsz - implement window size set ioctl 233796fd7ce5SGreg Kroah-Hartman * @tty; tty side of tty 233896fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 233996fd7ce5SGreg Kroah-Hartman * 234096fd7ce5SGreg Kroah-Hartman * Copies the user idea of the window size to the kernel. Traditionally 234196fd7ce5SGreg Kroah-Hartman * this is just advisory information but for the Linux console it 234296fd7ce5SGreg Kroah-Hartman * actually has driver level meaning and triggers a VC resize. 234396fd7ce5SGreg Kroah-Hartman * 234496fd7ce5SGreg Kroah-Hartman * Locking: 234525985edcSLucas De Marchi * Driver dependent. The default do_resize method takes the 234696fd7ce5SGreg Kroah-Hartman * tty termios mutex and ctrl_lock. The console takes its own lock 234796fd7ce5SGreg Kroah-Hartman * then calls into the default method. 234896fd7ce5SGreg Kroah-Hartman */ 234996fd7ce5SGreg Kroah-Hartman 235096fd7ce5SGreg Kroah-Hartman static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) 235196fd7ce5SGreg Kroah-Hartman { 235296fd7ce5SGreg Kroah-Hartman struct winsize tmp_ws; 235396fd7ce5SGreg Kroah-Hartman if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) 235496fd7ce5SGreg Kroah-Hartman return -EFAULT; 235596fd7ce5SGreg Kroah-Hartman 235696fd7ce5SGreg Kroah-Hartman if (tty->ops->resize) 235796fd7ce5SGreg Kroah-Hartman return tty->ops->resize(tty, &tmp_ws); 235896fd7ce5SGreg Kroah-Hartman else 235996fd7ce5SGreg Kroah-Hartman return tty_do_resize(tty, &tmp_ws); 236096fd7ce5SGreg Kroah-Hartman } 236196fd7ce5SGreg Kroah-Hartman 236296fd7ce5SGreg Kroah-Hartman /** 236396fd7ce5SGreg Kroah-Hartman * tioccons - allow admin to move logical console 236496fd7ce5SGreg Kroah-Hartman * @file: the file to become console 236596fd7ce5SGreg Kroah-Hartman * 236625985edcSLucas De Marchi * Allow the administrator to move the redirected console device 236796fd7ce5SGreg Kroah-Hartman * 236896fd7ce5SGreg Kroah-Hartman * Locking: uses redirect_lock to guard the redirect information 236996fd7ce5SGreg Kroah-Hartman */ 237096fd7ce5SGreg Kroah-Hartman 237196fd7ce5SGreg Kroah-Hartman static int tioccons(struct file *file) 237296fd7ce5SGreg Kroah-Hartman { 237396fd7ce5SGreg Kroah-Hartman if (!capable(CAP_SYS_ADMIN)) 237496fd7ce5SGreg Kroah-Hartman return -EPERM; 237596fd7ce5SGreg Kroah-Hartman if (file->f_op->write == redirected_tty_write) { 237696fd7ce5SGreg Kroah-Hartman struct file *f; 237796fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 237896fd7ce5SGreg Kroah-Hartman f = redirect; 237996fd7ce5SGreg Kroah-Hartman redirect = NULL; 238096fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 238196fd7ce5SGreg Kroah-Hartman if (f) 238296fd7ce5SGreg Kroah-Hartman fput(f); 238396fd7ce5SGreg Kroah-Hartman return 0; 238496fd7ce5SGreg Kroah-Hartman } 238596fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 238696fd7ce5SGreg Kroah-Hartman if (redirect) { 238796fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 238896fd7ce5SGreg Kroah-Hartman return -EBUSY; 238996fd7ce5SGreg Kroah-Hartman } 2390cb0942b8SAl Viro redirect = get_file(file); 239196fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 239296fd7ce5SGreg Kroah-Hartman return 0; 239396fd7ce5SGreg Kroah-Hartman } 239496fd7ce5SGreg Kroah-Hartman 239596fd7ce5SGreg Kroah-Hartman /** 239696fd7ce5SGreg Kroah-Hartman * fionbio - non blocking ioctl 239796fd7ce5SGreg Kroah-Hartman * @file: file to set blocking value 239896fd7ce5SGreg Kroah-Hartman * @p: user parameter 239996fd7ce5SGreg Kroah-Hartman * 240096fd7ce5SGreg Kroah-Hartman * Historical tty interfaces had a blocking control ioctl before 240196fd7ce5SGreg Kroah-Hartman * the generic functionality existed. This piece of history is preserved 240296fd7ce5SGreg Kroah-Hartman * in the expected tty API of posix OS's. 240396fd7ce5SGreg Kroah-Hartman * 240496fd7ce5SGreg Kroah-Hartman * Locking: none, the open file handle ensures it won't go away. 240596fd7ce5SGreg Kroah-Hartman */ 240696fd7ce5SGreg Kroah-Hartman 240796fd7ce5SGreg Kroah-Hartman static int fionbio(struct file *file, int __user *p) 240896fd7ce5SGreg Kroah-Hartman { 240996fd7ce5SGreg Kroah-Hartman int nonblock; 241096fd7ce5SGreg Kroah-Hartman 241196fd7ce5SGreg Kroah-Hartman if (get_user(nonblock, p)) 241296fd7ce5SGreg Kroah-Hartman return -EFAULT; 241396fd7ce5SGreg Kroah-Hartman 241496fd7ce5SGreg Kroah-Hartman spin_lock(&file->f_lock); 241596fd7ce5SGreg Kroah-Hartman if (nonblock) 241696fd7ce5SGreg Kroah-Hartman file->f_flags |= O_NONBLOCK; 241796fd7ce5SGreg Kroah-Hartman else 241896fd7ce5SGreg Kroah-Hartman file->f_flags &= ~O_NONBLOCK; 241996fd7ce5SGreg Kroah-Hartman spin_unlock(&file->f_lock); 242096fd7ce5SGreg Kroah-Hartman return 0; 242196fd7ce5SGreg Kroah-Hartman } 242296fd7ce5SGreg Kroah-Hartman 242396fd7ce5SGreg Kroah-Hartman /** 242496fd7ce5SGreg Kroah-Hartman * tiocsctty - set controlling tty 242596fd7ce5SGreg Kroah-Hartman * @tty: tty structure 242696fd7ce5SGreg Kroah-Hartman * @arg: user argument 242796fd7ce5SGreg Kroah-Hartman * 242896fd7ce5SGreg Kroah-Hartman * This ioctl is used to manage job control. It permits a session 242996fd7ce5SGreg Kroah-Hartman * leader to set this tty as the controlling tty for the session. 243096fd7ce5SGreg Kroah-Hartman * 243196fd7ce5SGreg Kroah-Hartman * Locking: 2432e218eb32SPeter Hurley * Takes tty_lock() to serialize proc_set_tty() for this tty 243396fd7ce5SGreg Kroah-Hartman * Takes tasklist_lock internally to walk sessions 243496fd7ce5SGreg Kroah-Hartman * Takes ->siglock() when updating signal->tty 243596fd7ce5SGreg Kroah-Hartman */ 243696fd7ce5SGreg Kroah-Hartman 24370c556271SJann Horn static int tiocsctty(struct tty_struct *tty, struct file *file, int arg) 243896fd7ce5SGreg Kroah-Hartman { 243996fd7ce5SGreg Kroah-Hartman int ret = 0; 244096fd7ce5SGreg Kroah-Hartman 2441e218eb32SPeter Hurley tty_lock(tty); 24422c411c11SPeter Hurley read_lock(&tasklist_lock); 24432c411c11SPeter Hurley 24442c411c11SPeter Hurley if (current->signal->leader && (task_session(current) == tty->session)) 24452c411c11SPeter Hurley goto unlock; 24462c411c11SPeter Hurley 244796fd7ce5SGreg Kroah-Hartman /* 244896fd7ce5SGreg Kroah-Hartman * The process must be a session leader and 244996fd7ce5SGreg Kroah-Hartman * not have a controlling tty already. 245096fd7ce5SGreg Kroah-Hartman */ 245196fd7ce5SGreg Kroah-Hartman if (!current->signal->leader || current->signal->tty) { 245296fd7ce5SGreg Kroah-Hartman ret = -EPERM; 245396fd7ce5SGreg Kroah-Hartman goto unlock; 245496fd7ce5SGreg Kroah-Hartman } 245596fd7ce5SGreg Kroah-Hartman 245696fd7ce5SGreg Kroah-Hartman if (tty->session) { 245796fd7ce5SGreg Kroah-Hartman /* 245896fd7ce5SGreg Kroah-Hartman * This tty is already the controlling 245996fd7ce5SGreg Kroah-Hartman * tty for another session group! 246096fd7ce5SGreg Kroah-Hartman */ 246196fd7ce5SGreg Kroah-Hartman if (arg == 1 && capable(CAP_SYS_ADMIN)) { 246296fd7ce5SGreg Kroah-Hartman /* 246396fd7ce5SGreg Kroah-Hartman * Steal it away 246496fd7ce5SGreg Kroah-Hartman */ 246596fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 246696fd7ce5SGreg Kroah-Hartman } else { 246796fd7ce5SGreg Kroah-Hartman ret = -EPERM; 246896fd7ce5SGreg Kroah-Hartman goto unlock; 246996fd7ce5SGreg Kroah-Hartman } 247096fd7ce5SGreg Kroah-Hartman } 24710c556271SJann Horn 24720c556271SJann Horn /* See the comment in tty_open(). */ 24730c556271SJann Horn if ((file->f_mode & FMODE_READ) == 0 && !capable(CAP_SYS_ADMIN)) { 24740c556271SJann Horn ret = -EPERM; 24750c556271SJann Horn goto unlock; 24760c556271SJann Horn } 24770c556271SJann Horn 2478bce65f18SPeter Hurley proc_set_tty(tty); 247996fd7ce5SGreg Kroah-Hartman unlock: 24802c411c11SPeter Hurley read_unlock(&tasklist_lock); 2481e218eb32SPeter Hurley tty_unlock(tty); 248296fd7ce5SGreg Kroah-Hartman return ret; 248396fd7ce5SGreg Kroah-Hartman } 248496fd7ce5SGreg Kroah-Hartman 248596fd7ce5SGreg Kroah-Hartman /** 248696fd7ce5SGreg Kroah-Hartman * tty_get_pgrp - return a ref counted pgrp pid 248796fd7ce5SGreg Kroah-Hartman * @tty: tty to read 248896fd7ce5SGreg Kroah-Hartman * 248996fd7ce5SGreg Kroah-Hartman * Returns a refcounted instance of the pid struct for the process 249096fd7ce5SGreg Kroah-Hartman * group controlling the tty. 249196fd7ce5SGreg Kroah-Hartman */ 249296fd7ce5SGreg Kroah-Hartman 249396fd7ce5SGreg Kroah-Hartman struct pid *tty_get_pgrp(struct tty_struct *tty) 249496fd7ce5SGreg Kroah-Hartman { 249596fd7ce5SGreg Kroah-Hartman unsigned long flags; 249696fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 249796fd7ce5SGreg Kroah-Hartman 249896fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 249996fd7ce5SGreg Kroah-Hartman pgrp = get_pid(tty->pgrp); 250096fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 250196fd7ce5SGreg Kroah-Hartman 250296fd7ce5SGreg Kroah-Hartman