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 25996fd7ce5SGreg Kroah-Hartman int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 26096fd7ce5SGreg Kroah-Hartman const char *routine) 26196fd7ce5SGreg Kroah-Hartman { 26296fd7ce5SGreg Kroah-Hartman #ifdef TTY_PARANOIA_CHECK 26396fd7ce5SGreg Kroah-Hartman if (!tty) { 26496fd7ce5SGreg Kroah-Hartman printk(KERN_WARNING 26596fd7ce5SGreg Kroah-Hartman "null TTY for (%d:%d) in %s\n", 26696fd7ce5SGreg Kroah-Hartman imajor(inode), iminor(inode), routine); 26796fd7ce5SGreg Kroah-Hartman return 1; 26896fd7ce5SGreg Kroah-Hartman } 26996fd7ce5SGreg Kroah-Hartman if (tty->magic != TTY_MAGIC) { 27096fd7ce5SGreg Kroah-Hartman printk(KERN_WARNING 27196fd7ce5SGreg Kroah-Hartman "bad magic number for tty struct (%d:%d) in %s\n", 27296fd7ce5SGreg Kroah-Hartman imajor(inode), iminor(inode), routine); 27396fd7ce5SGreg Kroah-Hartman return 1; 27496fd7ce5SGreg Kroah-Hartman } 27596fd7ce5SGreg Kroah-Hartman #endif 27696fd7ce5SGreg Kroah-Hartman return 0; 27796fd7ce5SGreg Kroah-Hartman } 27896fd7ce5SGreg Kroah-Hartman 279deb287e7SPeter Hurley /* Caller must hold tty_lock */ 28096fd7ce5SGreg Kroah-Hartman static int check_tty_count(struct tty_struct *tty, const char *routine) 28196fd7ce5SGreg Kroah-Hartman { 28296fd7ce5SGreg Kroah-Hartman #ifdef CHECK_TTY_COUNT 28396fd7ce5SGreg Kroah-Hartman struct list_head *p; 28496fd7ce5SGreg Kroah-Hartman int count = 0; 28596fd7ce5SGreg Kroah-Hartman 28696fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 28796fd7ce5SGreg Kroah-Hartman list_for_each(p, &tty->tty_files) { 28896fd7ce5SGreg Kroah-Hartman count++; 28996fd7ce5SGreg Kroah-Hartman } 29096fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 29196fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 29296fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_SLAVE && 29396fd7ce5SGreg Kroah-Hartman tty->link && tty->link->count) 29496fd7ce5SGreg Kroah-Hartman count++; 29596fd7ce5SGreg Kroah-Hartman if (tty->count != count) { 29696fd7ce5SGreg Kroah-Hartman printk(KERN_WARNING "Warning: dev (%s) tty->count(%d) " 29796fd7ce5SGreg Kroah-Hartman "!= #fd's(%d) in %s\n", 29896fd7ce5SGreg Kroah-Hartman tty->name, tty->count, count, routine); 29996fd7ce5SGreg Kroah-Hartman return count; 30096fd7ce5SGreg Kroah-Hartman } 30196fd7ce5SGreg Kroah-Hartman #endif 30296fd7ce5SGreg Kroah-Hartman return 0; 30396fd7ce5SGreg Kroah-Hartman } 30496fd7ce5SGreg Kroah-Hartman 30596fd7ce5SGreg Kroah-Hartman /** 30696fd7ce5SGreg Kroah-Hartman * get_tty_driver - find device of a tty 30796fd7ce5SGreg Kroah-Hartman * @dev_t: device identifier 30896fd7ce5SGreg Kroah-Hartman * @index: returns the index of the tty 30996fd7ce5SGreg Kroah-Hartman * 31096fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a device number 31196fd7ce5SGreg Kroah-Hartman * and also passes back the index number. 31296fd7ce5SGreg Kroah-Hartman * 31396fd7ce5SGreg Kroah-Hartman * Locking: caller must hold tty_mutex 31496fd7ce5SGreg Kroah-Hartman */ 31596fd7ce5SGreg Kroah-Hartman 31696fd7ce5SGreg Kroah-Hartman static struct tty_driver *get_tty_driver(dev_t device, int *index) 31796fd7ce5SGreg Kroah-Hartman { 31896fd7ce5SGreg Kroah-Hartman struct tty_driver *p; 31996fd7ce5SGreg Kroah-Hartman 32096fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 32196fd7ce5SGreg Kroah-Hartman dev_t base = MKDEV(p->major, p->minor_start); 32296fd7ce5SGreg Kroah-Hartman if (device < base || device >= base + p->num) 32396fd7ce5SGreg Kroah-Hartman continue; 32496fd7ce5SGreg Kroah-Hartman *index = device - base; 32596fd7ce5SGreg Kroah-Hartman return tty_driver_kref_get(p); 32696fd7ce5SGreg Kroah-Hartman } 32796fd7ce5SGreg Kroah-Hartman return NULL; 32896fd7ce5SGreg Kroah-Hartman } 32996fd7ce5SGreg Kroah-Hartman 33096fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_CONSOLE_POLL 33196fd7ce5SGreg Kroah-Hartman 33296fd7ce5SGreg Kroah-Hartman /** 33396fd7ce5SGreg Kroah-Hartman * tty_find_polling_driver - find device of a polled tty 33496fd7ce5SGreg Kroah-Hartman * @name: name string to match 33596fd7ce5SGreg Kroah-Hartman * @line: pointer to resulting tty line nr 33696fd7ce5SGreg Kroah-Hartman * 33796fd7ce5SGreg Kroah-Hartman * This routine returns a tty driver structure, given a name 33896fd7ce5SGreg Kroah-Hartman * and the condition that the tty driver is capable of polled 33996fd7ce5SGreg Kroah-Hartman * operation. 34096fd7ce5SGreg Kroah-Hartman */ 34196fd7ce5SGreg Kroah-Hartman struct tty_driver *tty_find_polling_driver(char *name, int *line) 34296fd7ce5SGreg Kroah-Hartman { 34396fd7ce5SGreg Kroah-Hartman struct tty_driver *p, *res = NULL; 34496fd7ce5SGreg Kroah-Hartman int tty_line = 0; 34596fd7ce5SGreg Kroah-Hartman int len; 34696fd7ce5SGreg Kroah-Hartman char *str, *stp; 34796fd7ce5SGreg Kroah-Hartman 34896fd7ce5SGreg Kroah-Hartman for (str = name; *str; str++) 34996fd7ce5SGreg Kroah-Hartman if ((*str >= '0' && *str <= '9') || *str == ',') 35096fd7ce5SGreg Kroah-Hartman break; 35196fd7ce5SGreg Kroah-Hartman if (!*str) 35296fd7ce5SGreg Kroah-Hartman return NULL; 35396fd7ce5SGreg Kroah-Hartman 35496fd7ce5SGreg Kroah-Hartman len = str - name; 35596fd7ce5SGreg Kroah-Hartman tty_line = simple_strtoul(str, &str, 10); 35696fd7ce5SGreg Kroah-Hartman 35796fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 35896fd7ce5SGreg Kroah-Hartman /* Search through the tty devices to look for a match */ 35996fd7ce5SGreg Kroah-Hartman list_for_each_entry(p, &tty_drivers, tty_drivers) { 36096fd7ce5SGreg Kroah-Hartman if (strncmp(name, p->name, len) != 0) 36196fd7ce5SGreg Kroah-Hartman continue; 36296fd7ce5SGreg Kroah-Hartman stp = str; 36396fd7ce5SGreg Kroah-Hartman if (*stp == ',') 36496fd7ce5SGreg Kroah-Hartman stp++; 36596fd7ce5SGreg Kroah-Hartman if (*stp == '\0') 36696fd7ce5SGreg Kroah-Hartman stp = NULL; 36796fd7ce5SGreg Kroah-Hartman 36896fd7ce5SGreg Kroah-Hartman if (tty_line >= 0 && tty_line < p->num && p->ops && 36996fd7ce5SGreg Kroah-Hartman p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { 37096fd7ce5SGreg Kroah-Hartman res = tty_driver_kref_get(p); 37196fd7ce5SGreg Kroah-Hartman *line = tty_line; 37296fd7ce5SGreg Kroah-Hartman break; 37396fd7ce5SGreg Kroah-Hartman } 37496fd7ce5SGreg Kroah-Hartman } 37596fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 37696fd7ce5SGreg Kroah-Hartman 37796fd7ce5SGreg Kroah-Hartman return res; 37896fd7ce5SGreg Kroah-Hartman } 37996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_find_polling_driver); 38096fd7ce5SGreg Kroah-Hartman #endif 38196fd7ce5SGreg Kroah-Hartman 38296fd7ce5SGreg Kroah-Hartman /** 38396fd7ce5SGreg Kroah-Hartman * tty_check_change - check for POSIX terminal changes 38496fd7ce5SGreg Kroah-Hartman * @tty: tty to check 38596fd7ce5SGreg Kroah-Hartman * 38696fd7ce5SGreg Kroah-Hartman * If we try to write to, or set the state of, a terminal and we're 38796fd7ce5SGreg Kroah-Hartman * not in the foreground, send a SIGTTOU. If the signal is blocked or 38896fd7ce5SGreg Kroah-Hartman * ignored, go ahead and perform the operation. (POSIX 7.2) 38996fd7ce5SGreg Kroah-Hartman * 39096fd7ce5SGreg Kroah-Hartman * Locking: ctrl_lock 39196fd7ce5SGreg Kroah-Hartman */ 39296fd7ce5SGreg Kroah-Hartman 3932812d9e9SPeter Hurley int __tty_check_change(struct tty_struct *tty, int sig) 39496fd7ce5SGreg Kroah-Hartman { 39596fd7ce5SGreg Kroah-Hartman unsigned long flags; 3962812d9e9SPeter Hurley struct pid *pgrp, *tty_pgrp; 39796fd7ce5SGreg Kroah-Hartman int ret = 0; 39896fd7ce5SGreg Kroah-Hartman 39996fd7ce5SGreg Kroah-Hartman if (current->signal->tty != tty) 40096fd7ce5SGreg Kroah-Hartman return 0; 40196fd7ce5SGreg Kroah-Hartman 4026719693cSPatrick Donnelly rcu_read_lock(); 4036719693cSPatrick Donnelly pgrp = task_pgrp(current); 4046719693cSPatrick Donnelly 40596fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 4062812d9e9SPeter Hurley tty_pgrp = tty->pgrp; 40796fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 4086719693cSPatrick Donnelly 4092812d9e9SPeter Hurley if (tty_pgrp && pgrp != tty->pgrp) { 4102812d9e9SPeter Hurley if (is_ignored(sig)) { 4112812d9e9SPeter Hurley if (sig == SIGTTIN) 41296fd7ce5SGreg Kroah-Hartman ret = -EIO; 4132812d9e9SPeter Hurley } else if (is_current_pgrp_orphaned()) 4142812d9e9SPeter Hurley ret = -EIO; 4152812d9e9SPeter Hurley else { 4162812d9e9SPeter Hurley kill_pgrp(pgrp, sig, 1); 41796fd7ce5SGreg Kroah-Hartman set_thread_flag(TIF_SIGPENDING); 41896fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 4192812d9e9SPeter Hurley } 4202812d9e9SPeter Hurley } 4216719693cSPatrick Donnelly rcu_read_unlock(); 4222812d9e9SPeter Hurley 4232812d9e9SPeter Hurley if (!tty_pgrp) { 4242812d9e9SPeter Hurley pr_warn("%s: tty_check_change: sig=%d, tty->pgrp == NULL!\n", 4252812d9e9SPeter Hurley tty_name(tty), sig); 4262812d9e9SPeter Hurley } 4272812d9e9SPeter Hurley 42896fd7ce5SGreg Kroah-Hartman return ret; 42996fd7ce5SGreg Kroah-Hartman } 43096fd7ce5SGreg Kroah-Hartman 4312812d9e9SPeter Hurley int tty_check_change(struct tty_struct *tty) 4322812d9e9SPeter Hurley { 4332812d9e9SPeter Hurley return __tty_check_change(tty, SIGTTOU); 4342812d9e9SPeter Hurley } 43596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_check_change); 43696fd7ce5SGreg Kroah-Hartman 43796fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_read(struct file *file, char __user *buf, 43896fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 43996fd7ce5SGreg Kroah-Hartman { 44096fd7ce5SGreg Kroah-Hartman return 0; 44196fd7ce5SGreg Kroah-Hartman } 44296fd7ce5SGreg Kroah-Hartman 44396fd7ce5SGreg Kroah-Hartman static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, 44496fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 44596fd7ce5SGreg Kroah-Hartman { 44696fd7ce5SGreg Kroah-Hartman return -EIO; 44796fd7ce5SGreg Kroah-Hartman } 44896fd7ce5SGreg Kroah-Hartman 44996fd7ce5SGreg Kroah-Hartman /* No kernel lock held - none needed ;) */ 45096fd7ce5SGreg Kroah-Hartman static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait) 45196fd7ce5SGreg Kroah-Hartman { 45296fd7ce5SGreg Kroah-Hartman return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; 45396fd7ce5SGreg Kroah-Hartman } 45496fd7ce5SGreg Kroah-Hartman 45596fd7ce5SGreg Kroah-Hartman static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, 45696fd7ce5SGreg Kroah-Hartman unsigned long arg) 45796fd7ce5SGreg Kroah-Hartman { 45896fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 45996fd7ce5SGreg Kroah-Hartman } 46096fd7ce5SGreg Kroah-Hartman 46196fd7ce5SGreg Kroah-Hartman static long hung_up_tty_compat_ioctl(struct file *file, 46296fd7ce5SGreg Kroah-Hartman unsigned int cmd, unsigned long arg) 46396fd7ce5SGreg Kroah-Hartman { 46496fd7ce5SGreg Kroah-Hartman return cmd == TIOCSPGRP ? -ENOTTY : -EIO; 46596fd7ce5SGreg Kroah-Hartman } 46696fd7ce5SGreg Kroah-Hartman 46796fd7ce5SGreg Kroah-Hartman static const struct file_operations tty_fops = { 46896fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 46996fd7ce5SGreg Kroah-Hartman .read = tty_read, 47096fd7ce5SGreg Kroah-Hartman .write = tty_write, 47196fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 47296fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 47396fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 47496fd7ce5SGreg Kroah-Hartman .open = tty_open, 47596fd7ce5SGreg Kroah-Hartman .release = tty_release, 47696fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 47796fd7ce5SGreg Kroah-Hartman }; 47896fd7ce5SGreg Kroah-Hartman 47996fd7ce5SGreg Kroah-Hartman static const struct file_operations console_fops = { 48096fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 48196fd7ce5SGreg Kroah-Hartman .read = tty_read, 48296fd7ce5SGreg Kroah-Hartman .write = redirected_tty_write, 48396fd7ce5SGreg Kroah-Hartman .poll = tty_poll, 48496fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = tty_ioctl, 48596fd7ce5SGreg Kroah-Hartman .compat_ioctl = tty_compat_ioctl, 48696fd7ce5SGreg Kroah-Hartman .open = tty_open, 48796fd7ce5SGreg Kroah-Hartman .release = tty_release, 48896fd7ce5SGreg Kroah-Hartman .fasync = tty_fasync, 48996fd7ce5SGreg Kroah-Hartman }; 49096fd7ce5SGreg Kroah-Hartman 49196fd7ce5SGreg Kroah-Hartman static const struct file_operations hung_up_tty_fops = { 49296fd7ce5SGreg Kroah-Hartman .llseek = no_llseek, 49396fd7ce5SGreg Kroah-Hartman .read = hung_up_tty_read, 49496fd7ce5SGreg Kroah-Hartman .write = hung_up_tty_write, 49596fd7ce5SGreg Kroah-Hartman .poll = hung_up_tty_poll, 49696fd7ce5SGreg Kroah-Hartman .unlocked_ioctl = hung_up_tty_ioctl, 49796fd7ce5SGreg Kroah-Hartman .compat_ioctl = hung_up_tty_compat_ioctl, 49896fd7ce5SGreg Kroah-Hartman .release = tty_release, 49996fd7ce5SGreg Kroah-Hartman }; 50096fd7ce5SGreg Kroah-Hartman 50196fd7ce5SGreg Kroah-Hartman static DEFINE_SPINLOCK(redirect_lock); 50296fd7ce5SGreg Kroah-Hartman static struct file *redirect; 50396fd7ce5SGreg Kroah-Hartman 50411d9befdSPeter Hurley 50511d9befdSPeter Hurley void proc_clear_tty(struct task_struct *p) 50611d9befdSPeter Hurley { 50711d9befdSPeter Hurley unsigned long flags; 50811d9befdSPeter Hurley struct tty_struct *tty; 50911d9befdSPeter Hurley spin_lock_irqsave(&p->sighand->siglock, flags); 51011d9befdSPeter Hurley tty = p->signal->tty; 51111d9befdSPeter Hurley p->signal->tty = NULL; 51211d9befdSPeter Hurley spin_unlock_irqrestore(&p->sighand->siglock, flags); 51311d9befdSPeter Hurley tty_kref_put(tty); 51411d9befdSPeter Hurley } 51511d9befdSPeter Hurley 5162c411c11SPeter Hurley /** 5172c411c11SPeter Hurley * proc_set_tty - set the controlling terminal 5182c411c11SPeter Hurley * 5192c411c11SPeter Hurley * Only callable by the session leader and only if it does not already have 5202c411c11SPeter Hurley * a controlling terminal. 5212c411c11SPeter Hurley * 522e218eb32SPeter Hurley * Caller must hold: tty_lock() 523e218eb32SPeter Hurley * a readlock on tasklist_lock 5242c411c11SPeter Hurley * sighand lock 5252c411c11SPeter Hurley */ 526bce65f18SPeter Hurley static void __proc_set_tty(struct tty_struct *tty) 52711d9befdSPeter Hurley { 52811d9befdSPeter Hurley unsigned long flags; 529ae28fa72SPeter Hurley 53011d9befdSPeter Hurley spin_lock_irqsave(&tty->ctrl_lock, flags); 531a361858dSPeter Hurley /* 532a361858dSPeter Hurley * The session and fg pgrp references will be non-NULL if 533a361858dSPeter Hurley * tiocsctty() is stealing the controlling tty 534a361858dSPeter Hurley */ 53511d9befdSPeter Hurley put_pid(tty->session); 53611d9befdSPeter Hurley put_pid(tty->pgrp); 537bce65f18SPeter Hurley tty->pgrp = get_pid(task_pgrp(current)); 53811d9befdSPeter Hurley spin_unlock_irqrestore(&tty->ctrl_lock, flags); 539bce65f18SPeter Hurley tty->session = get_pid(task_session(current)); 540bce65f18SPeter Hurley if (current->signal->tty) { 541e2dfa3d3SPeter Hurley tty_debug(tty, "current tty %s not NULL!!\n", 542e2dfa3d3SPeter Hurley current->signal->tty->name); 543bce65f18SPeter Hurley tty_kref_put(current->signal->tty); 54411d9befdSPeter Hurley } 545bce65f18SPeter Hurley put_pid(current->signal->tty_old_pgrp); 546bce65f18SPeter Hurley current->signal->tty = tty_kref_get(tty); 547bce65f18SPeter Hurley current->signal->tty_old_pgrp = NULL; 54811d9befdSPeter Hurley } 54911d9befdSPeter Hurley 550bce65f18SPeter Hurley static void proc_set_tty(struct tty_struct *tty) 55111d9befdSPeter Hurley { 552bce65f18SPeter Hurley spin_lock_irq(¤t->sighand->siglock); 553bce65f18SPeter Hurley __proc_set_tty(tty); 554bce65f18SPeter Hurley spin_unlock_irq(¤t->sighand->siglock); 55511d9befdSPeter Hurley } 55611d9befdSPeter Hurley 55711d9befdSPeter Hurley struct tty_struct *get_current_tty(void) 55811d9befdSPeter Hurley { 55911d9befdSPeter Hurley struct tty_struct *tty; 56011d9befdSPeter Hurley unsigned long flags; 56111d9befdSPeter Hurley 56211d9befdSPeter Hurley spin_lock_irqsave(¤t->sighand->siglock, flags); 56311d9befdSPeter Hurley tty = tty_kref_get(current->signal->tty); 56411d9befdSPeter Hurley spin_unlock_irqrestore(¤t->sighand->siglock, flags); 56511d9befdSPeter Hurley return tty; 56611d9befdSPeter Hurley } 56711d9befdSPeter Hurley EXPORT_SYMBOL_GPL(get_current_tty); 56811d9befdSPeter Hurley 56911d9befdSPeter Hurley static void session_clear_tty(struct pid *session) 57011d9befdSPeter Hurley { 57111d9befdSPeter Hurley struct task_struct *p; 57211d9befdSPeter Hurley do_each_pid_task(session, PIDTYPE_SID, p) { 57311d9befdSPeter Hurley proc_clear_tty(p); 57411d9befdSPeter Hurley } while_each_pid_task(session, PIDTYPE_SID, p); 57511d9befdSPeter Hurley } 57611d9befdSPeter Hurley 57796fd7ce5SGreg Kroah-Hartman /** 57896fd7ce5SGreg Kroah-Hartman * tty_wakeup - request more data 57996fd7ce5SGreg Kroah-Hartman * @tty: terminal 58096fd7ce5SGreg Kroah-Hartman * 58196fd7ce5SGreg Kroah-Hartman * Internal and external helper for wakeups of tty. This function 58296fd7ce5SGreg Kroah-Hartman * informs the line discipline if present that the driver is ready 58396fd7ce5SGreg Kroah-Hartman * to receive more output data. 58496fd7ce5SGreg Kroah-Hartman */ 58596fd7ce5SGreg Kroah-Hartman 58696fd7ce5SGreg Kroah-Hartman void tty_wakeup(struct tty_struct *tty) 58796fd7ce5SGreg Kroah-Hartman { 58896fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 58996fd7ce5SGreg Kroah-Hartman 59096fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { 59196fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref(tty); 59296fd7ce5SGreg Kroah-Hartman if (ld) { 59396fd7ce5SGreg Kroah-Hartman if (ld->ops->write_wakeup) 59496fd7ce5SGreg Kroah-Hartman ld->ops->write_wakeup(tty); 59596fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 59696fd7ce5SGreg Kroah-Hartman } 59796fd7ce5SGreg Kroah-Hartman } 59896fd7ce5SGreg Kroah-Hartman wake_up_interruptible_poll(&tty->write_wait, POLLOUT); 59996fd7ce5SGreg Kroah-Hartman } 60096fd7ce5SGreg Kroah-Hartman 60196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_wakeup); 60296fd7ce5SGreg Kroah-Hartman 60396fd7ce5SGreg Kroah-Hartman /** 604ea648a47SPeter Hurley * tty_signal_session_leader - sends SIGHUP to session leader 605f91e2590SPeter Hurley * @tty controlling tty 606f91e2590SPeter Hurley * @exit_session if non-zero, signal all foreground group processes 607ea648a47SPeter Hurley * 608f91e2590SPeter Hurley * Send SIGHUP and SIGCONT to the session leader and its process group. 609f91e2590SPeter Hurley * Optionally, signal all processes in the foreground process group. 610ea648a47SPeter Hurley * 611ea648a47SPeter Hurley * Returns the number of processes in the session with this tty 612ea648a47SPeter Hurley * as their controlling terminal. This value is used to drop 613ea648a47SPeter Hurley * tty references for those processes. 614ea648a47SPeter Hurley */ 615f91e2590SPeter Hurley static int tty_signal_session_leader(struct tty_struct *tty, int exit_session) 616ea648a47SPeter Hurley { 617ea648a47SPeter Hurley struct task_struct *p; 618ea648a47SPeter Hurley int refs = 0; 619f91e2590SPeter Hurley struct pid *tty_pgrp = NULL; 620ea648a47SPeter Hurley 621ea648a47SPeter Hurley read_lock(&tasklist_lock); 622ea648a47SPeter Hurley if (tty->session) { 623ea648a47SPeter Hurley do_each_pid_task(tty->session, PIDTYPE_SID, p) { 624ea648a47SPeter Hurley spin_lock_irq(&p->sighand->siglock); 625ea648a47SPeter Hurley if (p->signal->tty == tty) { 626ea648a47SPeter Hurley p->signal->tty = NULL; 627ea648a47SPeter Hurley /* We defer the dereferences outside fo 628ea648a47SPeter Hurley the tasklist lock */ 629ea648a47SPeter Hurley refs++; 630ea648a47SPeter Hurley } 631ea648a47SPeter Hurley if (!p->signal->leader) { 632ea648a47SPeter Hurley spin_unlock_irq(&p->sighand->siglock); 633ea648a47SPeter Hurley continue; 634ea648a47SPeter Hurley } 635ea648a47SPeter Hurley __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); 636ea648a47SPeter Hurley __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); 637ea648a47SPeter Hurley put_pid(p->signal->tty_old_pgrp); /* A noop */ 638bc30c3b2SPeter Hurley spin_lock(&tty->ctrl_lock); 639f91e2590SPeter Hurley tty_pgrp = get_pid(tty->pgrp); 640ea648a47SPeter Hurley if (tty->pgrp) 641ea648a47SPeter Hurley p->signal->tty_old_pgrp = get_pid(tty->pgrp); 642bc30c3b2SPeter Hurley spin_unlock(&tty->ctrl_lock); 643ea648a47SPeter Hurley spin_unlock_irq(&p->sighand->siglock); 644ea648a47SPeter Hurley } while_each_pid_task(tty->session, PIDTYPE_SID, p); 645ea648a47SPeter Hurley } 646ea648a47SPeter Hurley read_unlock(&tasklist_lock); 647ea648a47SPeter Hurley 648f91e2590SPeter Hurley if (tty_pgrp) { 649f91e2590SPeter Hurley if (exit_session) 650f91e2590SPeter Hurley kill_pgrp(tty_pgrp, SIGHUP, exit_session); 651f91e2590SPeter Hurley put_pid(tty_pgrp); 652f91e2590SPeter Hurley } 653f91e2590SPeter Hurley 654ea648a47SPeter Hurley return refs; 655ea648a47SPeter Hurley } 656ea648a47SPeter Hurley 657ea648a47SPeter Hurley /** 65896fd7ce5SGreg Kroah-Hartman * __tty_hangup - actual handler for hangup events 65996fd7ce5SGreg Kroah-Hartman * @work: tty device 66096fd7ce5SGreg Kroah-Hartman * 661ef4f527cSKevin Cernekee * This can be called by a "kworker" kernel thread. That is process 66296fd7ce5SGreg Kroah-Hartman * synchronous but doesn't hold any locks, so we need to make sure we 66396fd7ce5SGreg Kroah-Hartman * have the appropriate locks for what we're doing. 