return pgrp; 250396fd7ce5SGreg Kroah-Hartman } 250496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_get_pgrp); 250596fd7ce5SGreg Kroah-Hartman 2506e1c2296cSPeter Hurley /* 2507e1c2296cSPeter Hurley * This checks not only the pgrp, but falls back on the pid if no 2508e1c2296cSPeter Hurley * satisfactory pgrp is found. I dunno - gdb doesn't work correctly 2509e1c2296cSPeter Hurley * without this... 2510e1c2296cSPeter Hurley * 2511e1c2296cSPeter Hurley * The caller must hold rcu lock or the tasklist lock. 2512e1c2296cSPeter Hurley */ 2513e1c2296cSPeter Hurley static struct pid *session_of_pgrp(struct pid *pgrp) 2514e1c2296cSPeter Hurley { 2515e1c2296cSPeter Hurley struct task_struct *p; 2516e1c2296cSPeter Hurley struct pid *sid = NULL; 2517e1c2296cSPeter Hurley 2518e1c2296cSPeter Hurley p = pid_task(pgrp, PIDTYPE_PGID); 2519e1c2296cSPeter Hurley if (p == NULL) 2520e1c2296cSPeter Hurley p = pid_task(pgrp, PIDTYPE_PID); 2521e1c2296cSPeter Hurley if (p != NULL) 2522e1c2296cSPeter Hurley sid = task_session(p); 2523e1c2296cSPeter Hurley 2524e1c2296cSPeter Hurley return sid; 2525e1c2296cSPeter Hurley } 2526e1c2296cSPeter Hurley 252796fd7ce5SGreg Kroah-Hartman /** 252896fd7ce5SGreg Kroah-Hartman * tiocgpgrp - get process group 252996fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 253025985edcSLucas De Marchi * @real_tty: tty side of the tty passed by the user if a pty else the tty 253196fd7ce5SGreg Kroah-Hartman * @p: returned pid 253296fd7ce5SGreg Kroah-Hartman * 253396fd7ce5SGreg Kroah-Hartman * Obtain the process group of the tty. If there is no process group 253496fd7ce5SGreg Kroah-Hartman * return an error. 253596fd7ce5SGreg Kroah-Hartman * 253696fd7ce5SGreg Kroah-Hartman * Locking: none. Reference to current->signal->tty is safe. 253796fd7ce5SGreg Kroah-Hartman */ 253896fd7ce5SGreg Kroah-Hartman 253996fd7ce5SGreg Kroah-Hartman static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 254096fd7ce5SGreg Kroah-Hartman { 254196fd7ce5SGreg Kroah-Hartman struct pid *pid; 254296fd7ce5SGreg Kroah-Hartman int ret; 254396fd7ce5SGreg Kroah-Hartman /* 254496fd7ce5SGreg Kroah-Hartman * (tty == real_tty) is a cheap way of 254596fd7ce5SGreg Kroah-Hartman * testing if the tty is NOT a master pty. 254696fd7ce5SGreg Kroah-Hartman */ 254796fd7ce5SGreg Kroah-Hartman if (tty == real_tty && current->signal->tty != real_tty) 254896fd7ce5SGreg Kroah-Hartman return -ENOTTY; 254996fd7ce5SGreg Kroah-Hartman pid = tty_get_pgrp(real_tty); 255096fd7ce5SGreg Kroah-Hartman ret = put_user(pid_vnr(pid), p); 255196fd7ce5SGreg Kroah-Hartman put_pid(pid); 255296fd7ce5SGreg Kroah-Hartman return ret; 255396fd7ce5SGreg Kroah-Hartman } 255496fd7ce5SGreg Kroah-Hartman 255596fd7ce5SGreg Kroah-Hartman /** 255696fd7ce5SGreg Kroah-Hartman * tiocspgrp - attempt to set process group 255796fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 255896fd7ce5SGreg Kroah-Hartman * @real_tty: tty side device matching tty passed by user 255996fd7ce5SGreg Kroah-Hartman * @p: pid pointer 256096fd7ce5SGreg Kroah-Hartman * 256196fd7ce5SGreg Kroah-Hartman * Set the process group of the tty to the session passed. Only 256296fd7ce5SGreg Kroah-Hartman * permitted where the tty session is our session. 256396fd7ce5SGreg Kroah-Hartman * 256496fd7ce5SGreg Kroah-Hartman * Locking: RCU, ctrl lock 256596fd7ce5SGreg Kroah-Hartman */ 256696fd7ce5SGreg Kroah-Hartman 256796fd7ce5SGreg Kroah-Hartman static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 256896fd7ce5SGreg Kroah-Hartman { 256996fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 257096fd7ce5SGreg Kroah-Hartman pid_t pgrp_nr; 257196fd7ce5SGreg Kroah-Hartman int retval = tty_check_change(real_tty); 257296fd7ce5SGreg Kroah-Hartman 257396fd7ce5SGreg Kroah-Hartman if (retval == -EIO) 257496fd7ce5SGreg Kroah-Hartman return -ENOTTY; 257596fd7ce5SGreg Kroah-Hartman if (retval) 257696fd7ce5SGreg Kroah-Hartman return retval; 257796fd7ce5SGreg Kroah-Hartman if (!current->signal->tty || 257896fd7ce5SGreg Kroah-Hartman (current->signal->tty != real_tty) || 257996fd7ce5SGreg Kroah-Hartman (real_tty->session != task_session(current))) 258096fd7ce5SGreg Kroah-Hartman return -ENOTTY; 258196fd7ce5SGreg Kroah-Hartman if (get_user(pgrp_nr, p)) 258296fd7ce5SGreg Kroah-Hartman return -EFAULT; 258396fd7ce5SGreg Kroah-Hartman if (pgrp_nr < 0) 258496fd7ce5SGreg Kroah-Hartman return -EINVAL; 258596fd7ce5SGreg Kroah-Hartman rcu_read_lock(); 258696fd7ce5SGreg Kroah-Hartman pgrp = find_vpid(pgrp_nr); 258796fd7ce5SGreg Kroah-Hartman retval = -ESRCH; 258896fd7ce5SGreg Kroah-Hartman if (!pgrp) 258996fd7ce5SGreg Kroah-Hartman goto out_unlock; 259096fd7ce5SGreg Kroah-Hartman retval = -EPERM; 259196fd7ce5SGreg Kroah-Hartman if (session_of_pgrp(pgrp) != task_session(current)) 259296fd7ce5SGreg Kroah-Hartman goto out_unlock; 259396fd7ce5SGreg Kroah-Hartman retval = 0; 25941e86b5bfSPeter Hurley spin_lock_irq(&tty->ctrl_lock); 259596fd7ce5SGreg Kroah-Hartman put_pid(real_tty->pgrp); 259696fd7ce5SGreg Kroah-Hartman real_tty->pgrp = get_pid(pgrp); 25971e86b5bfSPeter Hurley spin_unlock_irq(&tty->ctrl_lock); 259896fd7ce5SGreg Kroah-Hartman out_unlock: 259996fd7ce5SGreg Kroah-Hartman rcu_read_unlock(); 260096fd7ce5SGreg Kroah-Hartman return retval; 260196fd7ce5SGreg Kroah-Hartman } 260296fd7ce5SGreg Kroah-Hartman 260396fd7ce5SGreg Kroah-Hartman /** 260496fd7ce5SGreg Kroah-Hartman * tiocgsid - get session id 260596fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 260625985edcSLucas De Marchi * @real_tty: tty side of the tty passed by the user if a pty else the tty 260796fd7ce5SGreg Kroah-Hartman * @p: pointer to returned session id 260896fd7ce5SGreg Kroah-Hartman * 260996fd7ce5SGreg Kroah-Hartman * Obtain the session id of the tty. If there is no session 261096fd7ce5SGreg Kroah-Hartman * return an error. 261196fd7ce5SGreg Kroah-Hartman * 261296fd7ce5SGreg Kroah-Hartman * Locking: none. Reference to current->signal->tty is safe. 261396fd7ce5SGreg Kroah-Hartman */ 261496fd7ce5SGreg Kroah-Hartman 261596fd7ce5SGreg Kroah-Hartman static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 261696fd7ce5SGreg Kroah-Hartman { 261796fd7ce5SGreg Kroah-Hartman /* 261896fd7ce5SGreg Kroah-Hartman * (tty == real_tty) is a cheap way of 261996fd7ce5SGreg Kroah-Hartman * testing if the tty is NOT a master pty. 262096fd7ce5SGreg Kroah-Hartman */ 262196fd7ce5SGreg Kroah-Hartman if (tty == real_tty && current->signal->tty != real_tty) 262296fd7ce5SGreg Kroah-Hartman return -ENOTTY; 262396fd7ce5SGreg Kroah-Hartman if (!real_tty->session) 262496fd7ce5SGreg Kroah-Hartman return -ENOTTY; 262596fd7ce5SGreg Kroah-Hartman return put_user(pid_vnr(real_tty->session), p); 262696fd7ce5SGreg Kroah-Hartman } 262796fd7ce5SGreg Kroah-Hartman 262896fd7ce5SGreg Kroah-Hartman /** 262996fd7ce5SGreg Kroah-Hartman * tiocsetd - set line discipline 263096fd7ce5SGreg Kroah-Hartman * @tty: tty device 263196fd7ce5SGreg Kroah-Hartman * @p: pointer to user data 263296fd7ce5SGreg Kroah-Hartman * 263396fd7ce5SGreg Kroah-Hartman * Set the line discipline according to user request. 263496fd7ce5SGreg Kroah-Hartman * 263596fd7ce5SGreg Kroah-Hartman * Locking: see tty_set_ldisc, this function is just a helper 263696fd7ce5SGreg Kroah-Hartman */ 263796fd7ce5SGreg Kroah-Hartman 263896fd7ce5SGreg Kroah-Hartman static int tiocsetd(struct tty_struct *tty, int __user *p) 263996fd7ce5SGreg Kroah-Hartman { 264096fd7ce5SGreg Kroah-Hartman int ldisc; 264196fd7ce5SGreg Kroah-Hartman int ret; 264296fd7ce5SGreg Kroah-Hartman 264396fd7ce5SGreg Kroah-Hartman if (get_user(ldisc, p)) 264496fd7ce5SGreg Kroah-Hartman return -EFAULT; 264596fd7ce5SGreg Kroah-Hartman 264696fd7ce5SGreg Kroah-Hartman ret = tty_set_ldisc(tty, ldisc); 264796fd7ce5SGreg Kroah-Hartman 264896fd7ce5SGreg Kroah-Hartman return ret; 264996fd7ce5SGreg Kroah-Hartman } 265096fd7ce5SGreg Kroah-Hartman 265196fd7ce5SGreg Kroah-Hartman /** 265296fd7ce5SGreg Kroah-Hartman * send_break - performed time break 265396fd7ce5SGreg Kroah-Hartman * @tty: device to break on 265496fd7ce5SGreg Kroah-Hartman * @duration: timeout in mS 265596fd7ce5SGreg Kroah-Hartman * 265696fd7ce5SGreg Kroah-Hartman * Perform a timed break on hardware that lacks its own driver level 265796fd7ce5SGreg Kroah-Hartman * timed break functionality. 