66496fd7ce5SGreg Kroah-Hartman * 66596fd7ce5SGreg Kroah-Hartman * The hangup event clears any pending redirections onto the hung up 66696fd7ce5SGreg Kroah-Hartman * device. It ensures future writes will error and it does the needed 66796fd7ce5SGreg Kroah-Hartman * line discipline hangup and signal delivery. The tty object itself 66896fd7ce5SGreg Kroah-Hartman * remains intact. 66996fd7ce5SGreg Kroah-Hartman * 67096fd7ce5SGreg Kroah-Hartman * Locking: 67196fd7ce5SGreg Kroah-Hartman * BTM 67296fd7ce5SGreg Kroah-Hartman * redirect lock for undoing redirection 67396fd7ce5SGreg Kroah-Hartman * file list lock for manipulating list of ttys 674137084bbSPeter Hurley * tty_ldiscs_lock from called functions 6756a1c0680SPeter Hurley * termios_rwsem resetting termios data 67696fd7ce5SGreg Kroah-Hartman * tasklist_lock to walk task list for hangup event 67796fd7ce5SGreg Kroah-Hartman * ->siglock to protect ->signal/->sighand 67896fd7ce5SGreg Kroah-Hartman */ 679f91e2590SPeter Hurley static void __tty_hangup(struct tty_struct *tty, int exit_session) 68096fd7ce5SGreg Kroah-Hartman { 68196fd7ce5SGreg Kroah-Hartman struct file *cons_filp = NULL; 68296fd7ce5SGreg Kroah-Hartman struct file *filp, *f = NULL; 68396fd7ce5SGreg Kroah-Hartman struct tty_file_private *priv; 68496fd7ce5SGreg Kroah-Hartman int closecount = 0, n; 685ea648a47SPeter Hurley int refs; 68696fd7ce5SGreg Kroah-Hartman 68796fd7ce5SGreg Kroah-Hartman if (!tty) 68896fd7ce5SGreg Kroah-Hartman return; 68996fd7ce5SGreg Kroah-Hartman 69096fd7ce5SGreg Kroah-Hartman 69196fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 69296fd7ce5SGreg Kroah-Hartman if (redirect && file_tty(redirect) == tty) { 69396fd7ce5SGreg Kroah-Hartman f = redirect; 69496fd7ce5SGreg Kroah-Hartman redirect = NULL; 69596fd7ce5SGreg Kroah-Hartman } 69696fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 69796fd7ce5SGreg Kroah-Hartman 69889c8d91eSAlan Cox tty_lock(tty); 69996fd7ce5SGreg Kroah-Hartman 700cb50e523SPeter Hurley if (test_bit(TTY_HUPPED, &tty->flags)) { 701cb50e523SPeter Hurley tty_unlock(tty); 702cb50e523SPeter Hurley return; 703cb50e523SPeter Hurley } 704cb50e523SPeter Hurley 70596fd7ce5SGreg Kroah-Hartman /* inuse_filps is protected by the single tty lock, 70696fd7ce5SGreg Kroah-Hartman this really needs to change if we want to flush the 70796fd7ce5SGreg Kroah-Hartman workqueue with the lock held */ 70896fd7ce5SGreg Kroah-Hartman check_tty_count(tty, "tty_hangup"); 70996fd7ce5SGreg Kroah-Hartman 71096fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 71196fd7ce5SGreg Kroah-Hartman /* This breaks for file handles being sent over AF_UNIX sockets ? */ 71296fd7ce5SGreg Kroah-Hartman list_for_each_entry(priv, &tty->tty_files, list) { 71396fd7ce5SGreg Kroah-Hartman filp = priv->file; 71496fd7ce5SGreg Kroah-Hartman if (filp->f_op->write == redirected_tty_write) 71596fd7ce5SGreg Kroah-Hartman cons_filp = filp; 71696fd7ce5SGreg Kroah-Hartman if (filp->f_op->write != tty_write) 71796fd7ce5SGreg Kroah-Hartman continue; 71896fd7ce5SGreg Kroah-Hartman closecount++; 71996fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); /* can't block */ 72096fd7ce5SGreg Kroah-Hartman filp->f_op = &hung_up_tty_fops; 72196fd7ce5SGreg Kroah-Hartman } 72296fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 72396fd7ce5SGreg Kroah-Hartman 72425fdf243SPeter Hurley refs = tty_signal_session_leader(tty, exit_session); 72525fdf243SPeter Hurley /* Account for the p->signal references we killed */ 72625fdf243SPeter Hurley while (refs--) 72725fdf243SPeter Hurley tty_kref_put(tty); 72825fdf243SPeter Hurley 72996fd7ce5SGreg Kroah-Hartman tty_ldisc_hangup(tty); 73096fd7ce5SGreg Kroah-Hartman 73120cc225bSPeter Hurley spin_lock_irq(&tty->ctrl_lock); 73296fd7ce5SGreg Kroah-Hartman clear_bit(TTY_THROTTLED, &tty->flags); 73396fd7ce5SGreg Kroah-Hartman clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 73496fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 73596fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 73696fd7ce5SGreg Kroah-Hartman tty->session = NULL; 73796fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 73896fd7ce5SGreg Kroah-Hartman tty->ctrl_status = 0; 73920cc225bSPeter Hurley spin_unlock_irq(&tty->ctrl_lock); 74096fd7ce5SGreg Kroah-Hartman 74196fd7ce5SGreg Kroah-Hartman /* 74296fd7ce5SGreg Kroah-Hartman * If one of the devices matches a console pointer, we 74396fd7ce5SGreg Kroah-Hartman * cannot just call hangup() because that will cause 74496fd7ce5SGreg Kroah-Hartman * tty->count and state->count to go out of sync. 74596fd7ce5SGreg Kroah-Hartman * So we just call close() the right number of times. 74696fd7ce5SGreg Kroah-Hartman */ 74796fd7ce5SGreg Kroah-Hartman if (cons_filp) { 74896fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 74996fd7ce5SGreg Kroah-Hartman for (n = 0; n < closecount; n++) 75096fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, cons_filp); 75196fd7ce5SGreg Kroah-Hartman } else if (tty->ops->hangup) 7527c6d340fSPeter Hurley tty->ops->hangup(tty); 75396fd7ce5SGreg Kroah-Hartman /* 75496fd7ce5SGreg Kroah-Hartman * We don't want to have driver/ldisc interactions beyond 75596fd7ce5SGreg Kroah-Hartman * the ones we did here. The driver layer expects no 75696fd7ce5SGreg Kroah-Hartman * calls after ->hangup() from the ldisc side. However we 75796fd7ce5SGreg Kroah-Hartman * can't yet guarantee all that. 75896fd7ce5SGreg Kroah-Hartman */ 75996fd7ce5SGreg Kroah-Hartman set_bit(TTY_HUPPED, &tty->flags); 76089c8d91eSAlan Cox tty_unlock(tty); 76196fd7ce5SGreg Kroah-Hartman 76296fd7ce5SGreg Kroah-Hartman if (f) 76396fd7ce5SGreg Kroah-Hartman fput(f); 76496fd7ce5SGreg Kroah-Hartman } 76596fd7ce5SGreg Kroah-Hartman 76696fd7ce5SGreg Kroah-Hartman static void do_tty_hangup(struct work_struct *work) 76796fd7ce5SGreg Kroah-Hartman { 76896fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 76996fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 77096fd7ce5SGreg Kroah-Hartman 771f91e2590SPeter Hurley __tty_hangup(tty, 0); 77296fd7ce5SGreg Kroah-Hartman } 77396fd7ce5SGreg Kroah-Hartman 77496fd7ce5SGreg Kroah-Hartman /** 77596fd7ce5SGreg Kroah-Hartman * tty_hangup - trigger a hangup event 77696fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 77796fd7ce5SGreg Kroah-Hartman * 77896fd7ce5SGreg Kroah-Hartman * A carrier loss (virtual or otherwise) has occurred on this like 77996fd7ce5SGreg Kroah-Hartman * schedule a hangup sequence to run after this event. 78096fd7ce5SGreg Kroah-Hartman */ 78196fd7ce5SGreg Kroah-Hartman 78296fd7ce5SGreg Kroah-Hartman void tty_hangup(struct tty_struct *tty) 78396fd7ce5SGreg Kroah-Hartman { 784accff793SPeter Hurley tty_debug_hangup(tty, "\n"); 78596fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 78696fd7ce5SGreg Kroah-Hartman } 78796fd7ce5SGreg Kroah-Hartman 78896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hangup); 78996fd7ce5SGreg Kroah-Hartman 79096fd7ce5SGreg Kroah-Hartman /** 79196fd7ce5SGreg Kroah-Hartman * tty_vhangup - process vhangup 79296fd7ce5SGreg Kroah-Hartman * @tty: tty to hangup 79396fd7ce5SGreg Kroah-Hartman * 79496fd7ce5SGreg Kroah-Hartman * The user has asked via system call for the terminal to be hung up. 79596fd7ce5SGreg Kroah-Hartman * We do this synchronously so that when the syscall returns the process 79696fd7ce5SGreg Kroah-Hartman * is complete. That guarantee is necessary for security reasons. 79796fd7ce5SGreg Kroah-Hartman */ 79896fd7ce5SGreg Kroah-Hartman 79996fd7ce5SGreg Kroah-Hartman void tty_vhangup(struct tty_struct *tty) 80096fd7ce5SGreg Kroah-Hartman { 801accff793SPeter Hurley tty_debug_hangup(tty, "\n"); 802f91e2590SPeter Hurley __tty_hangup(tty, 0); 80396fd7ce5SGreg Kroah-Hartman } 80496fd7ce5SGreg Kroah-Hartman 80596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_vhangup); 80696fd7ce5SGreg Kroah-Hartman 80796fd7ce5SGreg Kroah-Hartman 80896fd7ce5SGreg Kroah-Hartman /** 80996fd7ce5SGreg Kroah-Hartman * tty_vhangup_self - process vhangup for own ctty 81096fd7ce5SGreg Kroah-Hartman * 81196fd7ce5SGreg Kroah-Hartman * Perform a vhangup on the current controlling tty 81296fd7ce5SGreg Kroah-Hartman */ 81396fd7ce5SGreg Kroah-Hartman 81496fd7ce5SGreg Kroah-Hartman void tty_vhangup_self(void) 81596fd7ce5SGreg Kroah-Hartman { 81696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 81796fd7ce5SGreg Kroah-Hartman 81896fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 81996fd7ce5SGreg Kroah-Hartman if (tty) { 82096fd7ce5SGreg Kroah-Hartman tty_vhangup(tty); 82196fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 82296fd7ce5SGreg Kroah-Hartman } 82396fd7ce5SGreg Kroah-Hartman } 82496fd7ce5SGreg Kroah-Hartman 82596fd7ce5SGreg Kroah-Hartman /** 826f91e2590SPeter Hurley * tty_vhangup_session - hangup session leader exit 827f91e2590SPeter Hurley * @tty: tty to hangup 828f91e2590SPeter Hurley * 829f91e2590SPeter Hurley * The session leader is exiting and hanging up its controlling terminal. 830f91e2590SPeter Hurley * Every process in the foreground process group is signalled SIGHUP. 831f91e2590SPeter Hurley * 832f91e2590SPeter Hurley * We do this synchronously so that when the syscall returns the process 833f91e2590SPeter Hurley * is complete. That guarantee is necessary for security reasons. 834f91e2590SPeter Hurley */ 835f91e2590SPeter Hurley 83644a459fdSChanglong Xie static void tty_vhangup_session(struct tty_struct *tty) 837f91e2590SPeter Hurley { 838accff793SPeter Hurley tty_debug_hangup(tty, "\n"); 839f91e2590SPeter Hurley __tty_hangup(tty, 1); 840f91e2590SPeter Hurley } 841f91e2590SPeter Hurley 842f91e2590SPeter Hurley /** 84396fd7ce5SGreg Kroah-Hartman * tty_hung_up_p - was tty hung up 84496fd7ce5SGreg Kroah-Hartman * @filp: file pointer of tty 84596fd7ce5SGreg Kroah-Hartman * 84696fd7ce5SGreg Kroah-Hartman * Return true if the tty has been subject to a vhangup or a carrier 84796fd7ce5SGreg Kroah-Hartman * loss 84896fd7ce5SGreg Kroah-Hartman */ 84996fd7ce5SGreg Kroah-Hartman 85096fd7ce5SGreg Kroah-Hartman int tty_hung_up_p(struct file *filp) 85196fd7ce5SGreg Kroah-Hartman { 85296fd7ce5SGreg Kroah-Hartman return (filp->f_op == &hung_up_tty_fops); 85396fd7ce5SGreg Kroah-Hartman } 85496fd7ce5SGreg Kroah-Hartman 85596fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_hung_up_p); 85696fd7ce5SGreg Kroah-Hartman 85796fd7ce5SGreg Kroah-Hartman /** 85896fd7ce5SGreg Kroah-Hartman * disassociate_ctty - disconnect controlling tty 85996fd7ce5SGreg Kroah-Hartman * @on_exit: true if exiting so need to "hang up" the session 86096fd7ce5SGreg Kroah-Hartman * 86196fd7ce5SGreg Kroah-Hartman * This function is typically called only by the session leader, when 86296fd7ce5SGreg Kroah-Hartman * it wants to disassociate itself from its controlling tty. 86396fd7ce5SGreg Kroah-Hartman * 86496fd7ce5SGreg Kroah-Hartman * It performs the following functions: 86596fd7ce5SGreg Kroah-Hartman * (1) Sends a SIGHUP and SIGCONT to the foreground process group 86696fd7ce5SGreg Kroah-Hartman * (2) Clears the tty from being controlling the session 86796fd7ce5SGreg Kroah-Hartman * (3) Clears the controlling tty for all processes in the 86896fd7ce5SGreg Kroah-Hartman * session group. 86996fd7ce5SGreg Kroah-Hartman * 87096fd7ce5SGreg Kroah-Hartman * The argument on_exit is set to 1 if called when a process is 87196fd7ce5SGreg Kroah-Hartman * exiting; it is 0 if called by the ioctl TIOCNOTTY. 87296fd7ce5SGreg Kroah-Hartman * 87396fd7ce5SGreg Kroah-Hartman * Locking: 87496fd7ce5SGreg Kroah-Hartman * BTM is taken for hysterical raisins, and held when 87596fd7ce5SGreg Kroah-Hartman * called from no_tty(). 87696fd7ce5SGreg Kroah-Hartman * tty_mutex is taken to protect tty 87796fd7ce5SGreg Kroah-Hartman * ->siglock is taken to protect ->signal/->sighand 87896fd7ce5SGreg Kroah-Hartman * tasklist_lock is taken to walk process list for sessions 87996fd7ce5SGreg Kroah-Hartman * ->siglock is taken to protect ->signal/->sighand 88096fd7ce5SGreg Kroah-Hartman */ 88196fd7ce5SGreg Kroah-Hartman 88296fd7ce5SGreg Kroah-Hartman void disassociate_ctty(int on_exit) 88396fd7ce5SGreg Kroah-Hartman { 88496fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 88596fd7ce5SGreg Kroah-Hartman 88696fd7ce5SGreg Kroah-Hartman if (!current->signal->leader) 88796fd7ce5SGreg Kroah-Hartman return; 88896fd7ce5SGreg Kroah-Hartman 88996fd7ce5SGreg Kroah-Hartman tty = get_current_tty(); 89096fd7ce5SGreg Kroah-Hartman if (tty) { 891f91e2590SPeter Hurley if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) { 892f91e2590SPeter Hurley tty_vhangup_session(tty); 893f91e2590SPeter Hurley } else { 894f91e2590SPeter Hurley struct pid *tty_pgrp = tty_get_pgrp(tty); 8951411dc4aSJiri Slaby if (tty_pgrp) { 8961411dc4aSJiri Slaby kill_pgrp(tty_pgrp, SIGHUP, on_exit); 89703e12617SOleg Nesterov if (!on_exit) 8981411dc4aSJiri Slaby kill_pgrp(tty_pgrp, SIGCONT, on_exit); 8991411dc4aSJiri Slaby put_pid(tty_pgrp); 9001411dc4aSJiri Slaby } 901f91e2590SPeter Hurley } 902f91e2590SPeter Hurley tty_kref_put(tty); 903f91e2590SPeter Hurley 90496fd7ce5SGreg Kroah-Hartman } else if (on_exit) { 90596fd7ce5SGreg Kroah-Hartman struct pid *old_pgrp; 90696fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 90796fd7ce5SGreg Kroah-Hartman old_pgrp = current->signal->tty_old_pgrp; 90896fd7ce5SGreg Kroah-Hartman current->signal->tty_old_pgrp = NULL; 90996fd7ce5SGreg Kroah-Hartman spin_unlock_irq(¤t->sighand->siglock); 91096fd7ce5SGreg Kroah-Hartman if (old_pgrp) { 91196fd7ce5SGreg Kroah-Hartman kill_pgrp(old_pgrp, SIGHUP, on_exit); 91296fd7ce5SGreg Kroah-Hartman kill_pgrp(old_pgrp, SIGCONT, on_exit); 91396fd7ce5SGreg Kroah-Hartman put_pid(old_pgrp); 91496fd7ce5SGreg Kroah-Hartman } 91596fd7ce5SGreg Kroah-Hartman return; 91696fd7ce5SGreg Kroah-Hartman } 91796fd7ce5SGreg Kroah-Hartman 91896fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 91996fd7ce5SGreg Kroah-Hartman put_pid(current->signal->tty_old_pgrp); 92096fd7ce5SGreg Kroah-Hartman current->signal->tty_old_pgrp = NULL; 92196fd7ce5SGreg Kroah-Hartman 922c70dbb1eSChen Tingjie tty = tty_kref_get(current->signal->tty); 92396fd7ce5SGreg Kroah-Hartman if (tty) { 92496fd7ce5SGreg Kroah-Hartman unsigned long flags; 92596fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 92696fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 92796fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 92896fd7ce5SGreg Kroah-Hartman tty->session = NULL; 92996fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 93096fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 93196fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 932accff793SPeter Hurley } else 933accff793SPeter Hurley tty_debug_hangup(tty, "no current tty\n"); 93496fd7ce5SGreg Kroah-Hartman 935c70dbb1eSChen Tingjie spin_unlock_irq(¤t->sighand->siglock); 93696fd7ce5SGreg Kroah-Hartman /* Now clear signal->tty under the lock */ 93796fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 93896fd7ce5SGreg Kroah-Hartman session_clear_tty(task_session(current)); 93996fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 94096fd7ce5SGreg Kroah-Hartman } 94196fd7ce5SGreg Kroah-Hartman 94296fd7ce5SGreg Kroah-Hartman /** 94396fd7ce5SGreg Kroah-Hartman * 94496fd7ce5SGreg Kroah-Hartman * no_tty - Ensure the current process does not have a controlling tty 94596fd7ce5SGreg Kroah-Hartman */ 94696fd7ce5SGreg Kroah-Hartman void no_tty(void) 94796fd7ce5SGreg Kroah-Hartman { 9483af502b9SAlan Cox /* FIXME: Review locking here. The tty_lock never covered any race 9493af502b9SAlan Cox between a new association and proc_clear_tty but possible we need 9503af502b9SAlan Cox to protect against this anyway */ 95196fd7ce5SGreg Kroah-Hartman struct task_struct *tsk = current; 95296fd7ce5SGreg Kroah-Hartman disassociate_ctty(0); 95396fd7ce5SGreg Kroah-Hartman proc_clear_tty(tsk); 95496fd7ce5SGreg Kroah-Hartman } 95596fd7ce5SGreg Kroah-Hartman 95696fd7ce5SGreg Kroah-Hartman 95796fd7ce5SGreg Kroah-Hartman /** 95896fd7ce5SGreg Kroah-Hartman * stop_tty - propagate flow control 95996fd7ce5SGreg Kroah-Hartman * @tty: tty to stop 96096fd7ce5SGreg Kroah-Hartman * 96101adc807SPeter Hurley * Perform flow control to the driver. May be called 96296fd7ce5SGreg Kroah-Hartman * on an already stopped device and will not re-call the driver 96396fd7ce5SGreg Kroah-Hartman * method. 96496fd7ce5SGreg Kroah-Hartman * 96596fd7ce5SGreg Kroah-Hartman * This functionality is used by both the line disciplines for 96696fd7ce5SGreg Kroah-Hartman * halting incoming flow and by the driver. It may therefore be 96796fd7ce5SGreg Kroah-Hartman * called from any context, may be under the tty atomic_write_lock 96896fd7ce5SGreg Kroah-Hartman * but not always. 96996fd7ce5SGreg Kroah-Hartman * 97096fd7ce5SGreg Kroah-Hartman * Locking: 971f9e053dcSPeter Hurley * flow_lock 97296fd7ce5SGreg Kroah-Hartman */ 97396fd7ce5SGreg Kroah-Hartman 974f9e053dcSPeter Hurley void __stop_tty(struct tty_struct *tty) 97596fd7ce5SGreg Kroah-Hartman { 976f9e053dcSPeter Hurley if (tty->stopped) 97796fd7ce5SGreg Kroah-Hartman return; 97896fd7ce5SGreg Kroah-Hartman tty->stopped = 1; 97996fd7ce5SGreg Kroah-Hartman if (tty->ops->stop) 980c961bfb1SPeter Hurley tty->ops->stop(tty); 98196fd7ce5SGreg Kroah-Hartman } 98296fd7ce5SGreg Kroah-Hartman 983f9e053dcSPeter Hurley void stop_tty(struct tty_struct *tty) 984f9e053dcSPeter Hurley { 985f9e053dcSPeter Hurley unsigned long flags; 986f9e053dcSPeter Hurley 987f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 988f9e053dcSPeter Hurley __stop_tty(tty); 989f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 990f9e053dcSPeter Hurley } 99196fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(stop_tty); 99296fd7ce5SGreg Kroah-Hartman 99396fd7ce5SGreg Kroah-Hartman /** 99496fd7ce5SGreg Kroah-Hartman * start_tty - propagate flow control 99596fd7ce5SGreg Kroah-Hartman * @tty: tty to start 99696fd7ce5SGreg Kroah-Hartman * 99701adc807SPeter Hurley * Start a tty that has been stopped if at all possible. If this 99801adc807SPeter Hurley * tty was previous stopped and is now being started, the driver 99901adc807SPeter Hurley * start method is invoked and the line discipline woken. 100096fd7ce5SGreg Kroah-Hartman * 100196fd7ce5SGreg Kroah-Hartman * Locking: 1002f9e053dcSPeter Hurley * flow_lock 100396fd7ce5SGreg Kroah-Hartman */ 100496fd7ce5SGreg Kroah-Hartman 1005f9e053dcSPeter Hurley void __start_tty(struct tty_struct *tty) 100696fd7ce5SGreg Kroah-Hartman { 1007f9e053dcSPeter Hurley if (!tty->stopped || tty->flow_stopped) 100896fd7ce5SGreg Kroah-Hartman return; 100996fd7ce5SGreg Kroah-Hartman tty->stopped = 0; 101096fd7ce5SGreg Kroah-Hartman if (tty->ops->start) 1011c961bfb1SPeter Hurley tty->ops->start(tty); 101296fd7ce5SGreg Kroah-Hartman tty_wakeup(tty); 101396fd7ce5SGreg Kroah-Hartman } 101496fd7ce5SGreg Kroah-Hartman 1015f9e053dcSPeter Hurley void start_tty(struct tty_struct *tty) 1016f9e053dcSPeter Hurley { 1017f9e053dcSPeter Hurley unsigned long flags; 1018f9e053dcSPeter Hurley 1019f9e053dcSPeter Hurley spin_lock_irqsave(&tty->flow_lock, flags); 1020f9e053dcSPeter Hurley __start_tty(tty); 1021f9e053dcSPeter Hurley spin_unlock_irqrestore(&tty->flow_lock, flags); 1022f9e053dcSPeter Hurley } 102396fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(start_tty); 102496fd7ce5SGreg Kroah-Hartman 102537b7f3c7SJiri Slaby static void tty_update_time(struct timespec *time) 102637b7f3c7SJiri Slaby { 1027f0bf0bd0SJiri Slaby unsigned long sec = get_seconds(); 1028fbf47635SGreg Kroah-Hartman 1029fbf47635SGreg Kroah-Hartman /* 1030fbf47635SGreg Kroah-Hartman * We only care if the two values differ in anything other than the 1031fbf47635SGreg Kroah-Hartman * lower three bits (i.e every 8 seconds). If so, then we can update 1032fbf47635SGreg Kroah-Hartman * the time of the tty device, otherwise it could be construded as a 1033fbf47635SGreg Kroah-Hartman * security leak to let userspace know the exact timing of the tty. 1034fbf47635SGreg Kroah-Hartman */ 1035fbf47635SGreg Kroah-Hartman if ((sec ^ time->tv_sec) & ~7) 103637b7f3c7SJiri Slaby time->tv_sec = sec; 103737b7f3c7SJiri Slaby } 103837b7f3c7SJiri Slaby 103996fd7ce5SGreg Kroah-Hartman /** 104096fd7ce5SGreg Kroah-Hartman * tty_read - read method for tty device files 104196fd7ce5SGreg Kroah-Hartman * @file: pointer to tty file 104296fd7ce5SGreg Kroah-Hartman * @buf: user buffer 104396fd7ce5SGreg Kroah-Hartman * @count: size of user buffer 104496fd7ce5SGreg Kroah-Hartman * @ppos: unused 104596fd7ce5SGreg Kroah-Hartman * 104696fd7ce5SGreg Kroah-Hartman * Perform the read system call function on this terminal device. Checks 104796fd7ce5SGreg Kroah-Hartman * for hung up devices before calling the line discipline method. 104896fd7ce5SGreg Kroah-Hartman * 104996fd7ce5SGreg Kroah-Hartman * Locking: 105096fd7ce5SGreg Kroah-Hartman * Locks the line discipline internally while needed. Multiple 105196fd7ce5SGreg Kroah-Hartman * read calls may be outstanding in parallel. 105296fd7ce5SGreg Kroah-Hartman */ 105396fd7ce5SGreg Kroah-Hartman 105496fd7ce5SGreg Kroah-Hartman static ssize_t tty_read(struct file *file, char __user *buf, size_t count, 105596fd7ce5SGreg Kroah-Hartman loff_t *ppos) 105696fd7ce5SGreg Kroah-Hartman { 105796fd7ce5SGreg Kroah-Hartman int i; 105837b7f3c7SJiri Slaby struct inode *inode = file_inode(file); 105996fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 106096fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 106196fd7ce5SGreg Kroah-Hartman 106237b7f3c7SJiri Slaby if (tty_paranoia_check(tty, inode, "tty_read")) 106396fd7ce5SGreg Kroah-Hartman return -EIO; 106496fd7ce5SGreg Kroah-Hartman if (!tty || (test_bit(TTY_IO_ERROR, &tty->flags))) 106596fd7ce5SGreg Kroah-Hartman return -EIO; 106696fd7ce5SGreg Kroah-Hartman 106796fd7ce5SGreg Kroah-Hartman /* We want to wait for the line discipline to sort out in this 106896fd7ce5SGreg Kroah-Hartman situation */ 106996fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 107096fd7ce5SGreg Kroah-Hartman if (ld->ops->read) 1071c961bfb1SPeter Hurley i = ld->ops->read(tty, file, buf, count); 107296fd7ce5SGreg Kroah-Hartman else 107396fd7ce5SGreg Kroah-Hartman i = -EIO; 107496fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 1075b0de59b5SJiri Slaby 107637b7f3c7SJiri Slaby if (i > 0) 107737b7f3c7SJiri Slaby tty_update_time(&inode->i_atime); 107837b7f3c7SJiri Slaby 107996fd7ce5SGreg Kroah-Hartman return i; 108096fd7ce5SGreg Kroah-Hartman } 108196fd7ce5SGreg Kroah-Hartman 1082136d5258SPeter Hurley static void tty_write_unlock(struct tty_struct *tty) 108396fd7ce5SGreg Kroah-Hartman { 108496fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty->atomic_write_lock); 108596fd7ce5SGreg Kroah-Hartman wake_up_interruptible_poll(&tty->write_wait, POLLOUT); 108696fd7ce5SGreg Kroah-Hartman } 108796fd7ce5SGreg Kroah-Hartman 1088136d5258SPeter Hurley static int tty_write_lock(struct tty_struct *tty, int ndelay) 108996fd7ce5SGreg Kroah-Hartman { 109096fd7ce5SGreg Kroah-Hartman if (!mutex_trylock(&tty->atomic_write_lock)) { 109196fd7ce5SGreg Kroah-Hartman if (ndelay) 109296fd7ce5SGreg Kroah-Hartman return -EAGAIN; 109396fd7ce5SGreg Kroah-Hartman if (mutex_lock_interruptible(&tty->atomic_write_lock)) 109496fd7ce5SGreg Kroah-Hartman return -ERESTARTSYS; 109596fd7ce5SGreg Kroah-Hartman } 109696fd7ce5SGreg Kroah-Hartman return 0; 109796fd7ce5SGreg Kroah-Hartman } 109896fd7ce5SGreg Kroah-Hartman 109996fd7ce5SGreg Kroah-Hartman /* 110096fd7ce5SGreg Kroah-Hartman * Split writes up in sane blocksizes to avoid 110196fd7ce5SGreg Kroah-Hartman * denial-of-service type attacks 110296fd7ce5SGreg Kroah-Hartman */ 110396fd7ce5SGreg Kroah-Hartman static inline ssize_t do_tty_write( 110496fd7ce5SGreg Kroah-Hartman ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), 110596fd7ce5SGreg Kroah-Hartman struct tty_struct *tty, 110696fd7ce5SGreg Kroah-Hartman struct file *file, 110796fd7ce5SGreg Kroah-Hartman const char __user *buf, 110896fd7ce5SGreg Kroah-Hartman size_t count) 110996fd7ce5SGreg Kroah-Hartman { 111096fd7ce5SGreg Kroah-Hartman ssize_t ret, written = 0; 111196fd7ce5SGreg Kroah-Hartman unsigned int chunk; 111296fd7ce5SGreg Kroah-Hartman 111396fd7ce5SGreg Kroah-Hartman ret = tty_write_lock(tty, file->f_flags & O_NDELAY); 111496fd7ce5SGreg Kroah-Hartman if (ret < 0) 111596fd7ce5SGreg Kroah-Hartman return ret; 111696fd7ce5SGreg Kroah-Hartman 111796fd7ce5SGreg Kroah-Hartman /* 111896fd7ce5SGreg Kroah-Hartman * We chunk up writes into a temporary buffer. This 111996fd7ce5SGreg Kroah-Hartman * simplifies low-level drivers immensely, since they 112096fd7ce5SGreg Kroah-Hartman * don't have locking issues and user mode accesses. 112196fd7ce5SGreg Kroah-Hartman * 112296fd7ce5SGreg Kroah-Hartman * But if TTY_NO_WRITE_SPLIT is set, we should use a 112396fd7ce5SGreg Kroah-Hartman * big chunk-size.. 112496fd7ce5SGreg Kroah-Hartman * 112596fd7ce5SGreg Kroah-Hartman * The default chunk-size is 2kB, because the NTTY 112696fd7ce5SGreg Kroah-Hartman * layer has problems with bigger chunks. It will 112796fd7ce5SGreg Kroah-Hartman * claim to be able to handle more characters than 112896fd7ce5SGreg Kroah-Hartman * it actually does. 112996fd7ce5SGreg Kroah-Hartman * 113096fd7ce5SGreg Kroah-Hartman * FIXME: This can probably go away now except that 64K chunks 113196fd7ce5SGreg Kroah-Hartman * are too likely to fail unless switched to vmalloc... 113296fd7ce5SGreg Kroah-Hartman */ 113396fd7ce5SGreg Kroah-Hartman chunk = 2048; 113496fd7ce5SGreg Kroah-Hartman if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) 113596fd7ce5SGreg Kroah-Hartman chunk = 65536; 113696fd7ce5SGreg Kroah-Hartman if (count < chunk) 113796fd7ce5SGreg Kroah-Hartman chunk = count; 113896fd7ce5SGreg Kroah-Hartman 113996fd7ce5SGreg Kroah-Hartman /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ 114096fd7ce5SGreg Kroah-Hartman if (tty->write_cnt < chunk) { 114196fd7ce5SGreg Kroah-Hartman unsigned char *buf_chunk; 114296fd7ce5SGreg Kroah-Hartman 114396fd7ce5SGreg Kroah-Hartman if (chunk < 1024) 114496fd7ce5SGreg Kroah-Hartman chunk = 1024; 114596fd7ce5SGreg Kroah-Hartman 114696fd7ce5SGreg Kroah-Hartman buf_chunk = kmalloc(chunk, GFP_KERNEL); 114796fd7ce5SGreg Kroah-Hartman if (!buf_chunk) { 114896fd7ce5SGreg Kroah-Hartman ret = -ENOMEM; 114996fd7ce5SGreg Kroah-Hartman goto out; 115096fd7ce5SGreg Kroah-Hartman } 115196fd7ce5SGreg Kroah-Hartman kfree(tty->write_buf); 115296fd7ce5SGreg Kroah-Hartman tty->write_cnt = chunk; 115396fd7ce5SGreg Kroah-Hartman tty->write_buf = buf_chunk; 115496fd7ce5SGreg Kroah-Hartman } 115596fd7ce5SGreg Kroah-Hartman 115696fd7ce5SGreg Kroah-Hartman /* Do the write .. */ 115796fd7ce5SGreg Kroah-Hartman for (;;) { 115896fd7ce5SGreg Kroah-Hartman size_t size = count; 115996fd7ce5SGreg Kroah-Hartman if (size > chunk) 116096fd7ce5SGreg Kroah-Hartman size = chunk; 116196fd7ce5SGreg Kroah-Hartman ret = -EFAULT; 116296fd7ce5SGreg Kroah-Hartman if (copy_from_user(tty->write_buf, buf, size)) 116396fd7ce5SGreg Kroah-Hartman break; 116496fd7ce5SGreg Kroah-Hartman ret = write(tty, file, tty->write_buf, size); 116596fd7ce5SGreg Kroah-Hartman if (ret <= 0) 116696fd7ce5SGreg Kroah-Hartman break; 116796fd7ce5SGreg Kroah-Hartman written += ret; 116896fd7ce5SGreg Kroah-Hartman buf += ret; 116996fd7ce5SGreg Kroah-Hartman count -= ret; 117096fd7ce5SGreg Kroah-Hartman if (!count) 117196fd7ce5SGreg Kroah-Hartman break; 117296fd7ce5SGreg Kroah-Hartman ret = -ERESTARTSYS; 117396fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 117496fd7ce5SGreg Kroah-Hartman break; 117596fd7ce5SGreg Kroah-Hartman cond_resched(); 117696fd7ce5SGreg Kroah-Hartman } 117737b7f3c7SJiri Slaby if (written) { 117837b7f3c7SJiri Slaby tty_update_time(&file_inode(file)->i_mtime); 117996fd7ce5SGreg Kroah-Hartman ret = written; 118037b7f3c7SJiri Slaby } 118196fd7ce5SGreg Kroah-Hartman out: 118296fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 118396fd7ce5SGreg Kroah-Hartman return ret; 118496fd7ce5SGreg Kroah-Hartman } 118596fd7ce5SGreg Kroah-Hartman 118696fd7ce5SGreg Kroah-Hartman /** 118796fd7ce5SGreg Kroah-Hartman * tty_write_message - write a message to a certain tty, not just the console. 118896fd7ce5SGreg Kroah-Hartman * @tty: the destination tty_struct 118996fd7ce5SGreg Kroah-Hartman * @msg: the message to write 119096fd7ce5SGreg Kroah-Hartman * 119196fd7ce5SGreg Kroah-Hartman * This is used for messages that need to be redirected to a specific tty. 119296fd7ce5SGreg Kroah-Hartman * We don't put it into the syslog queue right now maybe in the future if 119396fd7ce5SGreg Kroah-Hartman * really needed. 119496fd7ce5SGreg Kroah-Hartman * 119596fd7ce5SGreg Kroah-Hartman * We must still hold the BTM and test the CLOSING flag for the moment. 119696fd7ce5SGreg Kroah-Hartman */ 119796fd7ce5SGreg Kroah-Hartman 119896fd7ce5SGreg Kroah-Hartman void tty_write_message(struct tty_struct *tty, char *msg) 119996fd7ce5SGreg Kroah-Hartman { 120096fd7ce5SGreg Kroah-Hartman if (tty) { 120196fd7ce5SGreg Kroah-Hartman mutex_lock(&tty->atomic_write_lock); 120289c8d91eSAlan Cox tty_lock(tty); 120304980706SPeter Hurley if (tty->ops->write && tty->count > 0) { 120489c8d91eSAlan Cox tty_unlock(tty); 120596fd7ce5SGreg Kroah-Hartman tty->ops->write(tty, msg, strlen(msg)); 120696fd7ce5SGreg Kroah-Hartman } else 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) 124496fd7ce5SGreg Kroah-Hartman printk(KERN_ERR "tty driver %s lacks a write_room method.\n", 124596fd7ce5SGreg Kroah-Hartman tty->driver->name); 124696fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 124796fd7ce5SGreg Kroah-Hartman if (!ld->ops->write) 124896fd7ce5SGreg Kroah-Hartman ret = -EIO; 124996fd7ce5SGreg Kroah-Hartman else 125096fd7ce5SGreg Kroah-Hartman ret = do_tty_write(ld->ops->write, tty, file, buf, count); 125196fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 125296fd7ce5SGreg Kroah-Hartman return ret; 125396fd7ce5SGreg Kroah-Hartman } 125496fd7ce5SGreg Kroah-Hartman 125596fd7ce5SGreg Kroah-Hartman ssize_t redirected_tty_write(struct file *file, const char __user *buf, 125696fd7ce5SGreg Kroah-Hartman size_t count, loff_t *ppos) 125796fd7ce5SGreg Kroah-Hartman { 125896fd7ce5SGreg Kroah-Hartman struct file *p = NULL; 125996fd7ce5SGreg Kroah-Hartman 126096fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 1261cb0942b8SAl Viro if (redirect) 1262cb0942b8SAl Viro p = get_file(redirect); 126396fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 126496fd7ce5SGreg Kroah-Hartman 126596fd7ce5SGreg Kroah-Hartman if (p) { 126696fd7ce5SGreg Kroah-Hartman ssize_t res; 126796fd7ce5SGreg Kroah-Hartman res = vfs_write(p, buf, count, &p->f_pos); 126896fd7ce5SGreg Kroah-Hartman fput(p); 126996fd7ce5SGreg Kroah-Hartman return res; 127096fd7ce5SGreg Kroah-Hartman } 127196fd7ce5SGreg Kroah-Hartman return tty_write(file, buf, count, ppos); 127296fd7ce5SGreg Kroah-Hartman } 127396fd7ce5SGreg Kroah-Hartman 1274136d5258SPeter Hurley /** 1275136d5258SPeter Hurley * tty_send_xchar - send priority character 1276136d5258SPeter Hurley * 1277136d5258SPeter Hurley * Send a high priority character to the tty even if stopped 1278136d5258SPeter Hurley * 1279136d5258SPeter Hurley * Locking: none for xchar method, write ordering for write method. 1280136d5258SPeter Hurley */ 1281136d5258SPeter Hurley 1282136d5258SPeter Hurley int tty_send_xchar(struct tty_struct *tty, char ch) 1283136d5258SPeter Hurley { 1284136d5258SPeter Hurley int was_stopped = tty->stopped; 1285136d5258SPeter Hurley 1286136d5258SPeter Hurley if (tty->ops->send_xchar) { 1287136d5258SPeter Hurley tty->ops->send_xchar(tty, ch); 1288136d5258SPeter Hurley return 0; 1289136d5258SPeter Hurley } 1290136d5258SPeter Hurley 1291136d5258SPeter Hurley if (tty_write_lock(tty, 0) < 0) 1292136d5258SPeter Hurley return -ERESTARTSYS; 1293136d5258SPeter Hurley 1294136d5258SPeter Hurley if (was_stopped) 1295136d5258SPeter Hurley start_tty(tty); 1296136d5258SPeter Hurley tty->ops->write(tty, &ch, 1); 1297136d5258SPeter Hurley if (was_stopped) 1298136d5258SPeter Hurley stop_tty(tty); 1299136d5258SPeter Hurley tty_write_unlock(tty); 1300136d5258SPeter Hurley return 0; 1301136d5258SPeter Hurley } 1302136d5258SPeter Hurley 130396fd7ce5SGreg Kroah-Hartman static char ptychar[] = "pqrstuvwxyzabcde"; 130496fd7ce5SGreg Kroah-Hartman 130596fd7ce5SGreg Kroah-Hartman /** 130696fd7ce5SGreg Kroah-Hartman * pty_line_name - generate name for a pty 130796fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 130896fd7ce5SGreg Kroah-Hartman * @index: the minor number 130996fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 6 bytes 131096fd7ce5SGreg Kroah-Hartman * 131196fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 131296fd7ce5SGreg Kroah-Hartman * buffer. 131396fd7ce5SGreg Kroah-Hartman * 131496fd7ce5SGreg Kroah-Hartman * Locking: None 131596fd7ce5SGreg Kroah-Hartman */ 131696fd7ce5SGreg Kroah-Hartman static void pty_line_name(struct tty_driver *driver, int index, char *p) 131796fd7ce5SGreg Kroah-Hartman { 131896fd7ce5SGreg Kroah-Hartman int i = index + driver->name_base; 131996fd7ce5SGreg Kroah-Hartman /* ->name is initialized to "ttyp", but "tty" is expected */ 132096fd7ce5SGreg Kroah-Hartman sprintf(p, "%s%c%x", 132196fd7ce5SGreg Kroah-Hartman driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, 132296fd7ce5SGreg Kroah-Hartman ptychar[i >> 4 & 0xf], i & 0xf); 132396fd7ce5SGreg Kroah-Hartman } 132496fd7ce5SGreg Kroah-Hartman 132596fd7ce5SGreg Kroah-Hartman /** 132696fd7ce5SGreg Kroah-Hartman * tty_line_name - generate name for a tty 132796fd7ce5SGreg Kroah-Hartman * @driver: the tty driver in use 132896fd7ce5SGreg Kroah-Hartman * @index: the minor number 132996fd7ce5SGreg Kroah-Hartman * @p: output buffer of at least 7 bytes 133096fd7ce5SGreg Kroah-Hartman * 133196fd7ce5SGreg Kroah-Hartman * Generate a name from a driver reference and write it to the output 13325c0a2450SGreg Kroah-Hartman * buffer. 133396fd7ce5SGreg Kroah-Hartman * 133496fd7ce5SGreg Kroah-Hartman * Locking: None 133596fd7ce5SGreg Kroah-Hartman */ 1336723abd87SHannes Reinecke static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p) 133796fd7ce5SGreg Kroah-Hartman { 13380019b408SJiri Slaby if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE) 1339723abd87SHannes Reinecke return sprintf(p, "%s", driver->name); 13400019b408SJiri Slaby else 1341723abd87SHannes Reinecke return sprintf(p, "%s%d", driver->name, 1342723abd87SHannes Reinecke index + driver->name_base); 134396fd7ce5SGreg Kroah-Hartman } 134496fd7ce5SGreg Kroah-Hartman 134596fd7ce5SGreg Kroah-Hartman /** 134696fd7ce5SGreg Kroah-Hartman * tty_driver_lookup_tty() - find an existing tty, if any 134796fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 134896fd7ce5SGreg Kroah-Hartman * @idx: the minor number 134996fd7ce5SGreg Kroah-Hartman * 1350aa3cb814SPeter Hurley * Return the tty, if found. If not found, return NULL or ERR_PTR() if the 1351aa3cb814SPeter Hurley * driver lookup() method returns an error. 135296fd7ce5SGreg Kroah-Hartman * 1353aa3cb814SPeter Hurley * Locking: tty_mutex must be held. If the tty is found, bump the tty kref. 135496fd7ce5SGreg Kroah-Hartman */ 135596fd7ce5SGreg Kroah-Hartman static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, 135696fd7ce5SGreg Kroah-Hartman struct inode *inode, int idx) 135796fd7ce5SGreg Kroah-Hartman { 1358aa3cb814SPeter Hurley struct tty_struct *tty; 135996fd7ce5SGreg Kroah-Hartman 1360aa3cb814SPeter Hurley if (driver->ops->lookup) 1361aa3cb814SPeter Hurley tty = driver->ops->lookup(driver, inode, idx); 1362aa3cb814SPeter Hurley else 1363aa3cb814SPeter Hurley tty = driver->ttys[idx]; 1364aa3cb814SPeter Hurley 1365aa3cb814SPeter Hurley if (!IS_ERR(tty)) 1366aa3cb814SPeter Hurley tty_kref_get(tty); 1367aa3cb814SPeter Hurley return tty; 136896fd7ce5SGreg Kroah-Hartman } 136996fd7ce5SGreg Kroah-Hartman 137096fd7ce5SGreg Kroah-Hartman /** 137196fd7ce5SGreg Kroah-Hartman * tty_init_termios - helper for termios setup 137296fd7ce5SGreg Kroah-Hartman * @tty: the tty to set up 137396fd7ce5SGreg Kroah-Hartman * 137496fd7ce5SGreg Kroah-Hartman * Initialise the termios structures for this tty. Thus runs under 137596fd7ce5SGreg Kroah-Hartman * the tty_mutex currently so we can be relaxed about ordering. 137696fd7ce5SGreg Kroah-Hartman */ 137796fd7ce5SGreg Kroah-Hartman 137896fd7ce5SGreg Kroah-Hartman int tty_init_termios(struct tty_struct *tty) 137996fd7ce5SGreg Kroah-Hartman { 138096fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 138196fd7ce5SGreg Kroah-Hartman int idx = tty->index; 138296fd7ce5SGreg Kroah-Hartman 138336b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 138436b3c070SAlan Cox tty->termios = tty->driver->init_termios; 138536b3c070SAlan Cox else { 138636b3c070SAlan Cox /* Check for lazy saved data */ 138796fd7ce5SGreg Kroah-Hartman tp = tty->driver->termios[idx]; 138836b3c070SAlan Cox if (tp != NULL) 1389adc8d746SAlan Cox tty->termios = *tp; 139036b3c070SAlan Cox else 139136b3c070SAlan Cox tty->termios = tty->driver->init_termios; 139236b3c070SAlan Cox } 139396fd7ce5SGreg Kroah-Hartman /* Compatibility until drivers always set this */ 1394adc8d746SAlan Cox tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios); 1395adc8d746SAlan Cox tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios); 139696fd7ce5SGreg Kroah-Hartman return 0; 139796fd7ce5SGreg Kroah-Hartman } 139896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_init_termios); 139996fd7ce5SGreg Kroah-Hartman 140066d450e8SJiri Slaby int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty) 140166d450e8SJiri Slaby { 140266d450e8SJiri Slaby int ret = tty_init_termios(tty); 140366d450e8SJiri Slaby if (ret) 140466d450e8SJiri Slaby return ret; 140566d450e8SJiri Slaby 140666d450e8SJiri Slaby tty_driver_kref_get(driver); 140766d450e8SJiri Slaby tty->count++; 140866d450e8SJiri Slaby driver->ttys[tty->index] = tty; 140966d450e8SJiri Slaby return 0; 141066d450e8SJiri Slaby } 141166d450e8SJiri Slaby EXPORT_SYMBOL_GPL(tty_standard_install); 141266d450e8SJiri Slaby 141396fd7ce5SGreg Kroah-Hartman /** 141496fd7ce5SGreg Kroah-Hartman * tty_driver_install_tty() - install a tty entry in the driver 141596fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 141696fd7ce5SGreg Kroah-Hartman * @tty: the tty 141796fd7ce5SGreg Kroah-Hartman * 141896fd7ce5SGreg Kroah-Hartman * Install a tty object into the driver tables. The tty->index field 141996fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. This method is responsible 142096fd7ce5SGreg Kroah-Hartman * for ensuring any need additional structures are allocated and 142196fd7ce5SGreg Kroah-Hartman * configured. 142296fd7ce5SGreg Kroah-Hartman * 142396fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 142496fd7ce5SGreg Kroah-Hartman */ 142596fd7ce5SGreg Kroah-Hartman static int tty_driver_install_tty(struct tty_driver *driver, 142696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty) 142796fd7ce5SGreg Kroah-Hartman { 142866d450e8SJiri Slaby return driver->ops->install ? driver->ops->install(driver, tty) : 142966d450e8SJiri Slaby tty_standard_install(driver, tty); 143096fd7ce5SGreg Kroah-Hartman } 143196fd7ce5SGreg Kroah-Hartman 143296fd7ce5SGreg Kroah-Hartman /** 143396fd7ce5SGreg Kroah-Hartman * tty_driver_remove_tty() - remove a tty from the driver tables 143496fd7ce5SGreg Kroah-Hartman * @driver: the driver for the tty 143596fd7ce5SGreg Kroah-Hartman * @idx: the minor number 143696fd7ce5SGreg Kroah-Hartman * 143796fd7ce5SGreg Kroah-Hartman * Remvoe a tty object from the driver tables. The tty->index field 143896fd7ce5SGreg Kroah-Hartman * will be set by the time this is called. 143996fd7ce5SGreg Kroah-Hartman * 144096fd7ce5SGreg Kroah-Hartman * Locking: tty_mutex for now 144196fd7ce5SGreg Kroah-Hartman */ 144224d406a6SJiri Slaby void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty) 144396fd7ce5SGreg Kroah-Hartman { 144496fd7ce5SGreg Kroah-Hartman if (driver->ops->remove) 144596fd7ce5SGreg Kroah-Hartman driver->ops->remove(driver, tty); 144696fd7ce5SGreg Kroah-Hartman else 144796fd7ce5SGreg Kroah-Hartman driver->ttys[tty->index] = NULL; 144896fd7ce5SGreg Kroah-Hartman } 144996fd7ce5SGreg Kroah-Hartman 145096fd7ce5SGreg Kroah-Hartman /* 145196fd7ce5SGreg Kroah-Hartman * tty_reopen() - fast re-open of an open tty 145296fd7ce5SGreg Kroah-Hartman * @tty - the tty to open 145396fd7ce5SGreg Kroah-Hartman * 145496fd7ce5SGreg Kroah-Hartman * Return 0 on success, -errno on error. 