265896fd7ce5SGreg Kroah-Hartman * 265996fd7ce5SGreg Kroah-Hartman * Locking: 266096fd7ce5SGreg Kroah-Hartman * atomic_write_lock serializes 266196fd7ce5SGreg Kroah-Hartman * 266296fd7ce5SGreg Kroah-Hartman */ 266396fd7ce5SGreg Kroah-Hartman 266496fd7ce5SGreg Kroah-Hartman static int send_break(struct tty_struct *tty, unsigned int duration) 266596fd7ce5SGreg Kroah-Hartman { 266696fd7ce5SGreg Kroah-Hartman int retval; 266796fd7ce5SGreg Kroah-Hartman 266896fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl == NULL) 266996fd7ce5SGreg Kroah-Hartman return 0; 267096fd7ce5SGreg Kroah-Hartman 267196fd7ce5SGreg Kroah-Hartman if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) 267296fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, duration); 267396fd7ce5SGreg Kroah-Hartman else { 267496fd7ce5SGreg Kroah-Hartman /* Do the work ourselves */ 267596fd7ce5SGreg Kroah-Hartman if (tty_write_lock(tty, 0) < 0) 267696fd7ce5SGreg Kroah-Hartman return -EINTR; 267796fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, -1); 267896fd7ce5SGreg Kroah-Hartman if (retval) 267996fd7ce5SGreg Kroah-Hartman goto out; 268096fd7ce5SGreg Kroah-Hartman if (!signal_pending(current)) 268196fd7ce5SGreg Kroah-Hartman msleep_interruptible(duration); 268296fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, 0); 268396fd7ce5SGreg Kroah-Hartman out: 268496fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 268596fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 268696fd7ce5SGreg Kroah-Hartman retval = -EINTR; 268796fd7ce5SGreg Kroah-Hartman } 268896fd7ce5SGreg Kroah-Hartman return retval; 268996fd7ce5SGreg Kroah-Hartman } 269096fd7ce5SGreg Kroah-Hartman 269196fd7ce5SGreg Kroah-Hartman /** 269296fd7ce5SGreg Kroah-Hartman * tty_tiocmget - get modem status 269396fd7ce5SGreg Kroah-Hartman * @tty: tty device 269496fd7ce5SGreg Kroah-Hartman * @file: user file pointer 269596fd7ce5SGreg Kroah-Hartman * @p: pointer to result 269696fd7ce5SGreg Kroah-Hartman * 269796fd7ce5SGreg Kroah-Hartman * Obtain the modem status bits from the tty driver if the feature 269896fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 269996fd7ce5SGreg Kroah-Hartman * 270096fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 270196fd7ce5SGreg Kroah-Hartman */ 270296fd7ce5SGreg Kroah-Hartman 270360b33c13SAlan Cox static int tty_tiocmget(struct tty_struct *tty, int __user *p) 270496fd7ce5SGreg Kroah-Hartman { 270596fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 270696fd7ce5SGreg Kroah-Hartman 270796fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmget) { 270860b33c13SAlan Cox retval = tty->ops->tiocmget(tty); 270996fd7ce5SGreg Kroah-Hartman 271096fd7ce5SGreg Kroah-Hartman if (retval >= 0) 271196fd7ce5SGreg Kroah-Hartman retval = put_user(retval, p); 271296fd7ce5SGreg Kroah-Hartman } 271396fd7ce5SGreg Kroah-Hartman return retval; 271496fd7ce5SGreg Kroah-Hartman } 271596fd7ce5SGreg Kroah-Hartman 271696fd7ce5SGreg Kroah-Hartman /** 271796fd7ce5SGreg Kroah-Hartman * tty_tiocmset - set modem status 271896fd7ce5SGreg Kroah-Hartman * @tty: tty device 271996fd7ce5SGreg Kroah-Hartman * @cmd: command - clear bits, set bits or set all 272096fd7ce5SGreg Kroah-Hartman * @p: pointer to desired bits 272196fd7ce5SGreg Kroah-Hartman * 272296fd7ce5SGreg Kroah-Hartman * Set the modem status bits from the tty driver if the feature 272396fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 272496fd7ce5SGreg Kroah-Hartman * 272596fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 272696fd7ce5SGreg Kroah-Hartman */ 272796fd7ce5SGreg Kroah-Hartman 272820b9d177SAlan Cox static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, 272996fd7ce5SGreg Kroah-Hartman unsigned __user *p) 273096fd7ce5SGreg Kroah-Hartman { 273196fd7ce5SGreg Kroah-Hartman int retval; 273296fd7ce5SGreg Kroah-Hartman unsigned int set, clear, val; 273396fd7ce5SGreg Kroah-Hartman 273496fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmset == NULL) 273596fd7ce5SGreg Kroah-Hartman return -EINVAL; 273696fd7ce5SGreg Kroah-Hartman 273796fd7ce5SGreg Kroah-Hartman retval = get_user(val, p); 273896fd7ce5SGreg Kroah-Hartman if (retval) 273996fd7ce5SGreg Kroah-Hartman return retval; 274096fd7ce5SGreg Kroah-Hartman set = clear = 0; 274196fd7ce5SGreg Kroah-Hartman switch (cmd) { 274296fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 274396fd7ce5SGreg Kroah-Hartman set = val; 274496fd7ce5SGreg Kroah-Hartman break; 274596fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 274696fd7ce5SGreg Kroah-Hartman clear = val; 274796fd7ce5SGreg Kroah-Hartman break; 274896fd7ce5SGreg Kroah-Hartman case TIOCMSET: 274996fd7ce5SGreg Kroah-Hartman set = val; 275096fd7ce5SGreg Kroah-Hartman clear = ~val; 275196fd7ce5SGreg Kroah-Hartman break; 275296fd7ce5SGreg Kroah-Hartman } 275396fd7ce5SGreg Kroah-Hartman set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 275496fd7ce5SGreg Kroah-Hartman clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 275520b9d177SAlan Cox return tty->ops->tiocmset(tty, set, clear); 275696fd7ce5SGreg Kroah-Hartman } 275796fd7ce5SGreg Kroah-Hartman 275896fd7ce5SGreg Kroah-Hartman static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) 275996fd7ce5SGreg Kroah-Hartman { 276096fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 276196fd7ce5SGreg Kroah-Hartman struct serial_icounter_struct icount; 276296fd7ce5SGreg Kroah-Hartman memset(&icount, 0, sizeof(icount)); 276396fd7ce5SGreg Kroah-Hartman if (tty->ops->get_icount) 276496fd7ce5SGreg Kroah-Hartman retval = tty->ops->get_icount(tty, &icount); 276596fd7ce5SGreg Kroah-Hartman if (retval != 0) 276696fd7ce5SGreg Kroah-Hartman return retval; 276796fd7ce5SGreg Kroah-Hartman if (copy_to_user(arg, &icount, sizeof(icount))) 276896fd7ce5SGreg Kroah-Hartman return -EFAULT; 276996fd7ce5SGreg Kroah-Hartman return 0; 277096fd7ce5SGreg Kroah-Hartman } 277196fd7ce5SGreg Kroah-Hartman 27728a8ae62fSJiri Slaby static void tty_warn_deprecated_flags(struct serial_struct __user *ss) 27738a8ae62fSJiri Slaby { 27748a8ae62fSJiri Slaby static DEFINE_RATELIMIT_STATE(depr_flags, 27758a8ae62fSJiri Slaby DEFAULT_RATELIMIT_INTERVAL, 27768a8ae62fSJiri Slaby DEFAULT_RATELIMIT_BURST); 27778a8ae62fSJiri Slaby char comm[TASK_COMM_LEN]; 27788a8ae62fSJiri Slaby int flags; 27798a8ae62fSJiri Slaby 27808a8ae62fSJiri Slaby if (get_user(flags, &ss->flags)) 27818a8ae62fSJiri Slaby return; 27828a8ae62fSJiri Slaby 27838a8ae62fSJiri Slaby flags &= ASYNC_DEPRECATED; 27848a8ae62fSJiri Slaby 27858a8ae62fSJiri Slaby if (flags && __ratelimit(&depr_flags)) 27868a8ae62fSJiri Slaby pr_warning("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", 27878a8ae62fSJiri Slaby __func__, get_task_comm(comm, current), flags); 27888a8ae62fSJiri Slaby } 27898a8ae62fSJiri Slaby 27908f166e00SPeter Hurley /* 27918f166e00SPeter Hurley * if pty, return the slave side (real_tty) 27928f166e00SPeter Hurley * otherwise, return self 27938f166e00SPeter Hurley */ 27948f166e00SPeter Hurley static struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) 279596fd7ce5SGreg Kroah-Hartman { 279696fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 279796fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_MASTER) 279896fd7ce5SGreg Kroah-Hartman tty = tty->link; 279996fd7ce5SGreg Kroah-Hartman return tty; 280096fd7ce5SGreg Kroah-Hartman } 280196fd7ce5SGreg Kroah-Hartman 280296fd7ce5SGreg Kroah-Hartman /* 280396fd7ce5SGreg Kroah-Hartman * Split this up, as gcc can choke on it otherwise.. 280496fd7ce5SGreg Kroah-Hartman */ 280596fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 280696fd7ce5SGreg Kroah-Hartman { 280796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 280896fd7ce5SGreg Kroah-Hartman struct tty_struct *real_tty; 280996fd7ce5SGreg Kroah-Hartman void __user *p = (void __user *)arg; 281096fd7ce5SGreg Kroah-Hartman int retval; 281196fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 281296fd7ce5SGreg Kroah-Hartman 28136131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 281496fd7ce5SGreg Kroah-Hartman return -EINVAL; 281596fd7ce5SGreg Kroah-Hartman 281696fd7ce5SGreg Kroah-Hartman real_tty = tty_pair_get_tty(tty); 281796fd7ce5SGreg Kroah-Hartman 281896fd7ce5SGreg Kroah-Hartman /* 281996fd7ce5SGreg Kroah-Hartman * Factor out some common prep work 282096fd7ce5SGreg Kroah-Hartman */ 282196fd7ce5SGreg Kroah-Hartman switch (cmd) { 282296fd7ce5SGreg Kroah-Hartman case TIOCSETD: 282396fd7ce5SGreg Kroah-Hartman case TIOCSBRK: 282496fd7ce5SGreg Kroah-Hartman case TIOCCBRK: 282596fd7ce5SGreg Kroah-Hartman case TCSBRK: 282696fd7ce5SGreg Kroah-Hartman case TCSBRKP: 282796fd7ce5SGreg Kroah-Hartman retval = tty_check_change(tty); 282896fd7ce5SGreg Kroah-Hartman if (retval) 282996fd7ce5SGreg Kroah-Hartman return retval; 283096fd7ce5SGreg Kroah-Hartman if (cmd != TIOCCBRK) { 283196fd7ce5SGreg Kroah-Hartman tty_wait_until_sent(tty, 0); 283296fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 283396fd7ce5SGreg Kroah-Hartman return -EINTR; 283496fd7ce5SGreg Kroah-Hartman } 283596fd7ce5SGreg Kroah-Hartman break; 283696fd7ce5SGreg Kroah-Hartman } 283796fd7ce5SGreg Kroah-Hartman 283896fd7ce5SGreg Kroah-Hartman /* 283996fd7ce5SGreg Kroah-Hartman * Now do the stuff. 