14555d93e748SPeter Hurley * Re-opens on master ptys are not allowed and return -EIO. 145696fd7ce5SGreg Kroah-Hartman * 14575d93e748SPeter Hurley * Locking: Caller must hold tty_lock 145896fd7ce5SGreg Kroah-Hartman */ 145996fd7ce5SGreg Kroah-Hartman static int tty_reopen(struct tty_struct *tty) 146096fd7ce5SGreg Kroah-Hartman { 146196fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 146296fd7ce5SGreg Kroah-Hartman 1463216030ecSPeter Hurley if (!tty->count) 146496fd7ce5SGreg Kroah-Hartman return -EIO; 146596fd7ce5SGreg Kroah-Hartman 146696fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY && 14675d93e748SPeter Hurley driver->subtype == PTY_TYPE_MASTER) 146896fd7ce5SGreg Kroah-Hartman return -EIO; 146996fd7ce5SGreg Kroah-Hartman 147086f2c00fSPeter Hurley if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN)) 147186f2c00fSPeter Hurley return -EBUSY; 147286f2c00fSPeter Hurley 147396fd7ce5SGreg Kroah-Hartman tty->count++; 147496fd7ce5SGreg Kroah-Hartman 147536697529SPeter Hurley WARN_ON(!tty->ldisc); 147696fd7ce5SGreg Kroah-Hartman 147796fd7ce5SGreg Kroah-Hartman return 0; 147896fd7ce5SGreg Kroah-Hartman } 147996fd7ce5SGreg Kroah-Hartman 148096fd7ce5SGreg Kroah-Hartman /** 148196fd7ce5SGreg Kroah-Hartman * tty_init_dev - initialise a tty device 148296fd7ce5SGreg Kroah-Hartman * @driver: tty driver we are opening a device on 148396fd7ce5SGreg Kroah-Hartman * @idx: device index 148496fd7ce5SGreg Kroah-Hartman * @ret_tty: returned tty structure 148596fd7ce5SGreg Kroah-Hartman * 148696fd7ce5SGreg Kroah-Hartman * Prepare a tty device. This may not be a "new" clean device but 148796fd7ce5SGreg Kroah-Hartman * could also be an active device. The pty drivers require special 148896fd7ce5SGreg Kroah-Hartman * handling because of this. 148996fd7ce5SGreg Kroah-Hartman * 149096fd7ce5SGreg Kroah-Hartman * Locking: 149196fd7ce5SGreg Kroah-Hartman * The function is called under the tty_mutex, which 149296fd7ce5SGreg Kroah-Hartman * protects us from the tty struct or driver itself going away. 149396fd7ce5SGreg Kroah-Hartman * 149496fd7ce5SGreg Kroah-Hartman * On exit the tty device has the line discipline attached and 149596fd7ce5SGreg Kroah-Hartman * a reference count of 1. If a pair was created for pty/tty use 149696fd7ce5SGreg Kroah-Hartman * and the other was a pty master then it too has a reference count of 1. 149796fd7ce5SGreg Kroah-Hartman * 149896fd7ce5SGreg Kroah-Hartman * WSH 06/09/97: Rewritten to remove races and properly clean up after a 149996fd7ce5SGreg Kroah-Hartman * failed open. The new code protects the open with a mutex, so it's 150096fd7ce5SGreg Kroah-Hartman * really quite straightforward. The mutex locking can probably be 150196fd7ce5SGreg Kroah-Hartman * relaxed for the (most common) case of reopening a tty. 150296fd7ce5SGreg Kroah-Hartman */ 150396fd7ce5SGreg Kroah-Hartman 1504593a27c4SKonstantin Khlebnikov struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) 150596fd7ce5SGreg Kroah-Hartman { 150696fd7ce5SGreg Kroah-Hartman struct tty_struct *tty; 150796fd7ce5SGreg Kroah-Hartman int retval; 150896fd7ce5SGreg Kroah-Hartman 150996fd7ce5SGreg Kroah-Hartman /* 151096fd7ce5SGreg Kroah-Hartman * First time open is complex, especially for PTY devices. 151196fd7ce5SGreg Kroah-Hartman * This code guarantees that either everything succeeds and the 151296fd7ce5SGreg Kroah-Hartman * TTY is ready for operation, or else the table slots are vacated 151396fd7ce5SGreg Kroah-Hartman * and the allocated memory released. (Except that the termios 151496fd7ce5SGreg Kroah-Hartman * and locked termios may be retained.) 151596fd7ce5SGreg Kroah-Hartman */ 151696fd7ce5SGreg Kroah-Hartman 151796fd7ce5SGreg Kroah-Hartman if (!try_module_get(driver->owner)) 151896fd7ce5SGreg Kroah-Hartman return ERR_PTR(-ENODEV); 151996fd7ce5SGreg Kroah-Hartman 15202c964a2fSRasmus Villemoes tty = alloc_tty_struct(driver, idx); 1521d5543503SJiri Slaby if (!tty) { 1522d5543503SJiri Slaby retval = -ENOMEM; 1523d5543503SJiri Slaby goto err_module_put; 1524d5543503SJiri Slaby } 152596fd7ce5SGreg Kroah-Hartman 152689c8d91eSAlan Cox tty_lock(tty); 152796fd7ce5SGreg Kroah-Hartman retval = tty_driver_install_tty(driver, tty); 1528d5543503SJiri Slaby if (retval < 0) 1529a9dccddbSJiri Slaby goto err_deinit_tty; 153096fd7ce5SGreg Kroah-Hartman 153104831dc1SJiri Slaby if (!tty->port) 153204831dc1SJiri Slaby tty->port = driver->ports[idx]; 153304831dc1SJiri Slaby 15345d4121c0SJiri Slaby WARN_RATELIMIT(!tty->port, 15355d4121c0SJiri Slaby "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", 15365d4121c0SJiri Slaby __func__, tty->driver->name); 15375d4121c0SJiri Slaby 1538967fab69SJiri Slaby tty->port->itty = tty; 1539967fab69SJiri Slaby 154096fd7ce5SGreg Kroah-Hartman /* 154196fd7ce5SGreg Kroah-Hartman * Structures all installed ... call the ldisc open routines. 154296fd7ce5SGreg Kroah-Hartman * If we fail here just call release_tty to clean up. No need 154396fd7ce5SGreg Kroah-Hartman * to decrement the use counts, as release_tty doesn't care. 154496fd7ce5SGreg Kroah-Hartman */ 154596fd7ce5SGreg Kroah-Hartman retval = tty_ldisc_setup(tty, tty->link); 154696fd7ce5SGreg Kroah-Hartman if (retval) 1547d5543503SJiri Slaby goto err_release_tty; 154889c8d91eSAlan Cox /* Return the tty locked so that it cannot vanish under the caller */ 154996fd7ce5SGreg Kroah-Hartman return tty; 155096fd7ce5SGreg Kroah-Hartman 1551a9dccddbSJiri Slaby err_deinit_tty: 155289c8d91eSAlan Cox tty_unlock(tty); 1553a9dccddbSJiri Slaby deinitialize_tty_struct(tty); 1554d5543503SJiri Slaby free_tty_struct(tty); 1555d5543503SJiri Slaby err_module_put: 155696fd7ce5SGreg Kroah-Hartman module_put(driver->owner); 1557d5543503SJiri Slaby return ERR_PTR(retval); 155896fd7ce5SGreg Kroah-Hartman 155996fd7ce5SGreg Kroah-Hartman /* call the tty release_tty routine to clean out this slot */ 1560d5543503SJiri Slaby err_release_tty: 156189c8d91eSAlan Cox tty_unlock(tty); 15625a3c6b25SManuel Zerpies printk_ratelimited(KERN_INFO "tty_init_dev: ldisc open failed, " 156396fd7ce5SGreg Kroah-Hartman "clearing slot %d\n", idx); 156496fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 156596fd7ce5SGreg Kroah-Hartman return ERR_PTR(retval); 156696fd7ce5SGreg Kroah-Hartman } 156796fd7ce5SGreg Kroah-Hartman 156896fd7ce5SGreg Kroah-Hartman void tty_free_termios(struct tty_struct *tty) 156996fd7ce5SGreg Kroah-Hartman { 157096fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 157196fd7ce5SGreg Kroah-Hartman int idx = tty->index; 157236b3c070SAlan Cox 157336b3c070SAlan Cox /* If the port is going to reset then it has no termios to save */ 157436b3c070SAlan Cox if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) 157536b3c070SAlan Cox return; 157636b3c070SAlan Cox 157736b3c070SAlan Cox /* Stash the termios data */ 1578adc8d746SAlan Cox tp = tty->driver->termios[idx]; 157936b3c070SAlan Cox if (tp == NULL) { 158036b3c070SAlan Cox tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL); 158136b3c070SAlan Cox if (tp == NULL) { 158236b3c070SAlan Cox pr_warn("tty: no memory to save termios state.\n"); 158336b3c070SAlan Cox return; 158496fd7ce5SGreg Kroah-Hartman } 15854ac5d705SDan Carpenter tty->driver->termios[idx] = tp; 158636b3c070SAlan Cox } 158736b3c070SAlan Cox *tp = tty->termios; 158896fd7ce5SGreg Kroah-Hartman } 158996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_free_termios); 159096fd7ce5SGreg Kroah-Hartman 1591a2965b7bSPeter Hurley /** 1592949aa64fSPeter Hurley * tty_flush_works - flush all works of a tty/pty pair 1593949aa64fSPeter Hurley * @tty: tty device to flush works for (or either end of a pty pair) 1594a2965b7bSPeter Hurley * 1595949aa64fSPeter Hurley * Sync flush all works belonging to @tty (and the 'other' tty). 1596a2965b7bSPeter Hurley */ 1597a2965b7bSPeter Hurley static void tty_flush_works(struct tty_struct *tty) 1598a2965b7bSPeter Hurley { 1599a2965b7bSPeter Hurley flush_work(&tty->SAK_work); 1600a2965b7bSPeter Hurley flush_work(&tty->hangup_work); 1601949aa64fSPeter Hurley if (tty->link) { 1602949aa64fSPeter Hurley flush_work(&tty->link->SAK_work); 1603949aa64fSPeter Hurley flush_work(&tty->link->hangup_work); 1604949aa64fSPeter Hurley } 1605a2965b7bSPeter Hurley } 160696fd7ce5SGreg Kroah-Hartman 160796fd7ce5SGreg Kroah-Hartman /** 160896fd7ce5SGreg Kroah-Hartman * release_one_tty - release tty structure memory 160996fd7ce5SGreg Kroah-Hartman * @kref: kref of tty we are obliterating 161096fd7ce5SGreg Kroah-Hartman * 161196fd7ce5SGreg Kroah-Hartman * Releases memory associated with a tty structure, and clears out the 161296fd7ce5SGreg Kroah-Hartman * driver table slots. This function is called when a device is no longer 161396fd7ce5SGreg Kroah-Hartman * in use. It also gets called when setup of a device fails. 161496fd7ce5SGreg Kroah-Hartman * 161596fd7ce5SGreg Kroah-Hartman * Locking: 161696fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 161796fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 161896fd7ce5SGreg Kroah-Hartman * 161996fd7ce5SGreg Kroah-Hartman * This method gets called from a work queue so that the driver private 162096fd7ce5SGreg Kroah-Hartman * cleanup ops can sleep (needed for USB at least) 162196fd7ce5SGreg Kroah-Hartman */ 162296fd7ce5SGreg Kroah-Hartman static void release_one_tty(struct work_struct *work) 162396fd7ce5SGreg Kroah-Hartman { 162496fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 162596fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, hangup_work); 162696fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = tty->driver; 1627b216df53SCyrill Gorcunov struct module *owner = driver->owner; 162896fd7ce5SGreg Kroah-Hartman 162996fd7ce5SGreg Kroah-Hartman if (tty->ops->cleanup) 163096fd7ce5SGreg Kroah-Hartman tty->ops->cleanup(tty); 163196fd7ce5SGreg Kroah-Hartman 163296fd7ce5SGreg Kroah-Hartman tty->magic = 0; 163396fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(driver); 1634b216df53SCyrill Gorcunov module_put(owner); 163596fd7ce5SGreg Kroah-Hartman 163696fd7ce5SGreg Kroah-Hartman spin_lock(&tty_files_lock); 163796fd7ce5SGreg Kroah-Hartman list_del_init(&tty->tty_files); 163896fd7ce5SGreg Kroah-Hartman spin_unlock(&tty_files_lock); 163996fd7ce5SGreg Kroah-Hartman 164096fd7ce5SGreg Kroah-Hartman put_pid(tty->pgrp); 164196fd7ce5SGreg Kroah-Hartman put_pid(tty->session); 164296fd7ce5SGreg Kroah-Hartman free_tty_struct(tty); 164396fd7ce5SGreg Kroah-Hartman } 164496fd7ce5SGreg Kroah-Hartman 164596fd7ce5SGreg Kroah-Hartman static void queue_release_one_tty(struct kref *kref) 164696fd7ce5SGreg Kroah-Hartman { 164796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = container_of(kref, struct tty_struct, kref); 164896fd7ce5SGreg Kroah-Hartman 164996fd7ce5SGreg Kroah-Hartman /* The hangup queue is now free so we can reuse it rather than 165096fd7ce5SGreg Kroah-Hartman waste a chunk of memory for each port */ 165196fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, release_one_tty); 165296fd7ce5SGreg Kroah-Hartman schedule_work(&tty->hangup_work); 165396fd7ce5SGreg Kroah-Hartman } 165496fd7ce5SGreg Kroah-Hartman 165596fd7ce5SGreg Kroah-Hartman /** 165696fd7ce5SGreg Kroah-Hartman * tty_kref_put - release a tty kref 165796fd7ce5SGreg Kroah-Hartman * @tty: tty device 165896fd7ce5SGreg Kroah-Hartman * 165996fd7ce5SGreg Kroah-Hartman * Release a reference to a tty device and if need be let the kref 166096fd7ce5SGreg Kroah-Hartman * layer destruct the object for us 166196fd7ce5SGreg Kroah-Hartman */ 166296fd7ce5SGreg Kroah-Hartman 166396fd7ce5SGreg Kroah-Hartman void tty_kref_put(struct tty_struct *tty) 166496fd7ce5SGreg Kroah-Hartman { 166596fd7ce5SGreg Kroah-Hartman if (tty) 166696fd7ce5SGreg Kroah-Hartman kref_put(&tty->kref, queue_release_one_tty); 166796fd7ce5SGreg Kroah-Hartman } 166896fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_kref_put); 166996fd7ce5SGreg Kroah-Hartman 167096fd7ce5SGreg Kroah-Hartman /** 167196fd7ce5SGreg Kroah-Hartman * release_tty - release tty structure memory 167296fd7ce5SGreg Kroah-Hartman * 167396fd7ce5SGreg Kroah-Hartman * Release both @tty and a possible linked partner (think pty pair), 167496fd7ce5SGreg Kroah-Hartman * and decrement the refcount of the backing module. 167596fd7ce5SGreg Kroah-Hartman * 167696fd7ce5SGreg Kroah-Hartman * Locking: 1677d155255aSAlan Cox * tty_mutex 167896fd7ce5SGreg Kroah-Hartman * takes the file list lock internally when working on the list 167996fd7ce5SGreg Kroah-Hartman * of ttys that the driver keeps. 168096fd7ce5SGreg Kroah-Hartman * 168196fd7ce5SGreg Kroah-Hartman */ 168296fd7ce5SGreg Kroah-Hartman static void release_tty(struct tty_struct *tty, int idx) 168396fd7ce5SGreg Kroah-Hartman { 168496fd7ce5SGreg Kroah-Hartman /* This should always be true but check for the moment */ 168596fd7ce5SGreg Kroah-Hartman WARN_ON(tty->index != idx); 1686d155255aSAlan Cox WARN_ON(!mutex_is_locked(&tty_mutex)); 168736b3c070SAlan Cox if (tty->ops->shutdown) 168836b3c070SAlan Cox tty->ops->shutdown(tty); 168936b3c070SAlan Cox tty_free_termios(tty); 169036b3c070SAlan Cox tty_driver_remove_tty(tty->driver, tty); 1691967fab69SJiri Slaby tty->port->itty = NULL; 169264e377dcSPeter Hurley if (tty->link) 169364e377dcSPeter Hurley tty->link->port->itty = NULL; 16944f98d467SPeter Hurley cancel_work_sync(&tty->port->buf.work); 169536b3c070SAlan Cox 169696fd7ce5SGreg Kroah-Hartman tty_kref_put(tty->link); 169796fd7ce5SGreg Kroah-Hartman tty_kref_put(tty); 169896fd7ce5SGreg Kroah-Hartman } 169996fd7ce5SGreg Kroah-Hartman 170096fd7ce5SGreg Kroah-Hartman /** 1701955787caSJiri Slaby * tty_release_checks - check a tty before real release 1702955787caSJiri Slaby * @tty: tty to check 1703955787caSJiri Slaby * @o_tty: link of @tty (if any) 1704955787caSJiri Slaby * @idx: index of the tty 1705955787caSJiri Slaby * 1706955787caSJiri Slaby * Performs some paranoid checking before true release of the @tty. 1707955787caSJiri Slaby * This is a no-op unless TTY_PARANOIA_CHECK is defined. 1708955787caSJiri Slaby */ 1709359b9fb5SPeter Hurley static int tty_release_checks(struct tty_struct *tty, int idx) 1710955787caSJiri Slaby { 1711955787caSJiri Slaby #ifdef TTY_PARANOIA_CHECK 1712955787caSJiri Slaby if (idx < 0 || idx >= tty->driver->num) { 1713e2dfa3d3SPeter Hurley tty_debug(tty, "bad idx %d\n", idx); 1714955787caSJiri Slaby return -1; 1715955787caSJiri Slaby } 1716955787caSJiri Slaby 1717955787caSJiri Slaby /* not much to check for devpts */ 1718955787caSJiri Slaby if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) 1719955787caSJiri Slaby return 0; 1720955787caSJiri Slaby 1721955787caSJiri Slaby if (tty != tty->driver->ttys[idx]) { 1722e2dfa3d3SPeter Hurley tty_debug(tty, "bad driver table[%d] = %p\n", 1723e2dfa3d3SPeter Hurley idx, tty->driver->ttys[idx]); 1724955787caSJiri Slaby return -1; 1725955787caSJiri Slaby } 1726955787caSJiri Slaby if (tty->driver->other) { 1727359b9fb5SPeter Hurley struct tty_struct *o_tty = tty->link; 1728359b9fb5SPeter Hurley 1729955787caSJiri Slaby if (o_tty != tty->driver->other->ttys[idx]) { 1730e2dfa3d3SPeter Hurley tty_debug(tty, "bad other table[%d] = %p\n", 1731e2dfa3d3SPeter Hurley idx, tty->driver->other->ttys[idx]); 1732955787caSJiri Slaby return -1; 1733955787caSJiri Slaby } 1734955787caSJiri Slaby if (o_tty->link != tty) { 1735e2dfa3d3SPeter Hurley tty_debug(tty, "bad link = %p\n", o_tty->link); 1736955787caSJiri Slaby return -1; 1737955787caSJiri Slaby } 1738955787caSJiri Slaby } 1739955787caSJiri Slaby #endif 1740955787caSJiri Slaby return 0; 1741955787caSJiri Slaby } 1742955787caSJiri Slaby 1743955787caSJiri Slaby /** 174496fd7ce5SGreg Kroah-Hartman * tty_release - vfs callback for close 174596fd7ce5SGreg Kroah-Hartman * @inode: inode of tty 174696fd7ce5SGreg Kroah-Hartman * @filp: file pointer for handle to tty 174796fd7ce5SGreg Kroah-Hartman * 174896fd7ce5SGreg Kroah-Hartman * Called the last time each file handle is closed that references 174996fd7ce5SGreg Kroah-Hartman * this tty. There may however be several such references. 175096fd7ce5SGreg Kroah-Hartman * 175196fd7ce5SGreg Kroah-Hartman * Locking: 175296fd7ce5SGreg Kroah-Hartman * Takes bkl. See tty_release_dev 175396fd7ce5SGreg Kroah-Hartman * 175496fd7ce5SGreg Kroah-Hartman * Even releasing the tty structures is a tricky business.. We have 175596fd7ce5SGreg Kroah-Hartman * to be very careful that the structures are all released at the 175696fd7ce5SGreg Kroah-Hartman * same time, as interrupts might otherwise get the wrong pointers. 175796fd7ce5SGreg Kroah-Hartman * 175896fd7ce5SGreg Kroah-Hartman * WSH 09/09/97: rewritten to avoid some nasty race conditions that could 175996fd7ce5SGreg Kroah-Hartman * lead to double frees or releasing memory still in use. 176096fd7ce5SGreg Kroah-Hartman */ 176196fd7ce5SGreg Kroah-Hartman 176296fd7ce5SGreg Kroah-Hartman int tty_release(struct inode *inode, struct file *filp) 176396fd7ce5SGreg Kroah-Hartman { 176496fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 17657ffb6da9SPeter Hurley struct tty_struct *o_tty = NULL; 17667ffb6da9SPeter Hurley int do_sleep, final; 176796fd7ce5SGreg Kroah-Hartman int idx; 176837b16457SPeter Hurley long timeout = 0; 1769494c1eacSPeter Hurley int once = 1; 177096fd7ce5SGreg Kroah-Hartman 17719de44bd6SJiri Slaby if (tty_paranoia_check(tty, inode, __func__)) 177296fd7ce5SGreg Kroah-Hartman return 0; 177396fd7ce5SGreg Kroah-Hartman 177489c8d91eSAlan Cox tty_lock(tty); 17759de44bd6SJiri Slaby check_tty_count(tty, __func__); 177696fd7ce5SGreg Kroah-Hartman 177796fd7ce5SGreg Kroah-Hartman __tty_fasync(-1, filp, 0); 177896fd7ce5SGreg Kroah-Hartman 177996fd7ce5SGreg Kroah-Hartman idx = tty->index; 17807ffb6da9SPeter Hurley if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 17817ffb6da9SPeter Hurley tty->driver->subtype == PTY_TYPE_MASTER) 178296fd7ce5SGreg Kroah-Hartman o_tty = tty->link; 178396fd7ce5SGreg Kroah-Hartman 1784359b9fb5SPeter Hurley if (tty_release_checks(tty, idx)) { 178589c8d91eSAlan Cox tty_unlock(tty); 178696fd7ce5SGreg Kroah-Hartman return 0; 178796fd7ce5SGreg Kroah-Hartman } 178896fd7ce5SGreg Kroah-Hartman 1789accff793SPeter Hurley tty_debug_hangup(tty, "(tty count=%d)...\n", tty->count); 179096fd7ce5SGreg Kroah-Hartman 179196fd7ce5SGreg Kroah-Hartman if (tty->ops->close) 179296fd7ce5SGreg Kroah-Hartman tty->ops->close(tty, filp); 179396fd7ce5SGreg Kroah-Hartman 17942aff5e2bSPeter Hurley /* If tty is pty master, lock the slave pty (stable lock order) */ 17952aff5e2bSPeter Hurley tty_lock_slave(o_tty); 17962aff5e2bSPeter Hurley 179796fd7ce5SGreg Kroah-Hartman /* 179896fd7ce5SGreg Kroah-Hartman * Sanity check: if tty->count is going to zero, there shouldn't be 179996fd7ce5SGreg Kroah-Hartman * any waiters on tty->read_wait or tty->write_wait. We test the 180096fd7ce5SGreg Kroah-Hartman * wait queues and kick everyone out _before_ actually starting to 180196fd7ce5SGreg Kroah-Hartman * close. This ensures that we won't block while releasing the tty 180296fd7ce5SGreg Kroah-Hartman * structure. 180396fd7ce5SGreg Kroah-Hartman * 180496fd7ce5SGreg Kroah-Hartman * The test for the o_tty closing is necessary, since the master and 180596fd7ce5SGreg Kroah-Hartman * slave sides may close in any order. If the slave side closes out 180696fd7ce5SGreg Kroah-Hartman * first, its count will be one, since the master side holds an open. 1807324c1650SPeter Hurley * Thus this test wouldn't be triggered at the time the slave closed, 180896fd7ce5SGreg Kroah-Hartman * so we do it now. 180996fd7ce5SGreg Kroah-Hartman */ 1810d5e370a4SPeter Hurley while (1) { 181196fd7ce5SGreg Kroah-Hartman do_sleep = 0; 181296fd7ce5SGreg Kroah-Hartman 1813324c1650SPeter Hurley if (tty->count <= 1) { 181496fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->read_wait)) { 181596fd7ce5SGreg Kroah-Hartman wake_up_poll(&tty->read_wait, POLLIN); 181696fd7ce5SGreg Kroah-Hartman do_sleep++; 181796fd7ce5SGreg Kroah-Hartman } 181896fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&tty->write_wait)) { 181996fd7ce5SGreg Kroah-Hartman wake_up_poll(&tty->write_wait, POLLOUT); 182096fd7ce5SGreg Kroah-Hartman do_sleep++; 182196fd7ce5SGreg Kroah-Hartman } 182296fd7ce5SGreg Kroah-Hartman } 18237ffb6da9SPeter Hurley if (o_tty && o_tty->count <= 1) { 182496fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->read_wait)) { 182596fd7ce5SGreg Kroah-Hartman wake_up_poll(&o_tty->read_wait, POLLIN); 182696fd7ce5SGreg Kroah-Hartman do_sleep++; 182796fd7ce5SGreg Kroah-Hartman } 182896fd7ce5SGreg Kroah-Hartman if (waitqueue_active(&o_tty->write_wait)) { 182996fd7ce5SGreg Kroah-Hartman wake_up_poll(&o_tty->write_wait, POLLOUT); 183096fd7ce5SGreg Kroah-Hartman do_sleep++; 183196fd7ce5SGreg Kroah-Hartman } 183296fd7ce5SGreg Kroah-Hartman } 183396fd7ce5SGreg Kroah-Hartman if (!do_sleep) 183496fd7ce5SGreg Kroah-Hartman break; 183596fd7ce5SGreg Kroah-Hartman 1836494c1eacSPeter Hurley if (once) { 1837494c1eacSPeter Hurley once = 0; 18389de44bd6SJiri Slaby printk(KERN_WARNING "%s: %s: read/write wait queue active!\n", 1839429b4749SRasmus Villemoes __func__, tty_name(tty)); 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) { 18509de44bd6SJiri Slaby printk(KERN_WARNING "%s: bad pty slave count (%d) for %s\n", 1851429b4749SRasmus Villemoes __func__, o_tty->count, tty_name(o_tty)); 185296fd7ce5SGreg Kroah-Hartman o_tty->count = 0; 185396fd7ce5SGreg Kroah-Hartman } 185496fd7ce5SGreg Kroah-Hartman } 185596fd7ce5SGreg Kroah-Hartman if (--tty->count < 0) { 18569de44bd6SJiri Slaby printk(KERN_WARNING "%s: bad tty->count (%d) for %s\n", 1857429b4749SRasmus Villemoes __func__, tty->count, tty_name(tty)); 185896fd7ce5SGreg Kroah-Hartman tty->count = 0; 185996fd7ce5SGreg Kroah-Hartman } 186096fd7ce5SGreg Kroah-Hartman 186196fd7ce5SGreg Kroah-Hartman /* 186296fd7ce5SGreg Kroah-Hartman * We've decremented tty->count, so we need to remove this file 186396fd7ce5SGreg Kroah-Hartman * descriptor off the tty->tty_files list; this serves two 186496fd7ce5SGreg Kroah-Hartman * purposes: 186596fd7ce5SGreg Kroah-Hartman * - check_tty_count sees the correct number of file descriptors 186696fd7ce5SGreg Kroah-Hartman * associated with this tty. 186796fd7ce5SGreg Kroah-Hartman * - do_tty_hangup no longer sees this file descriptor as 186896fd7ce5SGreg Kroah-Hartman * something that needs to be handled for hangups. 186996fd7ce5SGreg Kroah-Hartman */ 187096fd7ce5SGreg Kroah-Hartman tty_del_file(filp); 187196fd7ce5SGreg Kroah-Hartman 187296fd7ce5SGreg Kroah-Hartman /* 187396fd7ce5SGreg Kroah-Hartman * Perform some housekeeping before deciding whether to return. 187496fd7ce5SGreg Kroah-Hartman * 187596fd7ce5SGreg Kroah-Hartman * If _either_ side is closing, make sure there aren't any 187696fd7ce5SGreg Kroah-Hartman * processes that still think tty or o_tty is their controlling 187796fd7ce5SGreg Kroah-Hartman * tty. 187896fd7ce5SGreg Kroah-Hartman */ 1879324c1650SPeter Hurley if (!tty->count) { 188096fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 188196fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 18827ffb6da9SPeter Hurley if (o_tty) 188396fd7ce5SGreg Kroah-Hartman session_clear_tty(o_tty->session); 188496fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 188596fd7ce5SGreg Kroah-Hartman } 188696fd7ce5SGreg Kroah-Hartman 1887324c1650SPeter Hurley /* check whether both sides are closing ... */ 18887ffb6da9SPeter Hurley final = !tty->count && !(o_tty && o_tty->count); 1889324c1650SPeter Hurley 18902aff5e2bSPeter Hurley tty_unlock_slave(o_tty); 18912aff5e2bSPeter Hurley tty_unlock(tty); 18922aff5e2bSPeter Hurley 189304980706SPeter Hurley /* At this point, the tty->count == 0 should ensure a dead tty 1894d155255aSAlan Cox cannot be re-opened by a racing opener */ 189596fd7ce5SGreg Kroah-Hartman 1896324c1650SPeter Hurley if (!final) 189796fd7ce5SGreg Kroah-Hartman return 0; 189896fd7ce5SGreg Kroah-Hartman 1899accff793SPeter Hurley tty_debug_hangup(tty, "final close\n"); 190096fd7ce5SGreg Kroah-Hartman /* 190196fd7ce5SGreg Kroah-Hartman * Ask the line discipline code to release its structures 190296fd7ce5SGreg Kroah-Hartman */ 190362462aefSPeter Hurley tty_ldisc_release(tty); 1904a2965b7bSPeter Hurley 1905a2965b7bSPeter Hurley /* Wait for pending work before tty destruction commmences */ 1906a2965b7bSPeter Hurley tty_flush_works(tty); 1907a2965b7bSPeter Hurley 1908accff793SPeter Hurley tty_debug_hangup(tty, "freeing structure...\n"); 190996fd7ce5SGreg Kroah-Hartman /* 191096fd7ce5SGreg Kroah-Hartman * The release_tty function takes care of the details of clearing 191189c8d91eSAlan Cox * the slots and preserving the termios structure. The tty_unlock_pair 191289c8d91eSAlan Cox * should be safe as we keep a kref while the tty is locked (so the 191389c8d91eSAlan Cox * unlock never unlocks a freed tty). 191496fd7ce5SGreg Kroah-Hartman */ 1915d155255aSAlan Cox mutex_lock(&tty_mutex); 191696fd7ce5SGreg Kroah-Hartman release_tty(tty, idx); 1917d155255aSAlan Cox mutex_unlock(&tty_mutex); 191896fd7ce5SGreg Kroah-Hartman 191996fd7ce5SGreg Kroah-Hartman return 0; 192096fd7ce5SGreg Kroah-Hartman } 192196fd7ce5SGreg Kroah-Hartman 192296fd7ce5SGreg Kroah-Hartman /** 192352494eebSPeter Hurley * tty_open_current_tty - get locked tty of current task 1924b82154acSJiri Slaby * @device: device number 1925b82154acSJiri Slaby * @filp: file pointer to tty 192652494eebSPeter Hurley * @return: locked tty of the current task iff @device is /dev/tty 192752494eebSPeter Hurley * 192852494eebSPeter Hurley * Performs a re-open of the current task's controlling tty. 1929b82154acSJiri Slaby * 1930b82154acSJiri Slaby * We cannot return driver and index like for the other nodes because 1931b82154acSJiri Slaby * devpts will not work then. It expects inodes to be from devpts FS. 1932b82154acSJiri Slaby */ 1933b82154acSJiri Slaby static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) 1934b82154acSJiri Slaby { 1935b82154acSJiri Slaby struct tty_struct *tty; 193652494eebSPeter Hurley int retval; 1937b82154acSJiri Slaby 1938b82154acSJiri Slaby if (device != MKDEV(TTYAUX_MAJOR, 0)) 1939b82154acSJiri Slaby return NULL; 1940b82154acSJiri Slaby 1941b82154acSJiri Slaby tty = get_current_tty(); 1942b82154acSJiri Slaby if (!tty) 1943b82154acSJiri Slaby return ERR_PTR(-ENXIO); 1944b82154acSJiri Slaby 1945b82154acSJiri Slaby filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ 1946b82154acSJiri Slaby /* noctty = 1; */ 194752494eebSPeter Hurley tty_lock(tty); 194852494eebSPeter Hurley tty_kref_put(tty); /* safe to drop the kref now */ 194952494eebSPeter Hurley 195052494eebSPeter Hurley retval = tty_reopen(tty); 195152494eebSPeter Hurley if (retval < 0) { 195252494eebSPeter Hurley tty_unlock(tty); 195352494eebSPeter Hurley tty = ERR_PTR(retval); 195452494eebSPeter Hurley } 1955b82154acSJiri Slaby return tty; 1956b82154acSJiri Slaby } 1957b82154acSJiri Slaby 1958b82154acSJiri Slaby /** 19595b5e7040SJiri Slaby * tty_lookup_driver - lookup a tty driver for a given device file 19605b5e7040SJiri Slaby * @device: device number 19615b5e7040SJiri Slaby * @filp: file pointer to tty 19625b5e7040SJiri Slaby * @noctty: set if the device should not become a controlling tty 19635b5e7040SJiri Slaby * @index: index for the device in the @return driver 19645b5e7040SJiri Slaby * @return: driver for this inode (with increased refcount) 19655b5e7040SJiri Slaby * 19665b5e7040SJiri Slaby * If @return is not erroneous, the caller is responsible to decrement the 19675b5e7040SJiri Slaby * refcount by tty_driver_kref_put. 19685b5e7040SJiri Slaby * 19695b5e7040SJiri Slaby * Locking: tty_mutex protects get_tty_driver 19705b5e7040SJiri Slaby */ 19715b5e7040SJiri Slaby static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp, 19725b5e7040SJiri Slaby int *noctty, int *index) 19735b5e7040SJiri Slaby { 19745b5e7040SJiri Slaby struct tty_driver *driver; 19755b5e7040SJiri Slaby 19762cd0050cSJiri Slaby switch (device) { 19775b5e7040SJiri Slaby #ifdef CONFIG_VT 19782cd0050cSJiri Slaby case MKDEV(TTY_MAJOR, 0): { 19795b5e7040SJiri Slaby extern struct tty_driver *console_driver; 19805b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 19815b5e7040SJiri Slaby *index = fg_console; 19825b5e7040SJiri Slaby *noctty = 1; 19832cd0050cSJiri Slaby break; 19845b5e7040SJiri Slaby } 19855b5e7040SJiri Slaby #endif 19862cd0050cSJiri Slaby case MKDEV(TTYAUX_MAJOR, 1): { 19875b5e7040SJiri Slaby struct tty_driver *console_driver = console_device(index); 19885b5e7040SJiri Slaby if (console_driver) { 19895b5e7040SJiri Slaby driver = tty_driver_kref_get(console_driver); 19905b5e7040SJiri Slaby if (driver) { 19915b5e7040SJiri Slaby /* Don't let /dev/console block */ 19925b5e7040SJiri Slaby filp->f_flags |= O_NONBLOCK; 19935b5e7040SJiri Slaby *noctty = 1; 19942cd0050cSJiri Slaby break; 19955b5e7040SJiri Slaby } 19965b5e7040SJiri Slaby } 19975b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 19985b5e7040SJiri Slaby } 19992cd0050cSJiri Slaby default: 20005b5e7040SJiri Slaby driver = get_tty_driver(device, index); 20015b5e7040SJiri Slaby if (!driver) 20025b5e7040SJiri Slaby return ERR_PTR(-ENODEV); 20032cd0050cSJiri Slaby break; 20042cd0050cSJiri Slaby } 20055b5e7040SJiri Slaby return driver; 20065b5e7040SJiri Slaby } 20075b5e7040SJiri Slaby 20085b5e7040SJiri Slaby /** 200996fd7ce5SGreg Kroah-Hartman * tty_open - open a tty device 201096fd7ce5SGreg Kroah-Hartman * @inode: inode of device file 201196fd7ce5SGreg Kroah-Hartman * @filp: file pointer to tty 201296fd7ce5SGreg Kroah-Hartman * 201396fd7ce5SGreg Kroah-Hartman * tty_open and tty_release keep up the tty count that contains the 201496fd7ce5SGreg Kroah-Hartman * number of opens done on a tty. We cannot use the inode-count, as 201596fd7ce5SGreg Kroah-Hartman * different inodes might point to the same tty. 201696fd7ce5SGreg Kroah-Hartman * 201796fd7ce5SGreg Kroah-Hartman * Open-counting is needed for pty masters, as well as for keeping 201896fd7ce5SGreg Kroah-Hartman * track of serial lines: DTR is dropped when the last close happens. 201996fd7ce5SGreg Kroah-Hartman * (This is not done solely through tty->count, now. - Ted 1/27/92) 202096fd7ce5SGreg Kroah-Hartman * 202196fd7ce5SGreg Kroah-Hartman * The termios state of a pty is reset on first open so that 202296fd7ce5SGreg Kroah-Hartman * settings don't persist across reuse. 202396fd7ce5SGreg Kroah-Hartman * 20245b5e7040SJiri Slaby * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev. 202596fd7ce5SGreg Kroah-Hartman * tty->count should protect the rest. 202696fd7ce5SGreg Kroah-Hartman * ->siglock protects ->signal/->sighand 202789c8d91eSAlan Cox * 202889c8d91eSAlan Cox * Note: the tty_unlock/lock cases without a ref are only safe due to 202989c8d91eSAlan Cox * tty_mutex 203096fd7ce5SGreg Kroah-Hartman */ 203196fd7ce5SGreg Kroah-Hartman 203296fd7ce5SGreg Kroah-Hartman static int tty_open(struct inode *inode, struct file *filp) 203396fd7ce5SGreg Kroah-Hartman { 2034b82154acSJiri Slaby struct tty_struct *tty; 203596fd7ce5SGreg Kroah-Hartman int noctty, retval; 2036b82154acSJiri Slaby struct tty_driver *driver = NULL; 203796fd7ce5SGreg Kroah-Hartman int index; 203896fd7ce5SGreg Kroah-Hartman dev_t device = inode->i_rdev; 203996fd7ce5SGreg Kroah-Hartman unsigned saved_flags = filp->f_flags; 204096fd7ce5SGreg Kroah-Hartman 204196fd7ce5SGreg Kroah-Hartman nonseekable_open(inode, filp); 204296fd7ce5SGreg Kroah-Hartman 204396fd7ce5SGreg Kroah-Hartman retry_open: 2044fa90e1c9SJiri Slaby retval = tty_alloc_file(filp); 2045fa90e1c9SJiri Slaby if (retval) 2046fa90e1c9SJiri Slaby return -ENOMEM; 2047fa90e1c9SJiri Slaby 204896fd7ce5SGreg Kroah-Hartman noctty = filp->f_flags & O_NOCTTY; 204996fd7ce5SGreg Kroah-Hartman index = -1; 205096fd7ce5SGreg Kroah-Hartman retval = 0; 205196fd7ce5SGreg Kroah-Hartman 2052b82154acSJiri Slaby tty = tty_open_current_tty(device, filp); 205352494eebSPeter Hurley if (!tty) { 205452494eebSPeter Hurley mutex_lock(&tty_mutex); 20555b5e7040SJiri Slaby driver = tty_lookup_driver(device, filp, &noctty, &index); 20565b5e7040SJiri Slaby if (IS_ERR(driver)) { 2057ba5db448SJiri Slaby retval = PTR_ERR(driver); 2058ba5db448SJiri Slaby goto err_unlock; 205996fd7ce5SGreg Kroah-Hartman } 206096fd7ce5SGreg Kroah-Hartman 206196fd7ce5SGreg Kroah-Hartman /* check whether we're reopening an existing tty */ 206296fd7ce5SGreg Kroah-Hartman tty = tty_driver_lookup_tty(driver, inode, index); 206396fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty)) { 2064ba5db448SJiri Slaby retval = PTR_ERR(tty); 2065ba5db448SJiri Slaby goto err_unlock; 206696fd7ce5SGreg Kroah-Hartman } 206796fd7ce5SGreg Kroah-Hartman 206896fd7ce5SGreg Kroah-Hartman if (tty) { 2069aa3cb814SPeter Hurley mutex_unlock(&tty_mutex); 207089c8d91eSAlan Cox tty_lock(tty); 2071aa3cb814SPeter Hurley /* safe to drop the kref from tty_driver_lookup_tty() */ 2072aa3cb814SPeter Hurley tty_kref_put(tty); 207396fd7ce5SGreg Kroah-Hartman retval = tty_reopen(tty); 207489c8d91eSAlan Cox if (retval < 0) { 207589c8d91eSAlan Cox tty_unlock(tty); 207696fd7ce5SGreg Kroah-Hartman tty = ERR_PTR(retval); 207789c8d91eSAlan Cox } 2078aa3cb814SPeter Hurley } else { /* Returns with the tty_lock held for now */ 2079593a27c4SKonstantin Khlebnikov tty = tty_init_dev(driver, index); 208096fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 2081aa3cb814SPeter Hurley } 2082aa3cb814SPeter Hurley 208396fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(driver); 208452494eebSPeter Hurley } 208552494eebSPeter Hurley 208696fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty)) { 2087ba5db448SJiri Slaby retval = PTR_ERR(tty); 2088ba5db448SJiri Slaby goto err_file; 208996fd7ce5SGreg Kroah-Hartman } 209096fd7ce5SGreg Kroah-Hartman 2091fa90e1c9SJiri Slaby tty_add_file(tty, filp); 209296fd7ce5SGreg Kroah-Hartman 20939de44bd6SJiri Slaby check_tty_count(tty, __func__); 209496fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 209596fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_MASTER) 209696fd7ce5SGreg Kroah-Hartman noctty = 1; 2097accff793SPeter Hurley 2098accff793SPeter Hurley tty_debug_hangup(tty, "(tty count=%d)\n", tty->count); 2099accff793SPeter Hurley 210096fd7ce5SGreg Kroah-Hartman if (tty->ops->open) 210196fd7ce5SGreg Kroah-Hartman retval = tty->ops->open(tty, filp); 210296fd7ce5SGreg Kroah-Hartman else 210396fd7ce5SGreg Kroah-Hartman retval = -ENODEV; 210496fd7ce5SGreg Kroah-Hartman filp->f_flags = saved_flags; 210596fd7ce5SGreg Kroah-Hartman 210696fd7ce5SGreg Kroah-Hartman if (retval) { 2107accff793SPeter Hurley tty_debug_hangup(tty, "error %d, releasing...\n", retval); 2108accff793SPeter Hurley 210989c8d91eSAlan Cox tty_unlock(tty); /* need to call tty_release without BTM */ 211096fd7ce5SGreg Kroah-Hartman tty_release(inode, filp); 211196fd7ce5SGreg Kroah-Hartman if (retval != -ERESTARTSYS) 211296fd7ce5SGreg Kroah-Hartman return retval; 211396fd7ce5SGreg Kroah-Hartman 211496fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 211596fd7ce5SGreg Kroah-Hartman return retval; 211696fd7ce5SGreg Kroah-Hartman 211796fd7ce5SGreg Kroah-Hartman schedule(); 211896fd7ce5SGreg Kroah-Hartman /* 211996fd7ce5SGreg Kroah-Hartman * Need to reset f_op in case a hangup happened. 212096fd7ce5SGreg Kroah-Hartman */ 21211256937fSPeter Hurley if (tty_hung_up_p(filp)) 212296fd7ce5SGreg Kroah-Hartman filp->f_op = &tty_fops; 212396fd7ce5SGreg Kroah-Hartman goto retry_open; 212496fd7ce5SGreg Kroah-Hartman } 2125d4855e1fSPeter Hurley clear_bit(TTY_HUPPED, &tty->flags); 212696fd7ce5SGreg Kroah-Hartman 212796fd7ce5SGreg Kroah-Hartman 21282c411c11SPeter Hurley read_lock(&tasklist_lock); 212996fd7ce5SGreg Kroah-Hartman spin_lock_irq(¤t->sighand->siglock); 213096fd7ce5SGreg Kroah-Hartman if (!noctty && 213196fd7ce5SGreg Kroah-Hartman current->signal->leader && 213296fd7ce5SGreg Kroah-Hartman !current->signal->tty && 21330c556271SJann Horn tty->session == NULL) { 21340c556271SJann Horn /* 21350c556271SJann Horn * Don't let a process that only has write access to the tty 21360c556271SJann Horn * obtain the privileges associated with having a tty as 21370c556271SJann Horn * controlling terminal (being able to reopen it with full 21380c556271SJann Horn * access through /dev/tty, being able to perform pushback). 21390c556271SJann Horn * Many distributions set the group of all ttys to "tty" and 21400c556271SJann Horn * grant write-only access to all terminals for setgid tty 21410c556271SJann Horn * binaries, which should not imply full privileges on all ttys. 21420c556271SJann Horn * 21430c556271SJann Horn * This could theoretically break old code that performs open() 21440c556271SJann Horn * on a write-only file descriptor. In that case, it might be 21450c556271SJann Horn * necessary to also permit this if 21460c556271SJann Horn * inode_permission(inode, MAY_READ) == 0. 21470c556271SJann Horn */ 21480c556271SJann Horn if (filp->f_mode & FMODE_READ) 2149bce65f18SPeter Hurley __proc_set_tty(tty); 21500c556271SJann Horn } 215196fd7ce5SGreg Kroah-Hartman spin_unlock_irq(¤t->sighand->siglock); 21522c411c11SPeter Hurley read_unlock(&tasklist_lock); 215389c8d91eSAlan Cox tty_unlock(tty); 215496fd7ce5SGreg Kroah-Hartman return 0; 2155ba5db448SJiri Slaby err_unlock: 2156ba5db448SJiri Slaby mutex_unlock(&tty_mutex); 2157ba5db448SJiri Slaby /* after locks to avoid deadlock */ 2158ba5db448SJiri Slaby if (!IS_ERR_OR_NULL(driver)) 2159ba5db448SJiri Slaby tty_driver_kref_put(driver); 2160ba5db448SJiri Slaby err_file: 2161ba5db448SJiri Slaby tty_free_file(filp); 2162ba5db448SJiri Slaby return retval; 216396fd7ce5SGreg Kroah-Hartman } 216496fd7ce5SGreg Kroah-Hartman 216596fd7ce5SGreg Kroah-Hartman 216696fd7ce5SGreg Kroah-Hartman 216796fd7ce5SGreg Kroah-Hartman /** 216896fd7ce5SGreg Kroah-Hartman * tty_poll - check tty status 216996fd7ce5SGreg Kroah-Hartman * @filp: file being polled 217096fd7ce5SGreg Kroah-Hartman * @wait: poll wait structures to update 217196fd7ce5SGreg Kroah-Hartman * 217296fd7ce5SGreg Kroah-Hartman * Call the line discipline polling method to obtain the poll 217396fd7ce5SGreg Kroah-Hartman * status of the device. 217496fd7ce5SGreg Kroah-Hartman * 217596fd7ce5SGreg Kroah-Hartman * Locking: locks called line discipline but ldisc poll method 217696fd7ce5SGreg Kroah-Hartman * may be re-entered freely by other callers. 217796fd7ce5SGreg Kroah-Hartman */ 217896fd7ce5SGreg Kroah-Hartman 217996fd7ce5SGreg Kroah-Hartman static unsigned int tty_poll(struct file *filp, poll_table *wait) 218096fd7ce5SGreg Kroah-Hartman { 218196fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 218296fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 218396fd7ce5SGreg Kroah-Hartman int ret = 0; 218496fd7ce5SGreg Kroah-Hartman 21856131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_poll")) 218696fd7ce5SGreg Kroah-Hartman return 0; 218796fd7ce5SGreg Kroah-Hartman 218896fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 218996fd7ce5SGreg Kroah-Hartman if (ld->ops->poll) 2190c961bfb1SPeter Hurley ret = ld->ops->poll(tty, filp, wait); 219196fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 219296fd7ce5SGreg Kroah-Hartman return ret; 219396fd7ce5SGreg Kroah-Hartman } 219496fd7ce5SGreg Kroah-Hartman 219596fd7ce5SGreg Kroah-Hartman static int __tty_fasync(int fd, struct file *filp, int on) 219696fd7ce5SGreg Kroah-Hartman { 219796fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(filp); 2198f6c8dbe6SPeter Hurley struct tty_ldisc *ldisc; 219996fd7ce5SGreg Kroah-Hartman unsigned long flags; 220096fd7ce5SGreg Kroah-Hartman int retval = 0; 220196fd7ce5SGreg Kroah-Hartman 22026131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(filp), "tty_fasync")) 220396fd7ce5SGreg Kroah-Hartman goto out; 220496fd7ce5SGreg Kroah-Hartman 220596fd7ce5SGreg Kroah-Hartman retval = fasync_helper(fd, filp, on, &tty->fasync); 220696fd7ce5SGreg Kroah-Hartman if (retval <= 0) 220796fd7ce5SGreg Kroah-Hartman goto out; 220896fd7ce5SGreg Kroah-Hartman 2209f6c8dbe6SPeter Hurley ldisc = tty_ldisc_ref(tty); 2210f6c8dbe6SPeter Hurley if (ldisc) { 2211f6c8dbe6SPeter Hurley if (ldisc->ops->fasync) 2212f6c8dbe6SPeter Hurley ldisc->ops->fasync(tty, on); 2213f6c8dbe6SPeter Hurley tty_ldisc_deref(ldisc); 2214f6c8dbe6SPeter Hurley } 2215f6c8dbe6SPeter Hurley 221696fd7ce5SGreg Kroah-Hartman if (on) { 221796fd7ce5SGreg Kroah-Hartman enum pid_type type; 221896fd7ce5SGreg Kroah-Hartman struct pid *pid; 2219f6c8dbe6SPeter Hurley 222096fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 222196fd7ce5SGreg Kroah-Hartman if (tty->pgrp) { 222296fd7ce5SGreg Kroah-Hartman pid = tty->pgrp; 222396fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PGID; 222496fd7ce5SGreg Kroah-Hartman } else { 222596fd7ce5SGreg Kroah-Hartman pid = task_pid(current); 222696fd7ce5SGreg Kroah-Hartman type = PIDTYPE_PID; 222796fd7ce5SGreg Kroah-Hartman } 222896fd7ce5SGreg Kroah-Hartman get_pid(pid); 222996fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 2230e0b93eddSJeff Layton __f_setown(filp, pid, type, 0); 223196fd7ce5SGreg Kroah-Hartman put_pid(pid); 2232e0b93eddSJeff Layton retval = 0; 223396fd7ce5SGreg Kroah-Hartman } 223496fd7ce5SGreg Kroah-Hartman out: 223596fd7ce5SGreg Kroah-Hartman return retval; 223696fd7ce5SGreg Kroah-Hartman } 223796fd7ce5SGreg Kroah-Hartman 223896fd7ce5SGreg Kroah-Hartman static int tty_fasync(int fd, struct file *filp, int on) 223996fd7ce5SGreg Kroah-Hartman { 224089c8d91eSAlan Cox struct tty_struct *tty = file_tty(filp); 224196fd7ce5SGreg Kroah-Hartman int retval; 224289c8d91eSAlan Cox 224389c8d91eSAlan Cox tty_lock(tty); 224496fd7ce5SGreg Kroah-Hartman retval = __tty_fasync(fd, filp, on); 224589c8d91eSAlan Cox tty_unlock(tty); 224689c8d91eSAlan Cox 224796fd7ce5SGreg Kroah-Hartman return retval; 224896fd7ce5SGreg Kroah-Hartman } 224996fd7ce5SGreg Kroah-Hartman 225096fd7ce5SGreg Kroah-Hartman /** 225196fd7ce5SGreg Kroah-Hartman * tiocsti - fake input character 225296fd7ce5SGreg Kroah-Hartman * @tty: tty to fake input into 225396fd7ce5SGreg Kroah-Hartman * @p: pointer to character 225496fd7ce5SGreg Kroah-Hartman * 225596fd7ce5SGreg Kroah-Hartman * Fake input to a tty device. Does the necessary locking and 225696fd7ce5SGreg Kroah-Hartman * input management. 225796fd7ce5SGreg Kroah-Hartman * 225896fd7ce5SGreg Kroah-Hartman * FIXME: does not honour flow control ?? 