284096fd7ce5SGreg Kroah-Hartman */ 284196fd7ce5SGreg Kroah-Hartman switch (cmd) { 284296fd7ce5SGreg Kroah-Hartman case TIOCSTI: 284396fd7ce5SGreg Kroah-Hartman return tiocsti(tty, p); 284496fd7ce5SGreg Kroah-Hartman case TIOCGWINSZ: 284596fd7ce5SGreg Kroah-Hartman return tiocgwinsz(real_tty, p); 284696fd7ce5SGreg Kroah-Hartman case TIOCSWINSZ: 284796fd7ce5SGreg Kroah-Hartman return tiocswinsz(real_tty, p); 284896fd7ce5SGreg Kroah-Hartman case TIOCCONS: 284996fd7ce5SGreg Kroah-Hartman return real_tty != tty ? -EINVAL : tioccons(file); 285096fd7ce5SGreg Kroah-Hartman case FIONBIO: 285196fd7ce5SGreg Kroah-Hartman return fionbio(file, p); 285296fd7ce5SGreg Kroah-Hartman case TIOCEXCL: 285396fd7ce5SGreg Kroah-Hartman set_bit(TTY_EXCLUSIVE, &tty->flags); 285496fd7ce5SGreg Kroah-Hartman return 0; 285596fd7ce5SGreg Kroah-Hartman case TIOCNXCL: 285696fd7ce5SGreg Kroah-Hartman clear_bit(TTY_EXCLUSIVE, &tty->flags); 285796fd7ce5SGreg Kroah-Hartman return 0; 285884fd7bdfSCyrill Gorcunov case TIOCGEXCL: 285984fd7bdfSCyrill Gorcunov { 286084fd7bdfSCyrill Gorcunov int excl = test_bit(TTY_EXCLUSIVE, &tty->flags); 286184fd7bdfSCyrill Gorcunov return put_user(excl, (int __user *)p); 286284fd7bdfSCyrill Gorcunov } 286396fd7ce5SGreg Kroah-Hartman case TIOCNOTTY: 286496fd7ce5SGreg Kroah-Hartman if (current->signal->tty != tty) 286596fd7ce5SGreg Kroah-Hartman return -ENOTTY; 286696fd7ce5SGreg Kroah-Hartman no_tty(); 286796fd7ce5SGreg Kroah-Hartman return 0; 286896fd7ce5SGreg Kroah-Hartman case TIOCSCTTY: 28690c556271SJann Horn return tiocsctty(tty, file, arg); 287096fd7ce5SGreg Kroah-Hartman case TIOCGPGRP: 287196fd7ce5SGreg Kroah-Hartman return tiocgpgrp(tty, real_tty, p); 287296fd7ce5SGreg Kroah-Hartman case TIOCSPGRP: 287396fd7ce5SGreg Kroah-Hartman return tiocspgrp(tty, real_tty, p); 287496fd7ce5SGreg Kroah-Hartman case TIOCGSID: 287596fd7ce5SGreg Kroah-Hartman return tiocgsid(tty, real_tty, p); 287696fd7ce5SGreg Kroah-Hartman case TIOCGETD: 287796fd7ce5SGreg Kroah-Hartman return put_user(tty->ldisc->ops->num, (int __user *)p); 287896fd7ce5SGreg Kroah-Hartman case TIOCSETD: 287996fd7ce5SGreg Kroah-Hartman return tiocsetd(tty, p); 28803c95c985SKay Sievers case TIOCVHANGUP: 28813c95c985SKay Sievers if (!capable(CAP_SYS_ADMIN)) 28823c95c985SKay Sievers return -EPERM; 28833c95c985SKay Sievers tty_vhangup(tty); 28843c95c985SKay Sievers return 0; 2885b7b8de08SWerner Fink case TIOCGDEV: 2886b7b8de08SWerner Fink { 2887b7b8de08SWerner Fink unsigned int ret = new_encode_dev(tty_devnum(real_tty)); 2888b7b8de08SWerner Fink return put_user(ret, (unsigned int __user *)p); 2889b7b8de08SWerner Fink } 289096fd7ce5SGreg Kroah-Hartman /* 289196fd7ce5SGreg Kroah-Hartman * Break handling 289296fd7ce5SGreg Kroah-Hartman */ 289396fd7ce5SGreg Kroah-Hartman case TIOCSBRK: /* Turn break on, unconditionally */ 289496fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 289596fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, -1); 289696fd7ce5SGreg Kroah-Hartman return 0; 289796fd7ce5SGreg Kroah-Hartman case TIOCCBRK: /* Turn break off, unconditionally */ 289896fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 289996fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, 0); 290096fd7ce5SGreg Kroah-Hartman return 0; 290196fd7ce5SGreg Kroah-Hartman case TCSBRK: /* SVID version: non-zero arg --> no break */ 290296fd7ce5SGreg Kroah-Hartman /* non-zero arg means wait for all output data 290396fd7ce5SGreg Kroah-Hartman * to be sent (performed above) but don't send break. 290496fd7ce5SGreg Kroah-Hartman * This is used by the tcdrain() termios function. 290596fd7ce5SGreg Kroah-Hartman */ 290696fd7ce5SGreg Kroah-Hartman if (!arg) 290796fd7ce5SGreg Kroah-Hartman return send_break(tty, 250); 290896fd7ce5SGreg Kroah-Hartman return 0; 290996fd7ce5SGreg Kroah-Hartman case TCSBRKP: /* support for POSIX tcsendbreak() */ 291096fd7ce5SGreg Kroah-Hartman return send_break(tty, arg ? arg*100 : 250); 291196fd7ce5SGreg Kroah-Hartman 291296fd7ce5SGreg Kroah-Hartman case TIOCMGET: 291360b33c13SAlan Cox return tty_tiocmget(tty, p); 291496fd7ce5SGreg Kroah-Hartman case TIOCMSET: 291596fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 291696fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 291720b9d177SAlan Cox return tty_tiocmset(tty, cmd, p); 291896fd7ce5SGreg Kroah-Hartman case TIOCGICOUNT: 291996fd7ce5SGreg Kroah-Hartman retval = tty_tiocgicount(tty, p); 292096fd7ce5SGreg Kroah-Hartman /* For the moment allow fall through to the old method */ 292196fd7ce5SGreg Kroah-Hartman if (retval != -EINVAL) 292296fd7ce5SGreg Kroah-Hartman return retval; 292396fd7ce5SGreg Kroah-Hartman break; 292496fd7ce5SGreg Kroah-Hartman case TCFLSH: 292596fd7ce5SGreg Kroah-Hartman switch (arg) { 292696fd7ce5SGreg Kroah-Hartman case TCIFLUSH: 292796fd7ce5SGreg Kroah-Hartman case TCIOFLUSH: 292896fd7ce5SGreg Kroah-Hartman /* flush tty buffer and allow ldisc to process ioctl */ 292986c80a8eSPeter Hurley tty_buffer_flush(tty, NULL); 293096fd7ce5SGreg Kroah-Hartman break; 293196fd7ce5SGreg Kroah-Hartman } 293296fd7ce5SGreg Kroah-Hartman break; 29338a8ae62fSJiri Slaby case TIOCSSERIAL: 29348a8ae62fSJiri Slaby tty_warn_deprecated_flags(p); 29358a8ae62fSJiri Slaby break; 293696fd7ce5SGreg Kroah-Hartman } 293796fd7ce5SGreg Kroah-Hartman if (tty->ops->ioctl) { 2938c961bfb1SPeter Hurley retval = tty->ops->ioctl(tty, cmd, arg); 293996fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 294096fd7ce5SGreg Kroah-Hartman return retval; 294196fd7ce5SGreg Kroah-Hartman } 294296fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 294396fd7ce5SGreg Kroah-Hartman retval = -EINVAL; 294496fd7ce5SGreg Kroah-Hartman if (ld->ops->ioctl) { 294596fd7ce5SGreg Kroah-Hartman retval = ld->ops->ioctl(tty, file, cmd, arg); 294696fd7ce5SGreg Kroah-Hartman if (retval == -ENOIOCTLCMD) 2947bbb63c51SWanlong Gao retval = -ENOTTY; 294896fd7ce5SGreg Kroah-Hartman } 294996fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 295096fd7ce5SGreg Kroah-Hartman return retval; 295196fd7ce5SGreg Kroah-Hartman } 295296fd7ce5SGreg Kroah-Hartman 295396fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 295496fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 295596fd7ce5SGreg Kroah-Hartman unsigned long arg) 295696fd7ce5SGreg Kroah-Hartman { 295796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 295896fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 295996fd7ce5SGreg Kroah-Hartman int retval = -ENOIOCTLCMD; 296096fd7ce5SGreg Kroah-Hartman 29616131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 296296fd7ce5SGreg Kroah-Hartman return -EINVAL; 296396fd7ce5SGreg Kroah-Hartman 296496fd7ce5SGreg Kroah-Hartman if (tty->ops->compat_ioctl) { 2965c961bfb1SPeter Hurley retval = tty->ops->compat_ioctl(tty, cmd, arg); 296696fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 296796fd7ce5SGreg Kroah-Hartman return retval; 296896fd7ce5SGreg Kroah-Hartman } 296996fd7ce5SGreg Kroah-Hartman 297096fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 297196fd7ce5SGreg Kroah-Hartman if (ld->ops->compat_ioctl) 297296fd7ce5SGreg Kroah-Hartman retval = ld->ops->compat_ioctl(tty, file, cmd, arg); 29738193c429SThomas Meyer else 29748193c429SThomas Meyer retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg); 297596fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 297696fd7ce5SGreg Kroah-Hartman 297796fd7ce5SGreg Kroah-Hartman return retval; 297896fd7ce5SGreg Kroah-Hartman } 297996fd7ce5SGreg Kroah-Hartman #endif 298096fd7ce5SGreg Kroah-Hartman 2981c3c073f8SAl Viro static int this_tty(const void *t, struct file *file, unsigned fd) 2982c3c073f8SAl Viro { 2983c3c073f8SAl Viro if (likely(file->f_op->read != tty_read)) 2984c3c073f8SAl Viro return 0; 2985c3c073f8SAl Viro return file_tty(file) != t ? 0 : fd + 1; 2986c3c073f8SAl Viro } 2987c3c073f8SAl Viro 298896fd7ce5SGreg Kroah-Hartman /* 298996fd7ce5SGreg Kroah-Hartman * This implements the "Secure Attention Key" --- the idea is to 299096fd7ce5SGreg Kroah-Hartman * prevent trojan horses by killing all processes associated with this 299196fd7ce5SGreg Kroah-Hartman * tty when the user hits the "Secure Attention Key". Required for 299296fd7ce5SGreg Kroah-Hartman * super-paranoid applications --- see the Orange Book for more details. 299396fd7ce5SGreg Kroah-Hartman * 299496fd7ce5SGreg Kroah-Hartman * This code could be nicer; ideally it should send a HUP, wait a few 299596fd7ce5SGreg Kroah-Hartman * seconds, then send a INT, and then a KILL signal. But you then 299696fd7ce5SGreg Kroah-Hartman * have to coordinate with the init process, since all processes associated 299796fd7ce5SGreg Kroah-Hartman * with the current tty must be dead before the new getty is allowed 299896fd7ce5SGreg Kroah-Hartman * to spawn. 