225996fd7ce5SGreg Kroah-Hartman * 226096fd7ce5SGreg Kroah-Hartman * Locking: 2261137084bbSPeter Hurley * Called functions take tty_ldiscs_lock 226296fd7ce5SGreg Kroah-Hartman * current->signal->tty check is safe without locks 226396fd7ce5SGreg Kroah-Hartman * 226496fd7ce5SGreg Kroah-Hartman * FIXME: may race normal receive processing 226596fd7ce5SGreg Kroah-Hartman */ 226696fd7ce5SGreg Kroah-Hartman 226796fd7ce5SGreg Kroah-Hartman static int tiocsti(struct tty_struct *tty, char __user *p) 226896fd7ce5SGreg Kroah-Hartman { 226996fd7ce5SGreg Kroah-Hartman char ch, mbz = 0; 227096fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 227196fd7ce5SGreg Kroah-Hartman 227296fd7ce5SGreg Kroah-Hartman if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) 227396fd7ce5SGreg Kroah-Hartman return -EPERM; 227496fd7ce5SGreg Kroah-Hartman if (get_user(ch, p)) 227596fd7ce5SGreg Kroah-Hartman return -EFAULT; 227696fd7ce5SGreg Kroah-Hartman tty_audit_tiocsti(tty, ch); 227796fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 227896fd7ce5SGreg Kroah-Hartman ld->ops->receive_buf(tty, &ch, &mbz, 1); 227996fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 228096fd7ce5SGreg Kroah-Hartman return 0; 228196fd7ce5SGreg Kroah-Hartman } 228296fd7ce5SGreg Kroah-Hartman 228396fd7ce5SGreg Kroah-Hartman /** 228496fd7ce5SGreg Kroah-Hartman * tiocgwinsz - implement window query ioctl 228596fd7ce5SGreg Kroah-Hartman * @tty; tty 228696fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 228796fd7ce5SGreg Kroah-Hartman * 228896fd7ce5SGreg Kroah-Hartman * Copies the kernel idea of the window size into the user buffer. 228996fd7ce5SGreg Kroah-Hartman * 2290dee4a0beSPeter Hurley * Locking: tty->winsize_mutex is taken to ensure the winsize data 229196fd7ce5SGreg Kroah-Hartman * is consistent. 229296fd7ce5SGreg Kroah-Hartman */ 229396fd7ce5SGreg Kroah-Hartman 229496fd7ce5SGreg Kroah-Hartman static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) 229596fd7ce5SGreg Kroah-Hartman { 229696fd7ce5SGreg Kroah-Hartman int err; 229796fd7ce5SGreg Kroah-Hartman 2298dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 229996fd7ce5SGreg Kroah-Hartman err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); 2300dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 230196fd7ce5SGreg Kroah-Hartman 230296fd7ce5SGreg Kroah-Hartman return err ? -EFAULT: 0; 230396fd7ce5SGreg Kroah-Hartman } 230496fd7ce5SGreg Kroah-Hartman 230596fd7ce5SGreg Kroah-Hartman /** 230696fd7ce5SGreg Kroah-Hartman * tty_do_resize - resize event 230796fd7ce5SGreg Kroah-Hartman * @tty: tty being resized 230896fd7ce5SGreg Kroah-Hartman * @rows: rows (character) 230996fd7ce5SGreg Kroah-Hartman * @cols: cols (character) 231096fd7ce5SGreg Kroah-Hartman * 231196fd7ce5SGreg Kroah-Hartman * Update the termios variables and send the necessary signals to 231296fd7ce5SGreg Kroah-Hartman * peform a terminal resize correctly 231396fd7ce5SGreg Kroah-Hartman */ 231496fd7ce5SGreg Kroah-Hartman 231596fd7ce5SGreg Kroah-Hartman int tty_do_resize(struct tty_struct *tty, struct winsize *ws) 231696fd7ce5SGreg Kroah-Hartman { 231796fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 231896fd7ce5SGreg Kroah-Hartman 231996fd7ce5SGreg Kroah-Hartman /* Lock the tty */ 2320dee4a0beSPeter Hurley mutex_lock(&tty->winsize_mutex); 232196fd7ce5SGreg Kroah-Hartman if (!memcmp(ws, &tty->winsize, sizeof(*ws))) 232296fd7ce5SGreg Kroah-Hartman goto done; 232396fd7ce5SGreg Kroah-Hartman 23245b239542SPeter Hurley /* Signal the foreground process group */ 23255b239542SPeter Hurley pgrp = tty_get_pgrp(tty); 232696fd7ce5SGreg Kroah-Hartman if (pgrp) 232796fd7ce5SGreg Kroah-Hartman kill_pgrp(pgrp, SIGWINCH, 1); 232896fd7ce5SGreg Kroah-Hartman put_pid(pgrp); 232996fd7ce5SGreg Kroah-Hartman 233096fd7ce5SGreg Kroah-Hartman tty->winsize = *ws; 233196fd7ce5SGreg Kroah-Hartman done: 2332dee4a0beSPeter Hurley mutex_unlock(&tty->winsize_mutex); 233396fd7ce5SGreg Kroah-Hartman return 0; 233496fd7ce5SGreg Kroah-Hartman } 23354d334fd1SMartin Schwidefsky EXPORT_SYMBOL(tty_do_resize); 233696fd7ce5SGreg Kroah-Hartman 233796fd7ce5SGreg Kroah-Hartman /** 233896fd7ce5SGreg Kroah-Hartman * tiocswinsz - implement window size set ioctl 233996fd7ce5SGreg Kroah-Hartman * @tty; tty side of tty 234096fd7ce5SGreg Kroah-Hartman * @arg: user buffer for result 234196fd7ce5SGreg Kroah-Hartman * 234296fd7ce5SGreg Kroah-Hartman * Copies the user idea of the window size to the kernel. Traditionally 234396fd7ce5SGreg Kroah-Hartman * this is just advisory information but for the Linux console it 234496fd7ce5SGreg Kroah-Hartman * actually has driver level meaning and triggers a VC resize. 234596fd7ce5SGreg Kroah-Hartman * 234696fd7ce5SGreg Kroah-Hartman * Locking: 234725985edcSLucas De Marchi * Driver dependent. The default do_resize method takes the 234896fd7ce5SGreg Kroah-Hartman * tty termios mutex and ctrl_lock. The console takes its own lock 234996fd7ce5SGreg Kroah-Hartman * then calls into the default method. 235096fd7ce5SGreg Kroah-Hartman */ 235196fd7ce5SGreg Kroah-Hartman 235296fd7ce5SGreg Kroah-Hartman static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) 235396fd7ce5SGreg Kroah-Hartman { 235496fd7ce5SGreg Kroah-Hartman struct winsize tmp_ws; 235596fd7ce5SGreg Kroah-Hartman if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) 235696fd7ce5SGreg Kroah-Hartman return -EFAULT; 235796fd7ce5SGreg Kroah-Hartman 235896fd7ce5SGreg Kroah-Hartman if (tty->ops->resize) 235996fd7ce5SGreg Kroah-Hartman return tty->ops->resize(tty, &tmp_ws); 236096fd7ce5SGreg Kroah-Hartman else 236196fd7ce5SGreg Kroah-Hartman return tty_do_resize(tty, &tmp_ws); 236296fd7ce5SGreg Kroah-Hartman } 236396fd7ce5SGreg Kroah-Hartman 236496fd7ce5SGreg Kroah-Hartman /** 236596fd7ce5SGreg Kroah-Hartman * tioccons - allow admin to move logical console 236696fd7ce5SGreg Kroah-Hartman * @file: the file to become console 236796fd7ce5SGreg Kroah-Hartman * 236825985edcSLucas De Marchi * Allow the administrator to move the redirected console device 236996fd7ce5SGreg Kroah-Hartman * 237096fd7ce5SGreg Kroah-Hartman * Locking: uses redirect_lock to guard the redirect information 237196fd7ce5SGreg Kroah-Hartman */ 237296fd7ce5SGreg Kroah-Hartman 237396fd7ce5SGreg Kroah-Hartman static int tioccons(struct file *file) 237496fd7ce5SGreg Kroah-Hartman { 237596fd7ce5SGreg Kroah-Hartman if (!capable(CAP_SYS_ADMIN)) 237696fd7ce5SGreg Kroah-Hartman return -EPERM; 237796fd7ce5SGreg Kroah-Hartman if (file->f_op->write == redirected_tty_write) { 237896fd7ce5SGreg Kroah-Hartman struct file *f; 237996fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 238096fd7ce5SGreg Kroah-Hartman f = redirect; 238196fd7ce5SGreg Kroah-Hartman redirect = NULL; 238296fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 238396fd7ce5SGreg Kroah-Hartman if (f) 238496fd7ce5SGreg Kroah-Hartman fput(f); 238596fd7ce5SGreg Kroah-Hartman return 0; 238696fd7ce5SGreg Kroah-Hartman } 238796fd7ce5SGreg Kroah-Hartman spin_lock(&redirect_lock); 238896fd7ce5SGreg Kroah-Hartman if (redirect) { 238996fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 239096fd7ce5SGreg Kroah-Hartman return -EBUSY; 239196fd7ce5SGreg Kroah-Hartman } 2392cb0942b8SAl Viro redirect = get_file(file); 239396fd7ce5SGreg Kroah-Hartman spin_unlock(&redirect_lock); 239496fd7ce5SGreg Kroah-Hartman return 0; 239596fd7ce5SGreg Kroah-Hartman } 239696fd7ce5SGreg Kroah-Hartman 239796fd7ce5SGreg Kroah-Hartman /** 239896fd7ce5SGreg Kroah-Hartman * fionbio - non blocking ioctl 239996fd7ce5SGreg Kroah-Hartman * @file: file to set blocking value 240096fd7ce5SGreg Kroah-Hartman * @p: user parameter 240196fd7ce5SGreg Kroah-Hartman * 240296fd7ce5SGreg Kroah-Hartman * Historical tty interfaces had a blocking control ioctl before 240396fd7ce5SGreg Kroah-Hartman * the generic functionality existed. This piece of history is preserved 240496fd7ce5SGreg Kroah-Hartman * in the expected tty API of posix OS's. 240596fd7ce5SGreg Kroah-Hartman * 240696fd7ce5SGreg Kroah-Hartman * Locking: none, the open file handle ensures it won't go away. 240796fd7ce5SGreg Kroah-Hartman */ 240896fd7ce5SGreg Kroah-Hartman 240996fd7ce5SGreg Kroah-Hartman static int fionbio(struct file *file, int __user *p) 241096fd7ce5SGreg Kroah-Hartman { 241196fd7ce5SGreg Kroah-Hartman int nonblock; 241296fd7ce5SGreg Kroah-Hartman 241396fd7ce5SGreg Kroah-Hartman if (get_user(nonblock, p)) 241496fd7ce5SGreg Kroah-Hartman return -EFAULT; 241596fd7ce5SGreg Kroah-Hartman 241696fd7ce5SGreg Kroah-Hartman spin_lock(&file->f_lock); 241796fd7ce5SGreg Kroah-Hartman if (nonblock) 241896fd7ce5SGreg Kroah-Hartman file->f_flags |= O_NONBLOCK; 241996fd7ce5SGreg Kroah-Hartman else 242096fd7ce5SGreg Kroah-Hartman file->f_flags &= ~O_NONBLOCK; 242196fd7ce5SGreg Kroah-Hartman spin_unlock(&file->f_lock); 242296fd7ce5SGreg Kroah-Hartman return 0; 242396fd7ce5SGreg Kroah-Hartman } 242496fd7ce5SGreg Kroah-Hartman 242596fd7ce5SGreg Kroah-Hartman /** 242696fd7ce5SGreg Kroah-Hartman * tiocsctty - set controlling tty 242796fd7ce5SGreg Kroah-Hartman * @tty: tty structure 242896fd7ce5SGreg Kroah-Hartman * @arg: user argument 242996fd7ce5SGreg Kroah-Hartman * 243096fd7ce5SGreg Kroah-Hartman * This ioctl is used to manage job control. It permits a session 243196fd7ce5SGreg Kroah-Hartman * leader to set this tty as the controlling tty for the session. 243296fd7ce5SGreg Kroah-Hartman * 243396fd7ce5SGreg Kroah-Hartman * Locking: 2434e218eb32SPeter Hurley * Takes tty_lock() to serialize proc_set_tty() for this tty 243596fd7ce5SGreg Kroah-Hartman * Takes tasklist_lock internally to walk sessions 243696fd7ce5SGreg Kroah-Hartman * Takes ->siglock() when updating signal->tty 243796fd7ce5SGreg Kroah-Hartman */ 243896fd7ce5SGreg Kroah-Hartman 24390c556271SJann Horn static int tiocsctty(struct tty_struct *tty, struct file *file, int arg) 244096fd7ce5SGreg Kroah-Hartman { 244196fd7ce5SGreg Kroah-Hartman int ret = 0; 244296fd7ce5SGreg Kroah-Hartman 2443e218eb32SPeter Hurley tty_lock(tty); 24442c411c11SPeter Hurley read_lock(&tasklist_lock); 24452c411c11SPeter Hurley 24462c411c11SPeter Hurley if (current->signal->leader && (task_session(current) == tty->session)) 24472c411c11SPeter Hurley goto unlock; 24482c411c11SPeter Hurley 244996fd7ce5SGreg Kroah-Hartman /* 245096fd7ce5SGreg Kroah-Hartman * The process must be a session leader and 245196fd7ce5SGreg Kroah-Hartman * not have a controlling tty already. 245296fd7ce5SGreg Kroah-Hartman */ 245396fd7ce5SGreg Kroah-Hartman if (!current->signal->leader || current->signal->tty) { 245496fd7ce5SGreg Kroah-Hartman ret = -EPERM; 245596fd7ce5SGreg Kroah-Hartman goto unlock; 245696fd7ce5SGreg Kroah-Hartman } 245796fd7ce5SGreg Kroah-Hartman 245896fd7ce5SGreg Kroah-Hartman if (tty->session) { 245996fd7ce5SGreg Kroah-Hartman /* 246096fd7ce5SGreg Kroah-Hartman * This tty is already the controlling 246196fd7ce5SGreg Kroah-Hartman * tty for another session group! 246296fd7ce5SGreg Kroah-Hartman */ 246396fd7ce5SGreg Kroah-Hartman if (arg == 1 && capable(CAP_SYS_ADMIN)) { 246496fd7ce5SGreg Kroah-Hartman /* 246596fd7ce5SGreg Kroah-Hartman * Steal it away 246696fd7ce5SGreg Kroah-Hartman */ 246796fd7ce5SGreg Kroah-Hartman session_clear_tty(tty->session); 246896fd7ce5SGreg Kroah-Hartman } else { 246996fd7ce5SGreg Kroah-Hartman ret = -EPERM; 247096fd7ce5SGreg Kroah-Hartman goto unlock; 247196fd7ce5SGreg Kroah-Hartman } 247296fd7ce5SGreg Kroah-Hartman } 24730c556271SJann Horn 24740c556271SJann Horn /* See the comment in tty_open(). */ 24750c556271SJann Horn if ((file->f_mode & FMODE_READ) == 0 && !capable(CAP_SYS_ADMIN)) { 24760c556271SJann Horn ret = -EPERM; 24770c556271SJann Horn goto unlock; 24780c556271SJann Horn } 24790c556271SJann Horn 2480bce65f18SPeter Hurley proc_set_tty(tty); 248196fd7ce5SGreg Kroah-Hartman unlock: 24822c411c11SPeter Hurley read_unlock(&tasklist_lock); 2483e218eb32SPeter Hurley tty_unlock(tty); 248496fd7ce5SGreg Kroah-Hartman return ret; 248596fd7ce5SGreg Kroah-Hartman } 248696fd7ce5SGreg Kroah-Hartman 248796fd7ce5SGreg Kroah-Hartman /** 248896fd7ce5SGreg Kroah-Hartman * tty_get_pgrp - return a ref counted pgrp pid 248996fd7ce5SGreg Kroah-Hartman * @tty: tty to read 249096fd7ce5SGreg Kroah-Hartman * 249196fd7ce5SGreg Kroah-Hartman * Returns a refcounted instance of the pid struct for the process 249296fd7ce5SGreg Kroah-Hartman * group controlling the tty. 249396fd7ce5SGreg Kroah-Hartman */ 249496fd7ce5SGreg Kroah-Hartman 249596fd7ce5SGreg Kroah-Hartman struct pid *tty_get_pgrp(struct tty_struct *tty) 249696fd7ce5SGreg Kroah-Hartman { 249796fd7ce5SGreg Kroah-Hartman unsigned long flags; 249896fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 249996fd7ce5SGreg Kroah-Hartman 250096fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 250196fd7ce5SGreg Kroah-Hartman pgrp = get_pid(tty->pgrp); 250296fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 250396fd7ce5SGreg Kroah-Hartman 250496fd7ce5SGreg Kroah-Hartman return pgrp; 250596fd7ce5SGreg Kroah-Hartman } 250696fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_get_pgrp); 250796fd7ce5SGreg Kroah-Hartman 2508e1c2296cSPeter Hurley /* 2509e1c2296cSPeter Hurley * This checks not only the pgrp, but falls back on the pid if no 2510e1c2296cSPeter Hurley * satisfactory pgrp is found. I dunno - gdb doesn't work correctly 2511e1c2296cSPeter Hurley * without this... 2512e1c2296cSPeter Hurley * 2513e1c2296cSPeter Hurley * The caller must hold rcu lock or the tasklist lock. 2514e1c2296cSPeter Hurley */ 2515e1c2296cSPeter Hurley static struct pid *session_of_pgrp(struct pid *pgrp) 2516e1c2296cSPeter Hurley { 2517e1c2296cSPeter Hurley struct task_struct *p; 2518e1c2296cSPeter Hurley struct pid *sid = NULL; 2519e1c2296cSPeter Hurley 2520e1c2296cSPeter Hurley p = pid_task(pgrp, PIDTYPE_PGID); 2521e1c2296cSPeter Hurley if (p == NULL) 2522e1c2296cSPeter Hurley p = pid_task(pgrp, PIDTYPE_PID); 2523e1c2296cSPeter Hurley if (p != NULL) 2524e1c2296cSPeter Hurley sid = task_session(p); 2525e1c2296cSPeter Hurley 2526e1c2296cSPeter Hurley return sid; 2527e1c2296cSPeter Hurley } 2528e1c2296cSPeter Hurley 252996fd7ce5SGreg Kroah-Hartman /** 253096fd7ce5SGreg Kroah-Hartman * tiocgpgrp - get process group 253196fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 253225985edcSLucas De Marchi * @real_tty: tty side of the tty passed by the user if a pty else the tty 253396fd7ce5SGreg Kroah-Hartman * @p: returned pid 253496fd7ce5SGreg Kroah-Hartman * 253596fd7ce5SGreg Kroah-Hartman * Obtain the process group of the tty. If there is no process group 253696fd7ce5SGreg Kroah-Hartman * return an error. 253796fd7ce5SGreg Kroah-Hartman * 253896fd7ce5SGreg Kroah-Hartman * Locking: none. Reference to current->signal->tty is safe. 253996fd7ce5SGreg Kroah-Hartman */ 254096fd7ce5SGreg Kroah-Hartman 254196fd7ce5SGreg Kroah-Hartman static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 254296fd7ce5SGreg Kroah-Hartman { 254396fd7ce5SGreg Kroah-Hartman struct pid *pid; 254496fd7ce5SGreg Kroah-Hartman int ret; 254596fd7ce5SGreg Kroah-Hartman /* 254696fd7ce5SGreg Kroah-Hartman * (tty == real_tty) is a cheap way of 254796fd7ce5SGreg Kroah-Hartman * testing if the tty is NOT a master pty. 254896fd7ce5SGreg Kroah-Hartman */ 254996fd7ce5SGreg Kroah-Hartman if (tty == real_tty && current->signal->tty != real_tty) 255096fd7ce5SGreg Kroah-Hartman return -ENOTTY; 255196fd7ce5SGreg Kroah-Hartman pid = tty_get_pgrp(real_tty); 255296fd7ce5SGreg Kroah-Hartman ret = put_user(pid_vnr(pid), p); 255396fd7ce5SGreg Kroah-Hartman put_pid(pid); 255496fd7ce5SGreg Kroah-Hartman return ret; 255596fd7ce5SGreg Kroah-Hartman } 255696fd7ce5SGreg Kroah-Hartman 255796fd7ce5SGreg Kroah-Hartman /** 255896fd7ce5SGreg Kroah-Hartman * tiocspgrp - attempt to set process group 255996fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 256096fd7ce5SGreg Kroah-Hartman * @real_tty: tty side device matching tty passed by user 256196fd7ce5SGreg Kroah-Hartman * @p: pid pointer 256296fd7ce5SGreg Kroah-Hartman * 256396fd7ce5SGreg Kroah-Hartman * Set the process group of the tty to the session passed. Only 256496fd7ce5SGreg Kroah-Hartman * permitted where the tty session is our session. 256596fd7ce5SGreg Kroah-Hartman * 256696fd7ce5SGreg Kroah-Hartman * Locking: RCU, ctrl lock 256796fd7ce5SGreg Kroah-Hartman */ 256896fd7ce5SGreg Kroah-Hartman 256996fd7ce5SGreg Kroah-Hartman static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 257096fd7ce5SGreg Kroah-Hartman { 257196fd7ce5SGreg Kroah-Hartman struct pid *pgrp; 257296fd7ce5SGreg Kroah-Hartman pid_t pgrp_nr; 257396fd7ce5SGreg Kroah-Hartman int retval = tty_check_change(real_tty); 257496fd7ce5SGreg Kroah-Hartman unsigned long flags; 257596fd7ce5SGreg Kroah-Hartman 257696fd7ce5SGreg Kroah-Hartman if (retval == -EIO) 257796fd7ce5SGreg Kroah-Hartman return -ENOTTY; 257896fd7ce5SGreg Kroah-Hartman if (retval) 257996fd7ce5SGreg Kroah-Hartman return retval; 258096fd7ce5SGreg Kroah-Hartman if (!current->signal->tty || 258196fd7ce5SGreg Kroah-Hartman (current->signal->tty != real_tty) || 258296fd7ce5SGreg Kroah-Hartman (real_tty->session != task_session(current))) 258396fd7ce5SGreg Kroah-Hartman return -ENOTTY; 258496fd7ce5SGreg Kroah-Hartman if (get_user(pgrp_nr, p)) 258596fd7ce5SGreg Kroah-Hartman return -EFAULT; 258696fd7ce5SGreg Kroah-Hartman if (pgrp_nr < 0) 258796fd7ce5SGreg Kroah-Hartman return -EINVAL; 258896fd7ce5SGreg Kroah-Hartman rcu_read_lock(); 258996fd7ce5SGreg Kroah-Hartman pgrp = find_vpid(pgrp_nr); 259096fd7ce5SGreg Kroah-Hartman retval = -ESRCH; 259196fd7ce5SGreg Kroah-Hartman if (!pgrp) 259296fd7ce5SGreg Kroah-Hartman goto out_unlock; 259396fd7ce5SGreg Kroah-Hartman retval = -EPERM; 259496fd7ce5SGreg Kroah-Hartman if (session_of_pgrp(pgrp) != task_session(current)) 259596fd7ce5SGreg Kroah-Hartman goto out_unlock; 259696fd7ce5SGreg Kroah-Hartman retval = 0; 259796fd7ce5SGreg Kroah-Hartman spin_lock_irqsave(&tty->ctrl_lock, flags); 259896fd7ce5SGreg Kroah-Hartman put_pid(real_tty->pgrp); 259996fd7ce5SGreg Kroah-Hartman real_tty->pgrp = get_pid(pgrp); 260096fd7ce5SGreg Kroah-Hartman spin_unlock_irqrestore(&tty->ctrl_lock, flags); 260196fd7ce5SGreg Kroah-Hartman out_unlock: 260296fd7ce5SGreg Kroah-Hartman rcu_read_unlock(); 260396fd7ce5SGreg Kroah-Hartman return retval; 260496fd7ce5SGreg Kroah-Hartman } 260596fd7ce5SGreg Kroah-Hartman 260696fd7ce5SGreg Kroah-Hartman /** 260796fd7ce5SGreg Kroah-Hartman * tiocgsid - get session id 260896fd7ce5SGreg Kroah-Hartman * @tty: tty passed by user 260925985edcSLucas De Marchi * @real_tty: tty side of the tty passed by the user if a pty else the tty 261096fd7ce5SGreg Kroah-Hartman * @p: pointer to returned session id 261196fd7ce5SGreg Kroah-Hartman * 261296fd7ce5SGreg Kroah-Hartman * Obtain the session id of the tty. If there is no session 261396fd7ce5SGreg Kroah-Hartman * return an error. 261496fd7ce5SGreg Kroah-Hartman * 261596fd7ce5SGreg Kroah-Hartman * Locking: none. Reference to current->signal->tty is safe. 261696fd7ce5SGreg Kroah-Hartman */ 261796fd7ce5SGreg Kroah-Hartman 261896fd7ce5SGreg Kroah-Hartman static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) 261996fd7ce5SGreg Kroah-Hartman { 262096fd7ce5SGreg Kroah-Hartman /* 262196fd7ce5SGreg Kroah-Hartman * (tty == real_tty) is a cheap way of 262296fd7ce5SGreg Kroah-Hartman * testing if the tty is NOT a master pty. 262396fd7ce5SGreg Kroah-Hartman */ 262496fd7ce5SGreg Kroah-Hartman if (tty == real_tty && current->signal->tty != real_tty) 262596fd7ce5SGreg Kroah-Hartman return -ENOTTY; 262696fd7ce5SGreg Kroah-Hartman if (!real_tty->session) 262796fd7ce5SGreg Kroah-Hartman return -ENOTTY; 262896fd7ce5SGreg Kroah-Hartman return put_user(pid_vnr(real_tty->session), p); 262996fd7ce5SGreg Kroah-Hartman } 263096fd7ce5SGreg Kroah-Hartman 263196fd7ce5SGreg Kroah-Hartman /** 263296fd7ce5SGreg Kroah-Hartman * tiocsetd - set line discipline 263396fd7ce5SGreg Kroah-Hartman * @tty: tty device 263496fd7ce5SGreg Kroah-Hartman * @p: pointer to user data 263596fd7ce5SGreg Kroah-Hartman * 263696fd7ce5SGreg Kroah-Hartman * Set the line discipline according to user request. 263796fd7ce5SGreg Kroah-Hartman * 263896fd7ce5SGreg Kroah-Hartman * Locking: see tty_set_ldisc, this function is just a helper 263996fd7ce5SGreg Kroah-Hartman */ 264096fd7ce5SGreg Kroah-Hartman 264196fd7ce5SGreg Kroah-Hartman static int tiocsetd(struct tty_struct *tty, int __user *p) 264296fd7ce5SGreg Kroah-Hartman { 264396fd7ce5SGreg Kroah-Hartman int ldisc; 264496fd7ce5SGreg Kroah-Hartman int ret; 264596fd7ce5SGreg Kroah-Hartman 264696fd7ce5SGreg Kroah-Hartman if (get_user(ldisc, p)) 264796fd7ce5SGreg Kroah-Hartman return -EFAULT; 264896fd7ce5SGreg Kroah-Hartman 264996fd7ce5SGreg Kroah-Hartman ret = tty_set_ldisc(tty, ldisc); 265096fd7ce5SGreg Kroah-Hartman 265196fd7ce5SGreg Kroah-Hartman return ret; 265296fd7ce5SGreg Kroah-Hartman } 265396fd7ce5SGreg Kroah-Hartman 265496fd7ce5SGreg Kroah-Hartman /** 265596fd7ce5SGreg Kroah-Hartman * send_break - performed time break 265696fd7ce5SGreg Kroah-Hartman * @tty: device to break on 265796fd7ce5SGreg Kroah-Hartman * @duration: timeout in mS 265896fd7ce5SGreg Kroah-Hartman * 265996fd7ce5SGreg Kroah-Hartman * Perform a timed break on hardware that lacks its own driver level 266096fd7ce5SGreg Kroah-Hartman * timed break functionality. 266196fd7ce5SGreg Kroah-Hartman * 266296fd7ce5SGreg Kroah-Hartman * Locking: 266396fd7ce5SGreg Kroah-Hartman * atomic_write_lock serializes 266496fd7ce5SGreg Kroah-Hartman * 266596fd7ce5SGreg Kroah-Hartman */ 266696fd7ce5SGreg Kroah-Hartman 266796fd7ce5SGreg Kroah-Hartman static int send_break(struct tty_struct *tty, unsigned int duration) 266896fd7ce5SGreg Kroah-Hartman { 266996fd7ce5SGreg Kroah-Hartman int retval; 267096fd7ce5SGreg Kroah-Hartman 267196fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl == NULL) 267296fd7ce5SGreg Kroah-Hartman return 0; 267396fd7ce5SGreg Kroah-Hartman 267496fd7ce5SGreg Kroah-Hartman if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) 267596fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, duration); 267696fd7ce5SGreg Kroah-Hartman else { 267796fd7ce5SGreg Kroah-Hartman /* Do the work ourselves */ 267896fd7ce5SGreg Kroah-Hartman if (tty_write_lock(tty, 0) < 0) 267996fd7ce5SGreg Kroah-Hartman return -EINTR; 268096fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, -1); 268196fd7ce5SGreg Kroah-Hartman if (retval) 268296fd7ce5SGreg Kroah-Hartman goto out; 268396fd7ce5SGreg Kroah-Hartman if (!signal_pending(current)) 268496fd7ce5SGreg Kroah-Hartman msleep_interruptible(duration); 268596fd7ce5SGreg Kroah-Hartman retval = tty->ops->break_ctl(tty, 0); 268696fd7ce5SGreg Kroah-Hartman out: 268796fd7ce5SGreg Kroah-Hartman tty_write_unlock(tty); 268896fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 268996fd7ce5SGreg Kroah-Hartman retval = -EINTR; 269096fd7ce5SGreg Kroah-Hartman } 269196fd7ce5SGreg Kroah-Hartman return retval; 269296fd7ce5SGreg Kroah-Hartman } 269396fd7ce5SGreg Kroah-Hartman 269496fd7ce5SGreg Kroah-Hartman /** 269596fd7ce5SGreg Kroah-Hartman * tty_tiocmget - get modem status 269696fd7ce5SGreg Kroah-Hartman * @tty: tty device 269796fd7ce5SGreg Kroah-Hartman * @file: user file pointer 269896fd7ce5SGreg Kroah-Hartman * @p: pointer to result 269996fd7ce5SGreg Kroah-Hartman * 270096fd7ce5SGreg Kroah-Hartman * Obtain the modem status bits from the tty driver if the feature 270196fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 270296fd7ce5SGreg Kroah-Hartman * 270396fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 270496fd7ce5SGreg Kroah-Hartman */ 270596fd7ce5SGreg Kroah-Hartman 270660b33c13SAlan Cox static int tty_tiocmget(struct tty_struct *tty, int __user *p) 270796fd7ce5SGreg Kroah-Hartman { 270896fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 270996fd7ce5SGreg Kroah-Hartman 271096fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmget) { 271160b33c13SAlan Cox retval = tty->ops->tiocmget(tty); 271296fd7ce5SGreg Kroah-Hartman 271396fd7ce5SGreg Kroah-Hartman if (retval >= 0) 271496fd7ce5SGreg Kroah-Hartman retval = put_user(retval, p); 271596fd7ce5SGreg Kroah-Hartman } 271696fd7ce5SGreg Kroah-Hartman return retval; 271796fd7ce5SGreg Kroah-Hartman } 271896fd7ce5SGreg Kroah-Hartman 271996fd7ce5SGreg Kroah-Hartman /** 272096fd7ce5SGreg Kroah-Hartman * tty_tiocmset - set modem status 272196fd7ce5SGreg Kroah-Hartman * @tty: tty device 272296fd7ce5SGreg Kroah-Hartman * @cmd: command - clear bits, set bits or set all 272396fd7ce5SGreg Kroah-Hartman * @p: pointer to desired bits 272496fd7ce5SGreg Kroah-Hartman * 272596fd7ce5SGreg Kroah-Hartman * Set the modem status bits from the tty driver if the feature 272696fd7ce5SGreg Kroah-Hartman * is supported. Return -EINVAL if it is not available. 272796fd7ce5SGreg Kroah-Hartman * 272896fd7ce5SGreg Kroah-Hartman * Locking: none (up to the driver) 272996fd7ce5SGreg Kroah-Hartman */ 273096fd7ce5SGreg Kroah-Hartman 273120b9d177SAlan Cox static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, 273296fd7ce5SGreg Kroah-Hartman unsigned __user *p) 273396fd7ce5SGreg Kroah-Hartman { 273496fd7ce5SGreg Kroah-Hartman int retval; 273596fd7ce5SGreg Kroah-Hartman unsigned int set, clear, val; 273696fd7ce5SGreg Kroah-Hartman 273796fd7ce5SGreg Kroah-Hartman if (tty->ops->tiocmset == NULL) 273896fd7ce5SGreg Kroah-Hartman return -EINVAL; 273996fd7ce5SGreg Kroah-Hartman 274096fd7ce5SGreg Kroah-Hartman retval = get_user(val, p); 274196fd7ce5SGreg Kroah-Hartman if (retval) 274296fd7ce5SGreg Kroah-Hartman return retval; 274396fd7ce5SGreg Kroah-Hartman set = clear = 0; 274496fd7ce5SGreg Kroah-Hartman switch (cmd) { 274596fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 274696fd7ce5SGreg Kroah-Hartman set = val; 274796fd7ce5SGreg Kroah-Hartman break; 274896fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 274996fd7ce5SGreg Kroah-Hartman clear = val; 275096fd7ce5SGreg Kroah-Hartman break; 275196fd7ce5SGreg Kroah-Hartman case TIOCMSET: 275296fd7ce5SGreg Kroah-Hartman set = val; 275396fd7ce5SGreg Kroah-Hartman clear = ~val; 275496fd7ce5SGreg Kroah-Hartman break; 275596fd7ce5SGreg Kroah-Hartman } 275696fd7ce5SGreg Kroah-Hartman set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 275796fd7ce5SGreg Kroah-Hartman clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; 275820b9d177SAlan Cox return tty->ops->tiocmset(tty, set, clear); 275996fd7ce5SGreg Kroah-Hartman } 276096fd7ce5SGreg Kroah-Hartman 276196fd7ce5SGreg Kroah-Hartman static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) 276296fd7ce5SGreg Kroah-Hartman { 276396fd7ce5SGreg Kroah-Hartman int retval = -EINVAL; 276496fd7ce5SGreg Kroah-Hartman struct serial_icounter_struct icount; 276596fd7ce5SGreg Kroah-Hartman memset(&icount, 0, sizeof(icount)); 276696fd7ce5SGreg Kroah-Hartman if (tty->ops->get_icount) 276796fd7ce5SGreg Kroah-Hartman retval = tty->ops->get_icount(tty, &icount); 276896fd7ce5SGreg Kroah-Hartman if (retval != 0) 276996fd7ce5SGreg Kroah-Hartman return retval; 277096fd7ce5SGreg Kroah-Hartman if (copy_to_user(arg, &icount, sizeof(icount))) 277196fd7ce5SGreg Kroah-Hartman return -EFAULT; 277296fd7ce5SGreg Kroah-Hartman return 0; 277396fd7ce5SGreg Kroah-Hartman } 277496fd7ce5SGreg Kroah-Hartman 27758a8ae62fSJiri Slaby static void tty_warn_deprecated_flags(struct serial_struct __user *ss) 27768a8ae62fSJiri Slaby { 27778a8ae62fSJiri Slaby static DEFINE_RATELIMIT_STATE(depr_flags, 27788a8ae62fSJiri Slaby DEFAULT_RATELIMIT_INTERVAL, 27798a8ae62fSJiri Slaby DEFAULT_RATELIMIT_BURST); 27808a8ae62fSJiri Slaby char comm[TASK_COMM_LEN]; 27818a8ae62fSJiri Slaby int flags; 27828a8ae62fSJiri Slaby 27838a8ae62fSJiri Slaby if (get_user(flags, &ss->flags)) 27848a8ae62fSJiri Slaby return; 27858a8ae62fSJiri Slaby 27868a8ae62fSJiri Slaby flags &= ASYNC_DEPRECATED; 27878a8ae62fSJiri Slaby 27888a8ae62fSJiri Slaby if (flags && __ratelimit(&depr_flags)) 27898a8ae62fSJiri Slaby pr_warning("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", 27908a8ae62fSJiri Slaby __func__, get_task_comm(comm, current), flags); 27918a8ae62fSJiri Slaby } 27928a8ae62fSJiri Slaby 27938f166e00SPeter Hurley /* 27948f166e00SPeter Hurley * if pty, return the slave side (real_tty) 27958f166e00SPeter Hurley * otherwise, return self 27968f166e00SPeter Hurley */ 27978f166e00SPeter Hurley static struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) 279896fd7ce5SGreg Kroah-Hartman { 279996fd7ce5SGreg Kroah-Hartman if (tty->driver->type == TTY_DRIVER_TYPE_PTY && 280096fd7ce5SGreg Kroah-Hartman tty->driver->subtype == PTY_TYPE_MASTER) 280196fd7ce5SGreg Kroah-Hartman tty = tty->link; 280296fd7ce5SGreg Kroah-Hartman return tty; 280396fd7ce5SGreg Kroah-Hartman } 280496fd7ce5SGreg Kroah-Hartman 280596fd7ce5SGreg Kroah-Hartman /* 280696fd7ce5SGreg Kroah-Hartman * Split this up, as gcc can choke on it otherwise.. 280796fd7ce5SGreg Kroah-Hartman */ 280896fd7ce5SGreg Kroah-Hartman long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 280996fd7ce5SGreg Kroah-Hartman { 281096fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 281196fd7ce5SGreg Kroah-Hartman struct tty_struct *real_tty; 281296fd7ce5SGreg Kroah-Hartman void __user *p = (void __user *)arg; 281396fd7ce5SGreg Kroah-Hartman int retval; 281496fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 281596fd7ce5SGreg Kroah-Hartman 28166131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 281796fd7ce5SGreg Kroah-Hartman return -EINVAL; 281896fd7ce5SGreg Kroah-Hartman 281996fd7ce5SGreg Kroah-Hartman real_tty = tty_pair_get_tty(tty); 282096fd7ce5SGreg Kroah-Hartman 282196fd7ce5SGreg Kroah-Hartman /* 282296fd7ce5SGreg Kroah-Hartman * Factor out some common prep work 282396fd7ce5SGreg Kroah-Hartman */ 282496fd7ce5SGreg Kroah-Hartman switch (cmd) { 282596fd7ce5SGreg Kroah-Hartman case TIOCSETD: 282696fd7ce5SGreg Kroah-Hartman case TIOCSBRK: 282796fd7ce5SGreg Kroah-Hartman case TIOCCBRK: 282896fd7ce5SGreg Kroah-Hartman case TCSBRK: 282996fd7ce5SGreg Kroah-Hartman case TCSBRKP: 283096fd7ce5SGreg Kroah-Hartman retval = tty_check_change(tty); 283196fd7ce5SGreg Kroah-Hartman if (retval) 283296fd7ce5SGreg Kroah-Hartman return retval; 283396fd7ce5SGreg Kroah-Hartman if (cmd != TIOCCBRK) { 283496fd7ce5SGreg Kroah-Hartman tty_wait_until_sent(tty, 0); 283596fd7ce5SGreg Kroah-Hartman if (signal_pending(current)) 283696fd7ce5SGreg Kroah-Hartman return -EINTR; 283796fd7ce5SGreg Kroah-Hartman } 283896fd7ce5SGreg Kroah-Hartman break; 283996fd7ce5SGreg Kroah-Hartman } 284096fd7ce5SGreg Kroah-Hartman 284196fd7ce5SGreg Kroah-Hartman /* 284296fd7ce5SGreg Kroah-Hartman * Now do the stuff. 284396fd7ce5SGreg Kroah-Hartman */ 284496fd7ce5SGreg Kroah-Hartman switch (cmd) { 284596fd7ce5SGreg Kroah-Hartman case TIOCSTI: 284696fd7ce5SGreg Kroah-Hartman return tiocsti(tty, p); 284796fd7ce5SGreg Kroah-Hartman case TIOCGWINSZ: 284896fd7ce5SGreg Kroah-Hartman return tiocgwinsz(real_tty, p); 284996fd7ce5SGreg Kroah-Hartman case TIOCSWINSZ: 285096fd7ce5SGreg Kroah-Hartman return tiocswinsz(real_tty, p); 285196fd7ce5SGreg Kroah-Hartman case TIOCCONS: 285296fd7ce5SGreg Kroah-Hartman return real_tty != tty ? -EINVAL : tioccons(file); 285396fd7ce5SGreg Kroah-Hartman case FIONBIO: 285496fd7ce5SGreg Kroah-Hartman return fionbio(file, p); 285596fd7ce5SGreg Kroah-Hartman case TIOCEXCL: 285696fd7ce5SGreg Kroah-Hartman set_bit(TTY_EXCLUSIVE, &tty->flags); 285796fd7ce5SGreg Kroah-Hartman return 0; 285896fd7ce5SGreg Kroah-Hartman case TIOCNXCL: 285996fd7ce5SGreg Kroah-Hartman clear_bit(TTY_EXCLUSIVE, &tty->flags); 286096fd7ce5SGreg Kroah-Hartman return 0; 286184fd7bdfSCyrill Gorcunov case TIOCGEXCL: 286284fd7bdfSCyrill Gorcunov { 286384fd7bdfSCyrill Gorcunov int excl = test_bit(TTY_EXCLUSIVE, &tty->flags); 286484fd7bdfSCyrill Gorcunov return put_user(excl, (int __user *)p); 286584fd7bdfSCyrill Gorcunov } 286696fd7ce5SGreg Kroah-Hartman case TIOCNOTTY: 286796fd7ce5SGreg Kroah-Hartman if (current->signal->tty != tty) 286896fd7ce5SGreg Kroah-Hartman return -ENOTTY; 286996fd7ce5SGreg Kroah-Hartman no_tty(); 287096fd7ce5SGreg Kroah-Hartman return 0; 287196fd7ce5SGreg Kroah-Hartman case TIOCSCTTY: 28720c556271SJann Horn return tiocsctty(tty, file, arg); 287396fd7ce5SGreg Kroah-Hartman case TIOCGPGRP: 287496fd7ce5SGreg Kroah-Hartman return tiocgpgrp(tty, real_tty, p); 287596fd7ce5SGreg Kroah-Hartman case TIOCSPGRP: 287696fd7ce5SGreg Kroah-Hartman return tiocspgrp(tty, real_tty, p); 287796fd7ce5SGreg Kroah-Hartman case TIOCGSID: 287896fd7ce5SGreg Kroah-Hartman return tiocgsid(tty, real_tty, p); 287996fd7ce5SGreg Kroah-Hartman case TIOCGETD: 288096fd7ce5SGreg Kroah-Hartman return put_user(tty->ldisc->ops->num, (int __user *)p); 288196fd7ce5SGreg Kroah-Hartman case TIOCSETD: 288296fd7ce5SGreg Kroah-Hartman return tiocsetd(tty, p); 28833c95c985SKay Sievers case TIOCVHANGUP: 28843c95c985SKay Sievers if (!capable(CAP_SYS_ADMIN)) 28853c95c985SKay Sievers return -EPERM; 28863c95c985SKay Sievers tty_vhangup(tty); 28873c95c985SKay Sievers return 0; 2888b7b8de08SWerner Fink case TIOCGDEV: 2889b7b8de08SWerner Fink { 2890b7b8de08SWerner Fink unsigned int ret = new_encode_dev(tty_devnum(real_tty)); 2891b7b8de08SWerner Fink return put_user(ret, (unsigned int __user *)p); 2892b7b8de08SWerner Fink } 289396fd7ce5SGreg Kroah-Hartman /* 289496fd7ce5SGreg Kroah-Hartman * Break handling 289596fd7ce5SGreg Kroah-Hartman */ 289696fd7ce5SGreg Kroah-Hartman case TIOCSBRK: /* Turn break on, unconditionally */ 289796fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 289896fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, -1); 289996fd7ce5SGreg Kroah-Hartman return 0; 290096fd7ce5SGreg Kroah-Hartman case TIOCCBRK: /* Turn break off, unconditionally */ 290196fd7ce5SGreg Kroah-Hartman if (tty->ops->break_ctl) 290296fd7ce5SGreg Kroah-Hartman return tty->ops->break_ctl(tty, 0); 290396fd7ce5SGreg Kroah-Hartman return 0; 290496fd7ce5SGreg Kroah-Hartman case TCSBRK: /* SVID version: non-zero arg --> no break */ 290596fd7ce5SGreg Kroah-Hartman /* non-zero arg means wait for all output data 290696fd7ce5SGreg Kroah-Hartman * to be sent (performed above) but don't send break. 290796fd7ce5SGreg Kroah-Hartman * This is used by the tcdrain() termios function. 290896fd7ce5SGreg Kroah-Hartman */ 290996fd7ce5SGreg Kroah-Hartman if (!arg) 291096fd7ce5SGreg Kroah-Hartman return send_break(tty, 250); 291196fd7ce5SGreg Kroah-Hartman return 0; 291296fd7ce5SGreg Kroah-Hartman case TCSBRKP: /* support for POSIX tcsendbreak() */ 291396fd7ce5SGreg Kroah-Hartman return send_break(tty, arg ? arg*100 : 250); 291496fd7ce5SGreg Kroah-Hartman 291596fd7ce5SGreg Kroah-Hartman case TIOCMGET: 291660b33c13SAlan Cox return tty_tiocmget(tty, p); 291796fd7ce5SGreg Kroah-Hartman case TIOCMSET: 291896fd7ce5SGreg Kroah-Hartman case TIOCMBIC: 291996fd7ce5SGreg Kroah-Hartman case TIOCMBIS: 292020b9d177SAlan Cox return tty_tiocmset(tty, cmd, p); 292196fd7ce5SGreg Kroah-Hartman case TIOCGICOUNT: 292296fd7ce5SGreg Kroah-Hartman retval = tty_tiocgicount(tty, p); 292396fd7ce5SGreg Kroah-Hartman /* For the moment allow fall through to the old method */ 292496fd7ce5SGreg Kroah-Hartman if (retval != -EINVAL) 292596fd7ce5SGreg Kroah-Hartman return retval; 292696fd7ce5SGreg Kroah-Hartman break; 292796fd7ce5SGreg Kroah-Hartman case TCFLSH: 292896fd7ce5SGreg Kroah-Hartman switch (arg) { 292996fd7ce5SGreg Kroah-Hartman case TCIFLUSH: 293096fd7ce5SGreg Kroah-Hartman case TCIOFLUSH: 293196fd7ce5SGreg Kroah-Hartman /* flush tty buffer and allow ldisc to process ioctl */ 293286c80a8eSPeter Hurley tty_buffer_flush(tty, NULL); 293396fd7ce5SGreg Kroah-Hartman break; 293496fd7ce5SGreg Kroah-Hartman } 293596fd7ce5SGreg Kroah-Hartman break; 29368a8ae62fSJiri Slaby case TIOCSSERIAL: 29378a8ae62fSJiri Slaby tty_warn_deprecated_flags(p); 29388a8ae62fSJiri Slaby break; 293996fd7ce5SGreg Kroah-Hartman } 294096fd7ce5SGreg Kroah-Hartman if (tty->ops->ioctl) { 2941c961bfb1SPeter Hurley retval = tty->ops->ioctl(tty, cmd, arg); 294296fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 294396fd7ce5SGreg Kroah-Hartman return retval; 294496fd7ce5SGreg Kroah-Hartman } 294596fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 294696fd7ce5SGreg Kroah-Hartman retval = -EINVAL; 294796fd7ce5SGreg Kroah-Hartman if (ld->ops->ioctl) { 294896fd7ce5SGreg Kroah-Hartman retval = ld->ops->ioctl(tty, file, cmd, arg); 294996fd7ce5SGreg Kroah-Hartman if (retval == -ENOIOCTLCMD) 2950bbb63c51SWanlong Gao retval = -ENOTTY; 295196fd7ce5SGreg Kroah-Hartman } 295296fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 295396fd7ce5SGreg Kroah-Hartman return retval; 295496fd7ce5SGreg Kroah-Hartman } 295596fd7ce5SGreg Kroah-Hartman 295696fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_COMPAT 295796fd7ce5SGreg Kroah-Hartman static long tty_compat_ioctl(struct file *file, unsigned int cmd, 295896fd7ce5SGreg Kroah-Hartman unsigned long arg) 295996fd7ce5SGreg Kroah-Hartman { 296096fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = file_tty(file); 296196fd7ce5SGreg Kroah-Hartman struct tty_ldisc *ld; 296296fd7ce5SGreg Kroah-Hartman int retval = -ENOIOCTLCMD; 296396fd7ce5SGreg Kroah-Hartman 29646131ffaaSAl Viro if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) 296596fd7ce5SGreg Kroah-Hartman return -EINVAL; 296696fd7ce5SGreg Kroah-Hartman 296796fd7ce5SGreg Kroah-Hartman if (tty->ops->compat_ioctl) { 2968c961bfb1SPeter Hurley retval = tty->ops->compat_ioctl(tty, cmd, arg); 296996fd7ce5SGreg Kroah-Hartman if (retval != -ENOIOCTLCMD) 297096fd7ce5SGreg Kroah-Hartman return retval; 297196fd7ce5SGreg Kroah-Hartman } 297296fd7ce5SGreg Kroah-Hartman 297396fd7ce5SGreg Kroah-Hartman ld = tty_ldisc_ref_wait(tty); 297496fd7ce5SGreg Kroah-Hartman if (ld->ops->compat_ioctl) 297596fd7ce5SGreg Kroah-Hartman retval = ld->ops->compat_ioctl(tty, file, cmd, arg); 29768193c429SThomas Meyer else 29778193c429SThomas Meyer retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg); 297896fd7ce5SGreg Kroah-Hartman tty_ldisc_deref(ld); 297996fd7ce5SGreg Kroah-Hartman 298096fd7ce5SGreg Kroah-Hartman return retval; 298196fd7ce5SGreg Kroah-Hartman } 298296fd7ce5SGreg Kroah-Hartman #endif 298396fd7ce5SGreg Kroah-Hartman 2984c3c073f8SAl Viro static int this_tty(const void *t, struct file *file, unsigned fd) 2985c3c073f8SAl Viro { 2986c3c073f8SAl Viro if (likely(file->f_op->read != tty_read)) 2987c3c073f8SAl Viro return 0; 2988c3c073f8SAl Viro return file_tty(file) != t ? 0 : fd + 1; 2989c3c073f8SAl Viro } 2990c3c073f8SAl Viro 299196fd7ce5SGreg Kroah-Hartman /* 299296fd7ce5SGreg Kroah-Hartman * This implements the "Secure Attention Key" --- the idea is to 299396fd7ce5SGreg Kroah-Hartman * prevent trojan horses by killing all processes associated with this 299496fd7ce5SGreg Kroah-Hartman * tty when the user hits the "Secure Attention Key". Required for 299596fd7ce5SGreg Kroah-Hartman * super-paranoid applications --- see the Orange Book for more details. 299696fd7ce5SGreg Kroah-Hartman * 299796fd7ce5SGreg Kroah-Hartman * This code could be nicer; ideally it should send a HUP, wait a few 299896fd7ce5SGreg Kroah-Hartman * seconds, then send a INT, and then a KILL signal. But you then 299996fd7ce5SGreg Kroah-Hartman * have to coordinate with the init process, since all processes associated 300096fd7ce5SGreg Kroah-Hartman * with the current tty must be dead before the new getty is allowed 300196fd7ce5SGreg Kroah-Hartman * to spawn. 300296fd7ce5SGreg Kroah-Hartman * 300396fd7ce5SGreg Kroah-Hartman * Now, if it would be correct ;-/ The current code has a nasty hole - 300496fd7ce5SGreg Kroah-Hartman * it doesn't catch files in flight. We may send the descriptor to ourselves 300596fd7ce5SGreg Kroah-Hartman * via AF_UNIX socket, close it and later fetch from socket. FIXME. 300696fd7ce5SGreg Kroah-Hartman * 300796fd7ce5SGreg Kroah-Hartman * Nasty bug: do_SAK is being called in interrupt context. This can 300896fd7ce5SGreg Kroah-Hartman * deadlock. We punt it up to process context. AKPM - 16Mar2001 300996fd7ce5SGreg Kroah-Hartman */ 301096fd7ce5SGreg Kroah-Hartman void __do_SAK(struct tty_struct *tty) 301196fd7ce5SGreg Kroah-Hartman { 301296fd7ce5SGreg Kroah-Hartman #ifdef TTY_SOFT_SAK 301396fd7ce5SGreg Kroah-Hartman tty_hangup(tty); 301496fd7ce5SGreg Kroah-Hartman #else 301596fd7ce5SGreg Kroah-Hartman struct task_struct *g, *p; 301696fd7ce5SGreg Kroah-Hartman struct pid *session; 301796fd7ce5SGreg Kroah-Hartman int i; 301896fd7ce5SGreg Kroah-Hartman 301996fd7ce5SGreg Kroah-Hartman if (!tty) 302096fd7ce5SGreg Kroah-Hartman return; 302196fd7ce5SGreg Kroah-Hartman session = tty->session; 302296fd7ce5SGreg Kroah-Hartman 302396fd7ce5SGreg Kroah-Hartman tty_ldisc_flush(tty); 302496fd7ce5SGreg Kroah-Hartman 302596fd7ce5SGreg Kroah-Hartman tty_driver_flush_buffer(tty); 302696fd7ce5SGreg Kroah-Hartman 302796fd7ce5SGreg Kroah-Hartman read_lock(&tasklist_lock); 302896fd7ce5SGreg Kroah-Hartman /* Kill the entire session */ 302996fd7ce5SGreg Kroah-Hartman do_each_pid_task(session, PIDTYPE_SID, p) { 303096fd7ce5SGreg Kroah-Hartman printk(KERN_NOTICE "SAK: killed process %d" 303196fd7ce5SGreg Kroah-Hartman " (%s): task_session(p)==tty->session\n", 303296fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 303396fd7ce5SGreg Kroah-Hartman send_sig(SIGKILL, p, 1); 303496fd7ce5SGreg Kroah-Hartman } while_each_pid_task(session, PIDTYPE_SID, p); 303596fd7ce5SGreg Kroah-Hartman /* Now kill any processes that happen to have the 303696fd7ce5SGreg Kroah-Hartman * tty open. 303796fd7ce5SGreg Kroah-Hartman */ 303896fd7ce5SGreg Kroah-Hartman do_each_thread(g, p) { 303996fd7ce5SGreg Kroah-Hartman if (p->signal->tty == tty) { 304096fd7ce5SGreg Kroah-Hartman printk(KERN_NOTICE "SAK: killed process %d" 304196fd7ce5SGreg Kroah-Hartman " (%s): task_session(p)==tty->session\n", 304296fd7ce5SGreg Kroah-Hartman task_pid_nr(p), p->comm); 304396fd7ce5SGreg Kroah-Hartman send_sig(SIGKILL, p, 1); 304496fd7ce5SGreg Kroah-Hartman continue; 304596fd7ce5SGreg Kroah-Hartman } 304696fd7ce5SGreg Kroah-Hartman task_lock(p); 3047c3c073f8SAl Viro i = iterate_fd(p->files, 0, this_tty, tty); 3048c3c073f8SAl Viro if (i != 0) { 304996fd7ce5SGreg Kroah-Hartman printk(KERN_NOTICE "SAK: killed process %d" 305096fd7ce5SGreg Kroah-Hartman " (%s): fd#%d opened to the tty\n", 3051c3c073f8SAl Viro task_pid_nr(p), p->comm, i - 1); 305296fd7ce5SGreg Kroah-Hartman force_sig(SIGKILL, p); 305396fd7ce5SGreg Kroah-Hartman } 305496fd7ce5SGreg Kroah-Hartman task_unlock(p); 305596fd7ce5SGreg Kroah-Hartman } while_each_thread(g, p); 305696fd7ce5SGreg Kroah-Hartman read_unlock(&tasklist_lock); 305796fd7ce5SGreg Kroah-Hartman #endif 305896fd7ce5SGreg Kroah-Hartman } 305996fd7ce5SGreg Kroah-Hartman 306096fd7ce5SGreg Kroah-Hartman static void do_SAK_work(struct work_struct *work) 306196fd7ce5SGreg Kroah-Hartman { 306296fd7ce5SGreg Kroah-Hartman struct tty_struct *tty = 306396fd7ce5SGreg Kroah-Hartman container_of(work, struct tty_struct, SAK_work); 306496fd7ce5SGreg Kroah-Hartman __do_SAK(tty); 306596fd7ce5SGreg Kroah-Hartman } 306696fd7ce5SGreg Kroah-Hartman 306796fd7ce5SGreg Kroah-Hartman /* 306896fd7ce5SGreg Kroah-Hartman * The tq handling here is a little racy - tty->SAK_work may already be queued. 