299996fd7ce5SGreg Kroah-Hartman * 300096fd7ce5SGreg Kroah-Hartman * Now, if it would be correct ;-/ The current code has a nasty hole - 300196fd7ce5SGreg Kroah-Hartman * it doesn't catch files in flight. We may send the descriptor to ourselves 300296fd7ce5SGreg Kroah-Hartman * via AF_UNIX socket, close it and later fetch from socket. FIXME. 300396fd7ce5SGreg Kroah-Hartman * 300496fd7ce5SGreg Kroah-Hartman * Nasty bug: do_SAK is being called in interrupt context. This can 300596fd7ce5SGreg Kroah-Hartman * deadlock. We punt it up to process context. AKPM - 16Mar2001 300696fd7ce5SGreg Kroah-Hartman */ 300796fd7ce5SGreg Kroah-Hartman void __do_SAK(struct tty_struct *tty) 300896fd7ce5SGreg Kroah-Hartman { 300996fd7ce5SGreg Kroah-Hartman #ifdef TTY_SOFT_SAK 301096fd7ce5SGreg Kroah-Hartman tty_hangup(tty); 301196fd7ce5SGreg Kroah-Hartman #else 301296fd7ce5SGreg Kroah-Hartman struct task_struct *g, *p; 301396fd7ce5SGreg Kroah-Hartman struct pid *session; 301496fd7ce5SGreg Kroah-Hartman int i; 301596fd7ce5SGreg Kroah-Hartman 301696fd7ce5SGreg Kroah-Hartman if (!tty) 301796fd7ce5SGreg Kroah-Hartman return; 301896fd7ce5SGreg Kroah-Hartman session = tty->session; 301996fd7ce5SGreg Kroah-Hartman 302096fd7ce5SGreg Kroah-Hartman tty_ldisc_flush(tty); 302196fd7ce5SGreg Kroah-Hartman 302296fd7ce5SGreg Kroah-Hartman tty_driver_flush_buffer(tty); 302396fd7ce5SGreg Kroah-Hartman 302496fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 302596fd7ce5SGreg Kroah-Hartman /* Kill the entire session */ 302696fd7ce5SGreg Kroah-Hartman do_each_pid_task(session, PIDTYPE_SID, p) { 30279b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by session\n", 302896fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 302996fd7ce5SGreg Kroah-Hartman send_sig(SIGKILL, p, 1); 303096fd7ce5SGreg Kroah-Hartman } while_each_pid_task(session, PIDTYPE_SID, p); 30319b42bb75SPeter Hurley 30329b42bb75SPeter Hurley /* Now kill any processes that happen to have the tty open */ 303396fd7ce5SGreg Kroah-Hartman do_each_thread(g, p) { 303496fd7ce5SGreg Kroah-Hartman if (p->signal->tty == tty) { 30359b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by controlling tty\n", 303696fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 303796fd7ce5SGreg Kroah-Hartman send_sig(SIGKILL, p, 1); 303896fd7ce5SGreg Kroah-Hartman continue; 303996fd7ce5SGreg Kroah-Hartman } 304096fd7ce5SGreg Kroah-Hartman task_lock(p); 3041c3c073f8SAl Viro i = iterate_fd(p->files, 0, this_tty, tty); 3042c3c073f8SAl Viro if (i != 0) { 30439b42bb75SPeter Hurley tty_notice(tty, "SAK: killed process %d (%s): by fd#%d\n", 3044c3c073f8SAl Viro task_pid_nr(p), p->comm, i - 1); 304596fd7ce5SGreg Kroah-Hartman force_sig(SIGKILL, p); 304696fd7ce5SGreg Kroah-Hartman } 304796fd7ce5SGreg Kroah-Hartman task_unlock(p); 304896fd7ce5SGreg Kroah-Hartman } while_each_thread(g, p); 304996fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 305096fd7ce5SGreg Kroah-Hartman #endif 305196fd7ce5SGreg Kroah-Hartman } 305296fd7ce5SGreg Kroah-Hartman 305396fd7ce5SGreg Kroah-Hartman static void do_SAK_work(struct work_struct *work) 305496fd7ce5SGreg Kroah-Hartman { 305596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 305696fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, SAK_work); 305796fd7ce5SGreg Kroah-Hartman __do_SAK(tty); 305896fd7ce5SGreg Kroah-Hartman } 305996fd7ce5SGreg Kroah-Hartman 306096fd7ce5SGreg Kroah-Hartman /* 306196fd7ce5SGreg Kroah-Hartman * The tq handling here is a little racy - tty->SAK_work may already be queued. 306296fd7ce5SGreg Kroah-Hartman * Fortunately we don't need to worry, because if ->SAK_work is already queued, 306396fd7ce5SGreg Kroah-Hartman * the values which we write to it will be identical to the values which it 306496fd7ce5SGreg Kroah-Hartman * already has. --akpm 306596fd7ce5SGreg Kroah-Hartman */ 306696fd7ce5SGreg Kroah-Hartman void do_SAK(struct tty_struct *tty) 306796fd7ce5SGreg Kroah-Hartman { 306896fd7ce5SGreg Kroah-Hartman if (!tty) 306996fd7ce5SGreg Kroah-Hartman return; 307096fd7ce5SGreg Kroah-Hartman schedule_work(&tty->SAK_work); 307196fd7ce5SGreg Kroah-Hartman } 307296fd7ce5SGreg Kroah-Hartman 307396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(do_SAK); 307496fd7ce5SGreg Kroah-Hartman 30756e9430acSGreg Kroah-Hartman static int dev_match_devt(struct device *dev, const void *data) 307696fd7ce5SGreg Kroah-Hartman { 30776e9430acSGreg Kroah-Hartman const dev_t *devt = data; 307896fd7ce5SGreg Kroah-Hartman return dev->devt == *devt; 307996fd7ce5SGreg Kroah-Hartman } 308096fd7ce5SGreg Kroah-Hartman 308196fd7ce5SGreg Kroah-Hartman /* Must put_device() after it's unused! */ 308296fd7ce5SGreg Kroah-Hartman static struct device *tty_get_device(struct tty_struct *tty) 308396fd7ce5SGreg Kroah-Hartman { 308496fd7ce5SGreg Kroah-Hartman dev_t devt = tty_devnum(tty); 308596fd7ce5SGreg Kroah-Hartman return class_find_device(tty_class, NULL, &devt, dev_match_devt); 308696fd7ce5SGreg Kroah-Hartman } 308796fd7ce5SGreg Kroah-Hartman 308896fd7ce5SGreg Kroah-Hartman 308996fd7ce5SGreg Kroah-Hartman /** 30902c964a2fSRasmus Villemoes * alloc_tty_struct 309196fd7ce5SGreg Kroah-Hartman * 30922c964a2fSRasmus Villemoes * This subroutine allocates and initializes a tty structure. 309396fd7ce5SGreg Kroah-Hartman * 30942c964a2fSRasmus Villemoes * Locking: none - tty in question is not exposed at this point 309596fd7ce5SGreg Kroah-Hartman */ 309696fd7ce5SGreg Kroah-Hartman 30972c964a2fSRasmus Villemoes struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx) 309896fd7ce5SGreg Kroah-Hartman { 30992c964a2fSRasmus Villemoes struct tty_struct *tty; 31002c964a2fSRasmus Villemoes 31012c964a2fSRasmus Villemoes tty = kzalloc(sizeof(*tty), GFP_KERNEL); 31022c964a2fSRasmus Villemoes if (!tty) 31032c964a2fSRasmus Villemoes return NULL; 31042c964a2fSRasmus Villemoes 310596fd7ce5SGreg Kroah-Hartman kref_init(&tty->kref); 310696fd7ce5SGreg Kroah-Hartman tty->magic = TTY_MAGIC; 310796fd7ce5SGreg Kroah-Hartman tty_ldisc_init(tty); 310896fd7ce5SGreg Kroah-Hartman tty->session = NULL; 310996fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 311089c8d91eSAlan Cox mutex_init(&tty->legacy_mutex); 3111d8c1f929SPeter Hurley mutex_init(&tty->throttle_mutex); 31126a1c0680SPeter Hurley init_rwsem(&tty->termios_rwsem); 3113dee4a0beSPeter Hurley mutex_init(&tty->winsize_mutex); 311436697529SPeter Hurley init_ldsem(&tty->ldisc_sem); 311596fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->write_wait); 311696fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->read_wait); 311796fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, do_tty_hangup); 311896fd7ce5SGreg Kroah-Hartman mutex_init(&tty->atomic_write_lock); 311996fd7ce5SGreg Kroah-Hartman spin_lock_init(&tty->ctrl_lock); 3120f9e053dcSPeter Hurley spin_lock_init(&tty->flow_lock); 312196fd7ce5SGreg Kroah-Hartman INIT_LIST_HEAD(&tty->tty_files); 312296fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->SAK_work, do_SAK_work); 312396fd7ce5SGreg Kroah-Hartman 312496fd7ce5SGreg Kroah-Hartman tty->driver = driver; 312596fd7ce5SGreg Kroah-Hartman tty->ops = driver->ops; 312696fd7ce5SGreg Kroah-Hartman tty->index = idx; 312796fd7ce5SGreg Kroah-Hartman tty_line_name(driver, idx, tty->name); 312896fd7ce5SGreg Kroah-Hartman tty->dev = tty_get_device(tty); 31292c964a2fSRasmus Villemoes 31302c964a2fSRasmus Villemoes return tty; 313196fd7ce5SGreg Kroah-Hartman } 313296fd7ce5SGreg Kroah-Hartman 313396fd7ce5SGreg Kroah-Hartman /** 31346716671dSJiri Slaby * deinitialize_tty_struct 31356716671dSJiri Slaby * @tty: tty to deinitialize 31366716671dSJiri Slaby * 31376716671dSJiri Slaby * This subroutine deinitializes a tty structure that has been newly 31386716671dSJiri Slaby * allocated but tty_release cannot be called on that yet. 31396716671dSJiri Slaby * 31406716671dSJiri Slaby * Locking: none - tty in question must not be exposed at this point 31416716671dSJiri Slaby */ 31426716671dSJiri Slaby void deinitialize_tty_struct(struct tty_struct *tty) 31436716671dSJiri Slaby { 31446716671dSJiri Slaby tty_ldisc_deinit(tty); 31456716671dSJiri Slaby } 31466716671dSJiri Slaby 31476716671dSJiri Slaby /** 314896fd7ce5SGreg Kroah-Hartman * tty_put_char - write one character to a tty 314996fd7ce5SGreg Kroah-Hartman * @tty: tty 315096fd7ce5SGreg Kroah-Hartman * @ch: character 315196fd7ce5SGreg Kroah-Hartman * 315296fd7ce5SGreg Kroah-Hartman * Write one byte to the tty using the provided put_char method 315396fd7ce5SGreg Kroah-Hartman * if present. Returns the number of characters successfully output. 315496fd7ce5SGreg Kroah-Hartman * 315596fd7ce5SGreg Kroah-Hartman * Note: the specific put_char operation in the driver layer may go 315696fd7ce5SGreg Kroah-Hartman * away soon. Don't call it directly, use this method 315796fd7ce5SGreg Kroah-Hartman */ 315896fd7ce5SGreg Kroah-Hartman 315996fd7ce5SGreg Kroah-Hartman int tty_put_char(struct tty_struct *tty, unsigned char ch) 316096fd7ce5SGreg Kroah-Hartman { 316196fd7ce5SGreg Kroah-Hartman if (tty->ops->put_char) 316296fd7ce5SGreg Kroah-Hartman return tty->ops->put_char(tty, ch); 316396fd7ce5SGreg Kroah-Hartman return tty->ops->write(tty, &ch, 1); 316496fd7ce5SGreg Kroah-Hartman } 316596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_put_char); 316696fd7ce5SGreg Kroah-Hartman 316796fd7ce5SGreg Kroah-Hartman struct class *tty_class; 316896fd7ce5SGreg Kroah-Hartman 31697e73eca6SJiri Slaby static int tty_cdev_add(struct tty_driver *driver, dev_t dev, 31707e73eca6SJiri Slaby unsigned int index, unsigned int count) 31717e73eca6SJiri Slaby { 3172c1a752baSLeon Yu int err; 3173c1a752baSLeon Yu 31747e73eca6SJiri Slaby /* init here, since reused cdevs cause crashes */ 3175a3a10ce3SRichard Watts driver->cdevs[index] = cdev_alloc(); 3176a3a10ce3SRichard Watts if (!driver->cdevs[index]) 3177a3a10ce3SRichard Watts return -ENOMEM; 3178c1a752baSLeon Yu driver->cdevs[index]->ops = &tty_fops; 3179a3a10ce3SRichard Watts driver->cdevs[index]->owner = driver->owner; 3180c1a752baSLeon Yu err = cdev_add(driver->cdevs[index], dev, count); 3181c1a752baSLeon Yu if (err) 3182c1a752baSLeon Yu kobject_put(&driver->cdevs[index]->kobj); 3183c1a752baSLeon Yu return err; 31847e73eca6SJiri Slaby } 31857e73eca6SJiri Slaby 318696fd7ce5SGreg Kroah-Hartman /** 318796fd7ce5SGreg Kroah-Hartman * tty_register_device - register a tty device 318896fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 318996fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 319096fd7ce5SGreg Kroah-Hartman * @device: a struct device that is associated with this tty device. 319196fd7ce5SGreg Kroah-Hartman * This field is optional, if there is no known struct device 319296fd7ce5SGreg Kroah-Hartman * for this tty device it can be set to NULL safely. 319396fd7ce5SGreg Kroah-Hartman * 319496fd7ce5SGreg Kroah-Hartman * Returns a pointer to the struct device for this tty device 319596fd7ce5SGreg Kroah-Hartman * (or ERR_PTR(-EFOO) on error). 319696fd7ce5SGreg Kroah-Hartman * 319796fd7ce5SGreg Kroah-Hartman * This call is required to be made to register an individual tty device 319896fd7ce5SGreg Kroah-Hartman * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 319996fd7ce5SGreg Kroah-Hartman * that bit is not set, this function should not be called by a tty 320096fd7ce5SGreg Kroah-Hartman * driver. 320196fd7ce5SGreg Kroah-Hartman * 320296fd7ce5SGreg Kroah-Hartman * Locking: ?? 320396fd7ce5SGreg Kroah-Hartman */ 320496fd7ce5SGreg Kroah-Hartman 320596fd7ce5SGreg Kroah-Hartman struct device *tty_register_device(struct tty_driver *driver, unsigned index, 320696fd7ce5SGreg Kroah-Hartman struct device *device) 320796fd7ce5SGreg Kroah-Hartman { 32086915c0e4STomas Hlavacek return tty_register_device_attr(driver, index, device, NULL, NULL); 32096915c0e4STomas Hlavacek } 32106915c0e4STomas Hlavacek EXPORT_SYMBOL(tty_register_device); 32116915c0e4STomas Hlavacek 3212b1b79916STomas Hlavacek static void tty_device_create_release(struct device *dev) 3213b1b79916STomas Hlavacek { 321483db1df4SPeter Hurley dev_dbg(dev, "releasing...\n"); 3215b1b79916STomas Hlavacek kfree(dev); 3216b1b79916STomas Hlavacek } 3217b1b79916STomas Hlavacek 32186915c0e4STomas Hlavacek /** 32196915c0e4STomas Hlavacek * tty_register_device_attr - register a tty device 32206915c0e4STomas Hlavacek * @driver: the tty driver that describes the tty device 32216915c0e4STomas Hlavacek * @index: the index in the tty driver for this tty device 32226915c0e4STomas Hlavacek * @device: a struct device that is associated with this tty device. 32236915c0e4STomas Hlavacek * This field is optional, if there is no known struct device 32246915c0e4STomas Hlavacek * for this tty device it can be set to NULL safely. 32256915c0e4STomas Hlavacek * @drvdata: Driver data to be set to device. 32266915c0e4STomas Hlavacek * @attr_grp: Attribute group to be set on device. 32276915c0e4STomas Hlavacek * 32286915c0e4STomas Hlavacek * Returns a pointer to the struct device for this tty device 32296915c0e4STomas Hlavacek * (or ERR_PTR(-EFOO) on error). 32306915c0e4STomas Hlavacek * 32316915c0e4STomas Hlavacek * This call is required to be made to register an individual tty device 32326915c0e4STomas Hlavacek * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 32336915c0e4STomas Hlavacek * that bit is not set, this function should not be called by a tty 32346915c0e4STomas Hlavacek * driver. 32356915c0e4STomas Hlavacek * 32366915c0e4STomas Hlavacek * Locking: ?? 32376915c0e4STomas Hlavacek */ 32386915c0e4STomas Hlavacek struct device *tty_register_device_attr(struct tty_driver *driver, 32396915c0e4STomas Hlavacek unsigned index, struct device *device, 32406915c0e4STomas Hlavacek void *drvdata, 32416915c0e4STomas Hlavacek const struct attribute_group **attr_grp) 32426915c0e4STomas Hlavacek { 324396fd7ce5SGreg Kroah-Hartman char name[64]; 32446915c0e4STomas Hlavacek dev_t devt = MKDEV(driver->major, driver->minor_start) + index; 32456915c0e4STomas Hlavacek struct device *dev = NULL; 32466915c0e4STomas Hlavacek int retval = -ENODEV; 32477e73eca6SJiri Slaby bool cdev = false; 324896fd7ce5SGreg Kroah-Hartman 324996fd7ce5SGreg Kroah-Hartman if (index >= driver->num) { 3250656fb867SPeter Hurley pr_err("%s: Attempt to register invalid tty line number (%d)\n", 3251656fb867SPeter Hurley driver->name, index); 325296fd7ce5SGreg Kroah-Hartman return ERR_PTR(-EINVAL); 325396fd7ce5SGreg Kroah-Hartman } 325496fd7ce5SGreg Kroah-Hartman 325596fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY) 325696fd7ce5SGreg Kroah-Hartman pty_line_name(driver, index, name); 325796fd7ce5SGreg Kroah-Hartman else 325896fd7ce5SGreg Kroah-Hartman tty_line_name(driver, index, name); 325996fd7ce5SGreg Kroah-Hartman 32607e73eca6SJiri Slaby if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 32616915c0e4STomas Hlavacek retval = tty_cdev_add(driver, devt, index, 1); 32626915c0e4STomas Hlavacek if (retval) 32636915c0e4STomas Hlavacek goto error; 32647e73eca6SJiri Slaby cdev = true; 32657e73eca6SJiri Slaby } 32667e73eca6SJiri Slaby 32676915c0e4STomas Hlavacek dev = kzalloc(sizeof(*dev), GFP_KERNEL); 32686915c0e4STomas Hlavacek if (!dev) { 32696915c0e4STomas Hlavacek retval = -ENOMEM; 32706915c0e4STomas Hlavacek goto error; 327196fd7ce5SGreg Kroah-Hartman } 32726915c0e4STomas Hlavacek 32736915c0e4STomas Hlavacek dev->devt = devt; 32746915c0e4STomas Hlavacek dev->class = tty_class; 32756915c0e4STomas Hlavacek dev->parent = device; 3276b1b79916STomas Hlavacek dev->release = tty_device_create_release; 32776915c0e4STomas Hlavacek dev_set_name(dev, "%s", name); 32786915c0e4STomas Hlavacek dev->groups = attr_grp; 32796915c0e4STomas Hlavacek dev_set_drvdata(dev, drvdata); 32806915c0e4STomas Hlavacek 32816915c0e4STomas Hlavacek retval = device_register(dev); 32826915c0e4STomas Hlavacek if (retval) 32836915c0e4STomas Hlavacek goto error; 32846915c0e4STomas Hlavacek 32856915c0e4STomas Hlavacek return dev; 32866915c0e4STomas Hlavacek 32876915c0e4STomas Hlavacek error: 32886915c0e4STomas Hlavacek put_device(dev); 3289a3a10ce3SRichard Watts if (cdev) { 3290a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3291a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3292a3a10ce3SRichard Watts } 32936915c0e4STomas Hlavacek return ERR_PTR(retval); 32946915c0e4STomas Hlavacek } 32956915c0e4STomas Hlavacek EXPORT_SYMBOL_GPL(tty_register_device_attr); 329696fd7ce5SGreg Kroah-Hartman 329796fd7ce5SGreg Kroah-Hartman /** 329896fd7ce5SGreg Kroah-Hartman * tty_unregister_device - unregister a tty device 329996fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 330096fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 330196fd7ce5SGreg Kroah-Hartman * 330296fd7ce5SGreg Kroah-Hartman * If a tty device is registered with a call to tty_register_device() then 330396fd7ce5SGreg Kroah-Hartman * this function must be called when the tty device is gone. 330496fd7ce5SGreg Kroah-Hartman * 330596fd7ce5SGreg Kroah-Hartman * Locking: ?? 330696fd7ce5SGreg Kroah-Hartman */ 330796fd7ce5SGreg Kroah-Hartman 330896fd7ce5SGreg Kroah-Hartman void tty_unregister_device(struct tty_driver *driver, unsigned index) 330996fd7ce5SGreg Kroah-Hartman { 331096fd7ce5SGreg Kroah-Hartman device_destroy(tty_class, 331196fd7ce5SGreg Kroah-Hartman MKDEV(driver->major, driver->minor_start) + index); 3312a3a10ce3SRichard Watts if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 3313a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3314a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3315a3a10ce3SRichard Watts } 331696fd7ce5SGreg Kroah-Hartman } 331796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_device); 331896fd7ce5SGreg Kroah-Hartman 33197f0bc6a6SJiri Slaby /** 33207f0bc6a6SJiri Slaby * __tty_alloc_driver -- allocate tty driver 33217f0bc6a6SJiri Slaby * @lines: count of lines this driver can handle at most 33227f0bc6a6SJiri Slaby * @owner: module which is repsonsible for this driver 33237f0bc6a6SJiri Slaby * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags 33247f0bc6a6SJiri Slaby * 33257f0bc6a6SJiri Slaby * This should not be called directly, some of the provided macros should be 33267f0bc6a6SJiri Slaby * used instead. Use IS_ERR and friends on @retval. 33277f0bc6a6SJiri Slaby */ 33287f0bc6a6SJiri Slaby struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner, 33297f0bc6a6SJiri Slaby unsigned long flags) 333096fd7ce5SGreg Kroah-Hartman { 333196fd7ce5SGreg Kroah-Hartman struct tty_driver *driver; 33327e73eca6SJiri Slaby unsigned int cdevs = 1; 333316a02081SJiri Slaby int err; 333496fd7ce5SGreg Kroah-Hartman 33350019b408SJiri Slaby if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1)) 33367f0bc6a6SJiri Slaby return ERR_PTR(-EINVAL); 33377f0bc6a6SJiri Slaby 333896fd7ce5SGreg Kroah-Hartman driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); 33397f0bc6a6SJiri Slaby if (!driver) 33407f0bc6a6SJiri Slaby return ERR_PTR(-ENOMEM); 33417f0bc6a6SJiri Slaby 334296fd7ce5SGreg Kroah-Hartman kref_init(&driver->kref); 334396fd7ce5SGreg Kroah-Hartman driver->magic = TTY_DRIVER_MAGIC; 334496fd7ce5SGreg Kroah-Hartman driver->num = lines; 33451a54a76dSJiri Slaby driver->owner = owner; 33467f0bc6a6SJiri Slaby driver->flags = flags; 334716a02081SJiri Slaby 334816a02081SJiri Slaby if (!(flags & TTY_DRIVER_DEVPTS_MEM)) { 334916a02081SJiri Slaby driver->ttys = kcalloc(lines, sizeof(*driver->ttys), 335016a02081SJiri Slaby GFP_KERNEL); 335116a02081SJiri Slaby driver->termios = kcalloc(lines, sizeof(*driver->termios), 335216a02081SJiri Slaby GFP_KERNEL); 335316a02081SJiri Slaby if (!driver->ttys || !driver->termios) { 335416a02081SJiri Slaby err = -ENOMEM; 335516a02081SJiri Slaby goto err_free_all; 335616a02081SJiri Slaby } 335716a02081SJiri Slaby } 335816a02081SJiri Slaby 335916a02081SJiri Slaby if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 336016a02081SJiri Slaby driver->ports = kcalloc(lines, sizeof(*driver->ports), 336116a02081SJiri Slaby GFP_KERNEL); 336216a02081SJiri Slaby if (!driver->ports) { 336316a02081SJiri Slaby err = -ENOMEM; 336416a02081SJiri Slaby goto err_free_all; 336516a02081SJiri Slaby } 33667e73eca6SJiri Slaby cdevs = lines; 33677e73eca6SJiri Slaby } 33687e73eca6SJiri Slaby 33697e73eca6SJiri Slaby driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL); 33707e73eca6SJiri Slaby if (!driver->cdevs) { 33717e73eca6SJiri Slaby err = -ENOMEM; 33727e73eca6SJiri Slaby goto err_free_all; 337316a02081SJiri Slaby } 33747f0bc6a6SJiri Slaby 337596fd7ce5SGreg Kroah-Hartman return driver; 337616a02081SJiri Slaby err_free_all: 337716a02081SJiri Slaby kfree(driver->ports); 337816a02081SJiri Slaby kfree(driver->ttys); 337916a02081SJiri Slaby kfree(driver->termios); 3380a3a10ce3SRichard Watts kfree(driver->cdevs); 338116a02081SJiri Slaby kfree(driver); 338216a02081SJiri Slaby return ERR_PTR(err); 338396fd7ce5SGreg Kroah-Hartman } 33847f0bc6a6SJiri Slaby EXPORT_SYMBOL(__tty_alloc_driver); 338596fd7ce5SGreg Kroah-Hartman 338696fd7ce5SGreg Kroah-Hartman static void destruct_tty_driver(struct kref *kref) 338796fd7ce5SGreg Kroah-Hartman { 338896fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = container_of(kref, struct tty_driver, kref); 338996fd7ce5SGreg Kroah-Hartman int i; 339096fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 339196fd7ce5SGreg Kroah-Hartman 339296fd7ce5SGreg Kroah-Hartman if (driver->flags & TTY_DRIVER_INSTALLED) { 339396fd7ce5SGreg Kroah-Hartman /* 339496fd7ce5SGreg Kroah-Hartman * Free the termios and termios_locked structures because 339596fd7ce5SGreg Kroah-Hartman * we don't want to get memory leaks when modular tty 339696fd7ce5SGreg Kroah-Hartman * drivers are removed from the kernel. 339796fd7ce5SGreg Kroah-Hartman */ 339896fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 339996fd7ce5SGreg Kroah-Hartman tp = driver->termios[i]; 340096fd7ce5SGreg Kroah-Hartman if (tp) { 340196fd7ce5SGreg Kroah-Hartman driver->termios[i] = NULL; 340296fd7ce5SGreg Kroah-Hartman kfree(tp); 340396fd7ce5SGreg Kroah-Hartman } 340496fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) 340596fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 340696fd7ce5SGreg Kroah-Hartman } 340796fd7ce5SGreg Kroah-Hartman proc_tty_unregister_driver(driver); 34087e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) 3409a3a10ce3SRichard Watts cdev_del(driver->cdevs[0]); 341096fd7ce5SGreg Kroah-Hartman } 34117e73eca6SJiri Slaby kfree(driver->cdevs); 341204831dc1SJiri Slaby kfree(driver->ports); 341316a02081SJiri Slaby kfree(driver->termios); 341416a02081SJiri Slaby kfree(driver->ttys); 341596fd7ce5SGreg Kroah-Hartman kfree(driver); 341696fd7ce5SGreg Kroah-Hartman } 341796fd7ce5SGreg Kroah-Hartman 341896fd7ce5SGreg Kroah-Hartman void tty_driver_kref_put(struct tty_driver *driver) 341996fd7ce5SGreg Kroah-Hartman { 342096fd7ce5SGreg Kroah-Hartman kref_put(&driver->kref, destruct_tty_driver); 342196fd7ce5SGreg Kroah-Hartman } 342296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_driver_kref_put); 342396fd7ce5SGreg Kroah-Hartman 342496fd7ce5SGreg Kroah-Hartman void tty_set_operations(struct tty_driver *driver, 342596fd7ce5SGreg Kroah-Hartman const struct tty_operations *op) 342696fd7ce5SGreg Kroah-Hartman { 342796fd7ce5SGreg Kroah-Hartman driver->ops = op; 342896fd7ce5SGreg Kroah-Hartman }; 342996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_set_operations); 343096fd7ce5SGreg Kroah-Hartman 343196fd7ce5SGreg Kroah-Hartman void put_tty_driver(struct tty_driver *d) 343296fd7ce5SGreg Kroah-Hartman { 343396fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(d); 343496fd7ce5SGreg Kroah-Hartman } 343596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(put_tty_driver); 343696fd7ce5SGreg Kroah-Hartman 343796fd7ce5SGreg Kroah-Hartman /* 343896fd7ce5SGreg Kroah-Hartman * Called by a tty driver to register itself. 343996fd7ce5SGreg Kroah-Hartman */ 344096fd7ce5SGreg Kroah-Hartman int tty_register_driver(struct tty_driver *driver) 344196fd7ce5SGreg Kroah-Hartman { 344296fd7ce5SGreg Kroah-Hartman int error; 344396fd7ce5SGreg Kroah-Hartman int i; 344496fd7ce5SGreg Kroah-Hartman dev_t dev; 344596fd7ce5SGreg Kroah-Hartman struct device *d; 344696fd7ce5SGreg Kroah-Hartman 344796fd7ce5SGreg Kroah-Hartman if (!driver->major) { 344896fd7ce5SGreg Kroah-Hartman error = alloc_chrdev_region(&dev, driver->minor_start, 344996fd7ce5SGreg Kroah-Hartman driver->num, driver->name); 345096fd7ce5SGreg Kroah-Hartman if (!error) { 345196fd7ce5SGreg Kroah-Hartman driver->major = MAJOR(dev); 345296fd7ce5SGreg Kroah-Hartman driver->minor_start = MINOR(dev); 345396fd7ce5SGreg Kroah-Hartman } 345496fd7ce5SGreg Kroah-Hartman } else { 345596fd7ce5SGreg Kroah-Hartman dev = MKDEV(driver->major, driver->minor_start); 345696fd7ce5SGreg Kroah-Hartman error = register_chrdev_region(dev, driver->num, driver->name); 345796fd7ce5SGreg Kroah-Hartman } 34589bb8a3d4SJiri Slaby if (error < 0) 345916a02081SJiri Slaby goto err; 346096fd7ce5SGreg Kroah-Hartman 34617e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) { 34627e73eca6SJiri Slaby error = tty_cdev_add(driver, dev, 0, driver->num); 34639bb8a3d4SJiri Slaby if (error) 34649bb8a3d4SJiri Slaby goto err_unreg_char; 34657e73eca6SJiri Slaby } 346696fd7ce5SGreg Kroah-Hartman 346796fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 346896fd7ce5SGreg Kroah-Hartman list_add(&driver->tty_drivers, &tty_drivers); 346996fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 347096fd7ce5SGreg Kroah-Hartman 347196fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { 347296fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 347396fd7ce5SGreg Kroah-Hartman d = tty_register_device(driver, i, NULL); 347496fd7ce5SGreg Kroah-Hartman if (IS_ERR(d)) { 347596fd7ce5SGreg Kroah-Hartman error = PTR_ERR(d); 347616a02081SJiri Slaby goto err_unreg_devs; 347796fd7ce5SGreg Kroah-Hartman } 347896fd7ce5SGreg Kroah-Hartman } 347996fd7ce5SGreg Kroah-Hartman } 348096fd7ce5SGreg Kroah-Hartman proc_tty_register_driver(driver); 348196fd7ce5SGreg Kroah-Hartman driver->flags |= TTY_DRIVER_INSTALLED; 348296fd7ce5SGreg Kroah-Hartman return 0; 348396fd7ce5SGreg Kroah-Hartman 348416a02081SJiri Slaby err_unreg_devs: 348596fd7ce5SGreg Kroah-Hartman for (i--; i >= 0; i--) 348696fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 348796fd7ce5SGreg Kroah-Hartman 348896fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 348996fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 349096fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 349196fd7ce5SGreg Kroah-Hartman 34929bb8a3d4SJiri Slaby err_unreg_char: 349396fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(dev, driver->num); 349416a02081SJiri Slaby err: 349596fd7ce5SGreg Kroah-Hartman return error; 349696fd7ce5SGreg Kroah-Hartman } 349796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_register_driver); 349896fd7ce5SGreg Kroah-Hartman 349996fd7ce5SGreg Kroah-Hartman /* 350096fd7ce5SGreg Kroah-Hartman * Called by a tty driver to unregister itself. 350196fd7ce5SGreg Kroah-Hartman */ 350296fd7ce5SGreg Kroah-Hartman int tty_unregister_driver(struct tty_driver *driver) 350396fd7ce5SGreg Kroah-Hartman { 350496fd7ce5SGreg Kroah-Hartman #if 0 350596fd7ce5SGreg Kroah-Hartman /* FIXME */ 350696fd7ce5SGreg Kroah-Hartman if (driver->refcount) 350796fd7ce5SGreg Kroah-Hartman return -EBUSY; 350896fd7ce5SGreg Kroah-Hartman #endif 350996fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), 351096fd7ce5SGreg Kroah-Hartman driver->num); 351196fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 351296fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 351396fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 351496fd7ce5SGreg Kroah-Hartman return 0; 351596fd7ce5SGreg Kroah-Hartman } 351696fd7ce5SGreg Kroah-Hartman 351796fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_driver); 351896fd7ce5SGreg Kroah-Hartman 351996fd7ce5SGreg Kroah-Hartman dev_t tty_devnum(struct tty_struct *tty) 352096fd7ce5SGreg Kroah-Hartman { 352196fd7ce5SGreg Kroah-Hartman return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; 352296fd7ce5SGreg Kroah-Hartman } 352396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_devnum); 352496fd7ce5SGreg Kroah-Hartman 352596fd7ce5SGreg Kroah-Hartman void tty_default_fops(struct file_operations *fops) 352696fd7ce5SGreg Kroah-Hartman { 352796fd7ce5SGreg Kroah-Hartman *fops = tty_fops; 352896fd7ce5SGreg Kroah-Hartman } 352996fd7ce5SGreg Kroah-Hartman 353096fd7ce5SGreg Kroah-Hartman /* 353196fd7ce5SGreg Kroah-Hartman * Initialize the console device. This is called *early*, so 353296fd7ce5SGreg Kroah-Hartman * we can't necessarily depend on lots of kernel help here. 353396fd7ce5SGreg Kroah-Hartman * Just do some early initializations, and do the complex setup 353496fd7ce5SGreg Kroah-Hartman * later. 353596fd7ce5SGreg Kroah-Hartman */ 353696fd7ce5SGreg Kroah-Hartman void __init console_init(void) 353796fd7ce5SGreg Kroah-Hartman { 353896fd7ce5SGreg Kroah-Hartman initcall_t *call; 353996fd7ce5SGreg Kroah-Hartman 354096fd7ce5SGreg Kroah-Hartman /* Setup the default TTY line discipline. */ 354196fd7ce5SGreg Kroah-Hartman tty_ldisc_begin(); 354296fd7ce5SGreg Kroah-Hartman 354396fd7ce5SGreg Kroah-Hartman /* 354496fd7ce5SGreg Kroah-Hartman * set up the console device so that later boot sequences can 354596fd7ce5SGreg Kroah-Hartman * inform about problems etc.. 354696fd7ce5SGreg Kroah-Hartman */ 354796fd7ce5SGreg Kroah-Hartman call = __con_initcall_start; 354896fd7ce5SGreg Kroah-Hartman while (call < __con_initcall_end) { 354996fd7ce5SGreg Kroah-Hartman (*call)(); 355096fd7ce5SGreg Kroah-Hartman call++; 355196fd7ce5SGreg Kroah-Hartman } 355296fd7ce5SGreg Kroah-Hartman } 355396fd7ce5SGreg Kroah-Hartman 35542c9ede55SAl Viro static char *tty_devnode(struct device *dev, umode_t *mode) 355596fd7ce5SGreg Kroah-Hartman { 355696fd7ce5SGreg Kroah-Hartman if (!mode) 355796fd7ce5SGreg Kroah-Hartman return NULL; 355896fd7ce5SGreg Kroah-Hartman if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || 355996fd7ce5SGreg Kroah-Hartman dev->devt == MKDEV(TTYAUX_MAJOR, 2)) 356096fd7ce5SGreg Kroah-Hartman *mode = 0666; 356196fd7ce5SGreg Kroah-Hartman return NULL; 356296fd7ce5SGreg Kroah-Hartman } 356396fd7ce5SGreg Kroah-Hartman 356496fd7ce5SGreg Kroah-Hartman static int __init tty_class_init(void) 356596fd7ce5SGreg Kroah-Hartman { 356696fd7ce5SGreg Kroah-Hartman tty_class = class_create(THIS_MODULE, "tty"); 356796fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty_class)) 356896fd7ce5SGreg Kroah-Hartman return PTR_ERR(tty_class); 356996fd7ce5SGreg Kroah-Hartman tty_class->devnode = tty_devnode; 357096fd7ce5SGreg Kroah-Hartman return 0; 357196fd7ce5SGreg Kroah-Hartman } 357296fd7ce5SGreg Kroah-Hartman 357396fd7ce5SGreg Kroah-Hartman postcore_initcall(tty_class_init); 357496fd7ce5SGreg Kroah-Hartman 357596fd7ce5SGreg Kroah-Hartman /* 3/2004 jmc: why do these devices exist? */ 357696fd7ce5SGreg Kroah-Hartman static struct cdev tty_cdev, console_cdev; 357796fd7ce5SGreg Kroah-Hartman 3578fbc92a34SKay Sievers static ssize_t show_cons_active(struct device *dev, 3579fbc92a34SKay Sievers struct device_attribute *attr, char *buf) 3580fbc92a34SKay Sievers { 3581fbc92a34SKay Sievers struct console *cs[16]; 3582fbc92a34SKay Sievers int i = 0; 3583fbc92a34SKay Sievers struct console *c; 3584fbc92a34SKay Sievers ssize_t count = 0; 3585fbc92a34SKay Sievers 3586ac751efaSTorben Hohn console_lock(); 3587a2a6a822SKay Sievers for_each_console(c) { 3588fbc92a34SKay Sievers if (!c->device) 3589fbc92a34SKay Sievers continue; 3590fbc92a34SKay Sievers if (!c->write) 3591fbc92a34SKay Sievers continue; 3592fbc92a34SKay Sievers if ((c->flags & CON_ENABLED) == 0) 3593fbc92a34SKay Sievers continue; 3594fbc92a34SKay Sievers cs[i++] = c; 3595fbc92a34SKay Sievers if (i >= ARRAY_SIZE(cs)) 3596fbc92a34SKay Sievers break; 3597fbc92a34SKay Sievers } 3598723abd87SHannes Reinecke while (i--) { 3599723abd87SHannes Reinecke int index = cs[i]->index; 3600723abd87SHannes Reinecke struct tty_driver *drv = cs[i]->device(cs[i], &index); 3601723abd87SHannes Reinecke 3602723abd87SHannes Reinecke /* don't resolve tty0 as some programs depend on it */ 3603723abd87SHannes Reinecke if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR)) 3604723abd87SHannes Reinecke count += tty_line_name(drv, index, buf + count); 3605723abd87SHannes Reinecke else 3606723abd87SHannes Reinecke count += sprintf(buf + count, "%s%d", 3607723abd87SHannes Reinecke cs[i]->name, cs[i]->index); 3608723abd87SHannes Reinecke 3609723abd87SHannes Reinecke count += sprintf(buf + count, "%c", i ? ' ':'\n'); 3610723abd87SHannes Reinecke } 3611ac751efaSTorben Hohn console_unlock(); 3612fbc92a34SKay Sievers 3613fbc92a34SKay Sievers return count; 3614fbc92a34SKay Sievers } 3615fbc92a34SKay Sievers static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL); 3616fbc92a34SKay Sievers 36171083a7beSTakashi Iwai static struct attribute *cons_dev_attrs[] = { 36181083a7beSTakashi Iwai &dev_attr_active.attr, 36191083a7beSTakashi Iwai NULL 36201083a7beSTakashi Iwai }; 36211083a7beSTakashi Iwai 36221083a7beSTakashi Iwai ATTRIBUTE_GROUPS(cons_dev); 36231083a7beSTakashi Iwai 3624fbc92a34SKay Sievers static struct device *consdev; 3625fbc92a34SKay Sievers 3626fbc92a34SKay Sievers void console_sysfs_notify(void) 3627fbc92a34SKay Sievers { 3628fbc92a34SKay Sievers if (consdev) 3629fbc92a34SKay Sievers sysfs_notify(&consdev->kobj, NULL, "active"); 3630fbc92a34SKay Sievers } 3631fbc92a34SKay Sievers 363296fd7ce5SGreg Kroah-Hartman /* 363396fd7ce5SGreg Kroah-Hartman * Ok, now we can initialize the rest of the tty devices and can count 363496fd7ce5SGreg Kroah-Hartman * on memory allocations, interrupts etc.. 363596fd7ce5SGreg Kroah-Hartman */ 363696fd7ce5SGreg Kroah-Hartman int __init tty_init(void) 363796fd7ce5SGreg Kroah-Hartman { 363896fd7ce5SGreg Kroah-Hartman cdev_init(&tty_cdev, &tty_fops); 363996fd7ce5SGreg Kroah-Hartman if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || 364096fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) 364196fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/tty driver\n"); 3642fbc92a34SKay Sievers device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty"); 364396fd7ce5SGreg Kroah-Hartman 364496fd7ce5SGreg Kroah-Hartman cdev_init(&console_cdev, &console_fops); 364596fd7ce5SGreg Kroah-Hartman if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || 364696fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) 364796fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/console driver\n"); 36481083a7beSTakashi Iwai consdev = device_create_with_groups(tty_class, NULL, 36491083a7beSTakashi Iwai MKDEV(TTYAUX_MAJOR, 1), NULL, 36501083a7beSTakashi Iwai cons_dev_groups, "console"); 3651fbc92a34SKay Sievers if (IS_ERR(consdev)) 3652fbc92a34SKay Sievers consdev = NULL; 365396fd7ce5SGreg Kroah-Hartman 365496fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_VT 365596fd7ce5SGreg Kroah-Hartman vty_init(&console_fops); 365696fd7ce5SGreg Kroah-Hartman #endif 365796fd7ce5SGreg Kroah-Hartman return 0; 365896fd7ce5SGreg Kroah-Hartman } 365996fd7ce5SGreg Kroah-Hartman 3660