306996fd7ce5SGreg Kroah-Hartman * Fortunately we don't need to worry, because if ->SAK_work is already queued, 307096fd7ce5SGreg Kroah-Hartman * the values which we write to it will be identical to the values which it 307196fd7ce5SGreg Kroah-Hartman * already has. --akpm 307296fd7ce5SGreg Kroah-Hartman */ 307396fd7ce5SGreg Kroah-Hartman void do_SAK(struct tty_struct *tty) 307496fd7ce5SGreg Kroah-Hartman { 307596fd7ce5SGreg Kroah-Hartman if (!tty) 307696fd7ce5SGreg Kroah-Hartman return; 307796fd7ce5SGreg Kroah-Hartman schedule_work(&tty->SAK_work); 307896fd7ce5SGreg Kroah-Hartman } 307996fd7ce5SGreg Kroah-Hartman 308096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(do_SAK); 308196fd7ce5SGreg Kroah-Hartman 30826e9430acSGreg Kroah-Hartman static int dev_match_devt(struct device *dev, const void *data) 308396fd7ce5SGreg Kroah-Hartman { 30846e9430acSGreg Kroah-Hartman const dev_t *devt = data; 308596fd7ce5SGreg Kroah-Hartman return dev->devt == *devt; 308696fd7ce5SGreg Kroah-Hartman } 308796fd7ce5SGreg Kroah-Hartman 308896fd7ce5SGreg Kroah-Hartman /* Must put_device() after it's unused! */ 308996fd7ce5SGreg Kroah-Hartman static struct device *tty_get_device(struct tty_struct *tty) 309096fd7ce5SGreg Kroah-Hartman { 309196fd7ce5SGreg Kroah-Hartman dev_t devt = tty_devnum(tty); 309296fd7ce5SGreg Kroah-Hartman return class_find_device(tty_class, NULL, &devt, dev_match_devt); 309396fd7ce5SGreg Kroah-Hartman } 309496fd7ce5SGreg Kroah-Hartman 309596fd7ce5SGreg Kroah-Hartman 309696fd7ce5SGreg Kroah-Hartman /** 30972c964a2fSRasmus Villemoes * alloc_tty_struct 309896fd7ce5SGreg Kroah-Hartman * 30992c964a2fSRasmus Villemoes * This subroutine allocates and initializes a tty structure. 310096fd7ce5SGreg Kroah-Hartman * 31012c964a2fSRasmus Villemoes * Locking: none - tty in question is not exposed at this point 310296fd7ce5SGreg Kroah-Hartman */ 310396fd7ce5SGreg Kroah-Hartman 31042c964a2fSRasmus Villemoes struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx) 310596fd7ce5SGreg Kroah-Hartman { 31062c964a2fSRasmus Villemoes struct tty_struct *tty; 31072c964a2fSRasmus Villemoes 31082c964a2fSRasmus Villemoes tty = kzalloc(sizeof(*tty), GFP_KERNEL); 31092c964a2fSRasmus Villemoes if (!tty) 31102c964a2fSRasmus Villemoes return NULL; 31112c964a2fSRasmus Villemoes 311296fd7ce5SGreg Kroah-Hartman kref_init(&tty->kref); 311396fd7ce5SGreg Kroah-Hartman tty->magic = TTY_MAGIC; 311496fd7ce5SGreg Kroah-Hartman tty_ldisc_init(tty); 311596fd7ce5SGreg Kroah-Hartman tty->session = NULL; 311696fd7ce5SGreg Kroah-Hartman tty->pgrp = NULL; 311789c8d91eSAlan Cox mutex_init(&tty->legacy_mutex); 3118d8c1f929SPeter Hurley mutex_init(&tty->throttle_mutex); 31196a1c0680SPeter Hurley init_rwsem(&tty->termios_rwsem); 3120dee4a0beSPeter Hurley mutex_init(&tty->winsize_mutex); 312136697529SPeter Hurley init_ldsem(&tty->ldisc_sem); 312296fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->write_wait); 312396fd7ce5SGreg Kroah-Hartman init_waitqueue_head(&tty->read_wait); 312496fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->hangup_work, do_tty_hangup); 312596fd7ce5SGreg Kroah-Hartman mutex_init(&tty->atomic_write_lock); 312696fd7ce5SGreg Kroah-Hartman spin_lock_init(&tty->ctrl_lock); 3127f9e053dcSPeter Hurley spin_lock_init(&tty->flow_lock); 312896fd7ce5SGreg Kroah-Hartman INIT_LIST_HEAD(&tty->tty_files); 312996fd7ce5SGreg Kroah-Hartman INIT_WORK(&tty->SAK_work, do_SAK_work); 313096fd7ce5SGreg Kroah-Hartman 313196fd7ce5SGreg Kroah-Hartman tty->driver = driver; 313296fd7ce5SGreg Kroah-Hartman tty->ops = driver->ops; 313396fd7ce5SGreg Kroah-Hartman tty->index = idx; 313496fd7ce5SGreg Kroah-Hartman tty_line_name(driver, idx, tty->name); 313596fd7ce5SGreg Kroah-Hartman tty->dev = tty_get_device(tty); 31362c964a2fSRasmus Villemoes 31372c964a2fSRasmus Villemoes return tty; 313896fd7ce5SGreg Kroah-Hartman } 313996fd7ce5SGreg Kroah-Hartman 314096fd7ce5SGreg Kroah-Hartman /** 31416716671dSJiri Slaby * deinitialize_tty_struct 31426716671dSJiri Slaby * @tty: tty to deinitialize 31436716671dSJiri Slaby * 31446716671dSJiri Slaby * This subroutine deinitializes a tty structure that has been newly 31456716671dSJiri Slaby * allocated but tty_release cannot be called on that yet. 31466716671dSJiri Slaby * 31476716671dSJiri Slaby * Locking: none - tty in question must not be exposed at this point 31486716671dSJiri Slaby */ 31496716671dSJiri Slaby void deinitialize_tty_struct(struct tty_struct *tty) 31506716671dSJiri Slaby { 31516716671dSJiri Slaby tty_ldisc_deinit(tty); 31526716671dSJiri Slaby } 31536716671dSJiri Slaby 31546716671dSJiri Slaby /** 315596fd7ce5SGreg Kroah-Hartman * tty_put_char - write one character to a tty 315696fd7ce5SGreg Kroah-Hartman * @tty: tty 315796fd7ce5SGreg Kroah-Hartman * @ch: character 315896fd7ce5SGreg Kroah-Hartman * 315996fd7ce5SGreg Kroah-Hartman * Write one byte to the tty using the provided put_char method 316096fd7ce5SGreg Kroah-Hartman * if present. Returns the number of characters successfully output. 316196fd7ce5SGreg Kroah-Hartman * 316296fd7ce5SGreg Kroah-Hartman * Note: the specific put_char operation in the driver layer may go 316396fd7ce5SGreg Kroah-Hartman * away soon. Don't call it directly, use this method 316496fd7ce5SGreg Kroah-Hartman */ 316596fd7ce5SGreg Kroah-Hartman 316696fd7ce5SGreg Kroah-Hartman int tty_put_char(struct tty_struct *tty, unsigned char ch) 316796fd7ce5SGreg Kroah-Hartman { 316896fd7ce5SGreg Kroah-Hartman if (tty->ops->put_char) 316996fd7ce5SGreg Kroah-Hartman return tty->ops->put_char(tty, ch); 317096fd7ce5SGreg Kroah-Hartman return tty->ops->write(tty, &ch, 1); 317196fd7ce5SGreg Kroah-Hartman } 317296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL_GPL(tty_put_char); 317396fd7ce5SGreg Kroah-Hartman 317496fd7ce5SGreg Kroah-Hartman struct class *tty_class; 317596fd7ce5SGreg Kroah-Hartman 31767e73eca6SJiri Slaby static int tty_cdev_add(struct tty_driver *driver, dev_t dev, 31777e73eca6SJiri Slaby unsigned int index, unsigned int count) 31787e73eca6SJiri Slaby { 3179c1a752baSLeon Yu int err; 3180c1a752baSLeon Yu 31817e73eca6SJiri Slaby /* init here, since reused cdevs cause crashes */ 3182a3a10ce3SRichard Watts driver->cdevs[index] = cdev_alloc(); 3183a3a10ce3SRichard Watts if (!driver->cdevs[index]) 3184a3a10ce3SRichard Watts return -ENOMEM; 3185c1a752baSLeon Yu driver->cdevs[index]->ops = &tty_fops; 3186a3a10ce3SRichard Watts driver->cdevs[index]->owner = driver->owner; 3187c1a752baSLeon Yu err = cdev_add(driver->cdevs[index], dev, count); 3188c1a752baSLeon Yu if (err) 3189c1a752baSLeon Yu kobject_put(&driver->cdevs[index]->kobj); 3190c1a752baSLeon Yu return err; 31917e73eca6SJiri Slaby } 31927e73eca6SJiri Slaby 319396fd7ce5SGreg Kroah-Hartman /** 319496fd7ce5SGreg Kroah-Hartman * tty_register_device - register a tty device 319596fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 319696fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 319796fd7ce5SGreg Kroah-Hartman * @device: a struct device that is associated with this tty device. 319896fd7ce5SGreg Kroah-Hartman * This field is optional, if there is no known struct device 319996fd7ce5SGreg Kroah-Hartman * for this tty device it can be set to NULL safely. 320096fd7ce5SGreg Kroah-Hartman * 320196fd7ce5SGreg Kroah-Hartman * Returns a pointer to the struct device for this tty device 320296fd7ce5SGreg Kroah-Hartman * (or ERR_PTR(-EFOO) on error). 320396fd7ce5SGreg Kroah-Hartman * 320496fd7ce5SGreg Kroah-Hartman * This call is required to be made to register an individual tty device 320596fd7ce5SGreg Kroah-Hartman * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 320696fd7ce5SGreg Kroah-Hartman * that bit is not set, this function should not be called by a tty 320796fd7ce5SGreg Kroah-Hartman * driver. 320896fd7ce5SGreg Kroah-Hartman * 320996fd7ce5SGreg Kroah-Hartman * Locking: ?? 321096fd7ce5SGreg Kroah-Hartman */ 321196fd7ce5SGreg Kroah-Hartman 321296fd7ce5SGreg Kroah-Hartman struct device *tty_register_device(struct tty_driver *driver, unsigned index, 321396fd7ce5SGreg Kroah-Hartman struct device *device) 321496fd7ce5SGreg Kroah-Hartman { 32156915c0e4STomas Hlavacek return tty_register_device_attr(driver, index, device, NULL, NULL); 32166915c0e4STomas Hlavacek } 32176915c0e4STomas Hlavacek EXPORT_SYMBOL(tty_register_device); 32186915c0e4STomas Hlavacek 3219b1b79916STomas Hlavacek static void tty_device_create_release(struct device *dev) 3220b1b79916STomas Hlavacek { 3221b1b79916STomas Hlavacek pr_debug("device: '%s': %s\n", dev_name(dev), __func__); 3222b1b79916STomas Hlavacek kfree(dev); 3223b1b79916STomas Hlavacek } 3224b1b79916STomas Hlavacek 32256915c0e4STomas Hlavacek /** 32266915c0e4STomas Hlavacek * tty_register_device_attr - register a tty device 32276915c0e4STomas Hlavacek * @driver: the tty driver that describes the tty device 32286915c0e4STomas Hlavacek * @index: the index in the tty driver for this tty device 32296915c0e4STomas Hlavacek * @device: a struct device that is associated with this tty device. 32306915c0e4STomas Hlavacek * This field is optional, if there is no known struct device 32316915c0e4STomas Hlavacek * for this tty device it can be set to NULL safely. 32326915c0e4STomas Hlavacek * @drvdata: Driver data to be set to device. 32336915c0e4STomas Hlavacek * @attr_grp: Attribute group to be set on device. 32346915c0e4STomas Hlavacek * 32356915c0e4STomas Hlavacek * Returns a pointer to the struct device for this tty device 32366915c0e4STomas Hlavacek * (or ERR_PTR(-EFOO) on error). 32376915c0e4STomas Hlavacek * 32386915c0e4STomas Hlavacek * This call is required to be made to register an individual tty device 32396915c0e4STomas Hlavacek * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If 32406915c0e4STomas Hlavacek * that bit is not set, this function should not be called by a tty 32416915c0e4STomas Hlavacek * driver. 32426915c0e4STomas Hlavacek * 32436915c0e4STomas Hlavacek * Locking: ?? 32446915c0e4STomas Hlavacek */ 32456915c0e4STomas Hlavacek struct device *tty_register_device_attr(struct tty_driver *driver, 32466915c0e4STomas Hlavacek unsigned index, struct device *device, 32476915c0e4STomas Hlavacek void *drvdata, 32486915c0e4STomas Hlavacek const struct attribute_group **attr_grp) 32496915c0e4STomas Hlavacek { 325096fd7ce5SGreg Kroah-Hartman char name[64]; 32516915c0e4STomas Hlavacek dev_t devt = MKDEV(driver->major, driver->minor_start) + index; 32526915c0e4STomas Hlavacek struct device *dev = NULL; 32536915c0e4STomas Hlavacek int retval = -ENODEV; 32547e73eca6SJiri Slaby bool cdev = false; 325596fd7ce5SGreg Kroah-Hartman 325696fd7ce5SGreg Kroah-Hartman if (index >= driver->num) { 325796fd7ce5SGreg Kroah-Hartman printk(KERN_ERR "Attempt to register invalid tty line number " 325896fd7ce5SGreg Kroah-Hartman " (%d).\n", index); 325996fd7ce5SGreg Kroah-Hartman return ERR_PTR(-EINVAL); 326096fd7ce5SGreg Kroah-Hartman } 326196fd7ce5SGreg Kroah-Hartman 326296fd7ce5SGreg Kroah-Hartman if (driver->type == TTY_DRIVER_TYPE_PTY) 326396fd7ce5SGreg Kroah-Hartman pty_line_name(driver, index, name); 326496fd7ce5SGreg Kroah-Hartman else 326596fd7ce5SGreg Kroah-Hartman tty_line_name(driver, index, name); 326696fd7ce5SGreg Kroah-Hartman 32677e73eca6SJiri Slaby if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 32686915c0e4STomas Hlavacek retval = tty_cdev_add(driver, devt, index, 1); 32696915c0e4STomas Hlavacek if (retval) 32706915c0e4STomas Hlavacek goto error; 32717e73eca6SJiri Slaby cdev = true; 32727e73eca6SJiri Slaby } 32737e73eca6SJiri Slaby 32746915c0e4STomas Hlavacek dev = kzalloc(sizeof(*dev), GFP_KERNEL); 32756915c0e4STomas Hlavacek if (!dev) { 32766915c0e4STomas Hlavacek retval = -ENOMEM; 32776915c0e4STomas Hlavacek goto error; 327896fd7ce5SGreg Kroah-Hartman } 32796915c0e4STomas Hlavacek 32806915c0e4STomas Hlavacek dev->devt = devt; 32816915c0e4STomas Hlavacek dev->class = tty_class; 32826915c0e4STomas Hlavacek dev->parent = device; 3283b1b79916STomas Hlavacek dev->release = tty_device_create_release; 32846915c0e4STomas Hlavacek dev_set_name(dev, "%s", name); 32856915c0e4STomas Hlavacek dev->groups = attr_grp; 32866915c0e4STomas Hlavacek dev_set_drvdata(dev, drvdata); 32876915c0e4STomas Hlavacek 32886915c0e4STomas Hlavacek retval = device_register(dev); 32896915c0e4STomas Hlavacek if (retval) 32906915c0e4STomas Hlavacek goto error; 32916915c0e4STomas Hlavacek 32926915c0e4STomas Hlavacek return dev; 32936915c0e4STomas Hlavacek 32946915c0e4STomas Hlavacek error: 32956915c0e4STomas Hlavacek put_device(dev); 3296a3a10ce3SRichard Watts if (cdev) { 3297a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3298a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3299a3a10ce3SRichard Watts } 33006915c0e4STomas Hlavacek return ERR_PTR(retval); 33016915c0e4STomas Hlavacek } 33026915c0e4STomas Hlavacek EXPORT_SYMBOL_GPL(tty_register_device_attr); 330396fd7ce5SGreg Kroah-Hartman 330496fd7ce5SGreg Kroah-Hartman /** 330596fd7ce5SGreg Kroah-Hartman * tty_unregister_device - unregister a tty device 330696fd7ce5SGreg Kroah-Hartman * @driver: the tty driver that describes the tty device 330796fd7ce5SGreg Kroah-Hartman * @index: the index in the tty driver for this tty device 330896fd7ce5SGreg Kroah-Hartman * 330996fd7ce5SGreg Kroah-Hartman * If a tty device is registered with a call to tty_register_device() then 331096fd7ce5SGreg Kroah-Hartman * this function must be called when the tty device is gone. 331196fd7ce5SGreg Kroah-Hartman * 331296fd7ce5SGreg Kroah-Hartman * Locking: ?? 331396fd7ce5SGreg Kroah-Hartman */ 331496fd7ce5SGreg Kroah-Hartman 331596fd7ce5SGreg Kroah-Hartman void tty_unregister_device(struct tty_driver *driver, unsigned index) 331696fd7ce5SGreg Kroah-Hartman { 331796fd7ce5SGreg Kroah-Hartman device_destroy(tty_class, 331896fd7ce5SGreg Kroah-Hartman MKDEV(driver->major, driver->minor_start) + index); 3319a3a10ce3SRichard Watts if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 3320a3a10ce3SRichard Watts cdev_del(driver->cdevs[index]); 3321a3a10ce3SRichard Watts driver->cdevs[index] = NULL; 3322a3a10ce3SRichard Watts } 332396fd7ce5SGreg Kroah-Hartman } 332496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_device); 332596fd7ce5SGreg Kroah-Hartman 33267f0bc6a6SJiri Slaby /** 33277f0bc6a6SJiri Slaby * __tty_alloc_driver -- allocate tty driver 33287f0bc6a6SJiri Slaby * @lines: count of lines this driver can handle at most 33297f0bc6a6SJiri Slaby * @owner: module which is repsonsible for this driver 33307f0bc6a6SJiri Slaby * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags 33317f0bc6a6SJiri Slaby * 33327f0bc6a6SJiri Slaby * This should not be called directly, some of the provided macros should be 33337f0bc6a6SJiri Slaby * used instead. Use IS_ERR and friends on @retval. 33347f0bc6a6SJiri Slaby */ 33357f0bc6a6SJiri Slaby struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner, 33367f0bc6a6SJiri Slaby unsigned long flags) 333796fd7ce5SGreg Kroah-Hartman { 333896fd7ce5SGreg Kroah-Hartman struct tty_driver *driver; 33397e73eca6SJiri Slaby unsigned int cdevs = 1; 334016a02081SJiri Slaby int err; 334196fd7ce5SGreg Kroah-Hartman 33420019b408SJiri Slaby if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1)) 33437f0bc6a6SJiri Slaby return ERR_PTR(-EINVAL); 33447f0bc6a6SJiri Slaby 334596fd7ce5SGreg Kroah-Hartman driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); 33467f0bc6a6SJiri Slaby if (!driver) 33477f0bc6a6SJiri Slaby return ERR_PTR(-ENOMEM); 33487f0bc6a6SJiri Slaby 334996fd7ce5SGreg Kroah-Hartman kref_init(&driver->kref); 335096fd7ce5SGreg Kroah-Hartman driver->magic = TTY_DRIVER_MAGIC; 335196fd7ce5SGreg Kroah-Hartman driver->num = lines; 33521a54a76dSJiri Slaby driver->owner = owner; 33537f0bc6a6SJiri Slaby driver->flags = flags; 335416a02081SJiri Slaby 335516a02081SJiri Slaby if (!(flags & TTY_DRIVER_DEVPTS_MEM)) { 335616a02081SJiri Slaby driver->ttys = kcalloc(lines, sizeof(*driver->ttys), 335716a02081SJiri Slaby GFP_KERNEL); 335816a02081SJiri Slaby driver->termios = kcalloc(lines, sizeof(*driver->termios), 335916a02081SJiri Slaby GFP_KERNEL); 336016a02081SJiri Slaby if (!driver->ttys || !driver->termios) { 336116a02081SJiri Slaby err = -ENOMEM; 336216a02081SJiri Slaby goto err_free_all; 336316a02081SJiri Slaby } 336416a02081SJiri Slaby } 336516a02081SJiri Slaby 336616a02081SJiri Slaby if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) { 336716a02081SJiri Slaby driver->ports = kcalloc(lines, sizeof(*driver->ports), 336816a02081SJiri Slaby GFP_KERNEL); 336916a02081SJiri Slaby if (!driver->ports) { 337016a02081SJiri Slaby err = -ENOMEM; 337116a02081SJiri Slaby goto err_free_all; 337216a02081SJiri Slaby } 33737e73eca6SJiri Slaby cdevs = lines; 33747e73eca6SJiri Slaby } 33757e73eca6SJiri Slaby 33767e73eca6SJiri Slaby driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL); 33777e73eca6SJiri Slaby if (!driver->cdevs) { 33787e73eca6SJiri Slaby err = -ENOMEM; 33797e73eca6SJiri Slaby goto err_free_all; 338016a02081SJiri Slaby } 33817f0bc6a6SJiri Slaby 338296fd7ce5SGreg Kroah-Hartman return driver; 338316a02081SJiri Slaby err_free_all: 338416a02081SJiri Slaby kfree(driver->ports); 338516a02081SJiri Slaby kfree(driver->ttys); 338616a02081SJiri Slaby kfree(driver->termios); 3387a3a10ce3SRichard Watts kfree(driver->cdevs); 338816a02081SJiri Slaby kfree(driver); 338916a02081SJiri Slaby return ERR_PTR(err); 339096fd7ce5SGreg Kroah-Hartman } 33917f0bc6a6SJiri Slaby EXPORT_SYMBOL(__tty_alloc_driver); 339296fd7ce5SGreg Kroah-Hartman 339396fd7ce5SGreg Kroah-Hartman static void destruct_tty_driver(struct kref *kref) 339496fd7ce5SGreg Kroah-Hartman { 339596fd7ce5SGreg Kroah-Hartman struct tty_driver *driver = container_of(kref, struct tty_driver, kref); 339696fd7ce5SGreg Kroah-Hartman int i; 339796fd7ce5SGreg Kroah-Hartman struct ktermios *tp; 339896fd7ce5SGreg Kroah-Hartman 339996fd7ce5SGreg Kroah-Hartman if (driver->flags & TTY_DRIVER_INSTALLED) { 340096fd7ce5SGreg Kroah-Hartman /* 340196fd7ce5SGreg Kroah-Hartman * Free the termios and termios_locked structures because 340296fd7ce5SGreg Kroah-Hartman * we don't want to get memory leaks when modular tty 340396fd7ce5SGreg Kroah-Hartman * drivers are removed from the kernel. 340496fd7ce5SGreg Kroah-Hartman */ 340596fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 340696fd7ce5SGreg Kroah-Hartman tp = driver->termios[i]; 340796fd7ce5SGreg Kroah-Hartman if (tp) { 340896fd7ce5SGreg Kroah-Hartman driver->termios[i] = NULL; 340996fd7ce5SGreg Kroah-Hartman kfree(tp); 341096fd7ce5SGreg Kroah-Hartman } 341196fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) 341296fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 341396fd7ce5SGreg Kroah-Hartman } 341496fd7ce5SGreg Kroah-Hartman proc_tty_unregister_driver(driver); 34157e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) 3416a3a10ce3SRichard Watts cdev_del(driver->cdevs[0]); 341796fd7ce5SGreg Kroah-Hartman } 34187e73eca6SJiri Slaby kfree(driver->cdevs); 341904831dc1SJiri Slaby kfree(driver->ports); 342016a02081SJiri Slaby kfree(driver->termios); 342116a02081SJiri Slaby kfree(driver->ttys); 342296fd7ce5SGreg Kroah-Hartman kfree(driver); 342396fd7ce5SGreg Kroah-Hartman } 342496fd7ce5SGreg Kroah-Hartman 342596fd7ce5SGreg Kroah-Hartman void tty_driver_kref_put(struct tty_driver *driver) 342696fd7ce5SGreg Kroah-Hartman { 342796fd7ce5SGreg Kroah-Hartman kref_put(&driver->kref, destruct_tty_driver); 342896fd7ce5SGreg Kroah-Hartman } 342996fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_driver_kref_put); 343096fd7ce5SGreg Kroah-Hartman 343196fd7ce5SGreg Kroah-Hartman void tty_set_operations(struct tty_driver *driver, 343296fd7ce5SGreg Kroah-Hartman const struct tty_operations *op) 343396fd7ce5SGreg Kroah-Hartman { 343496fd7ce5SGreg Kroah-Hartman driver->ops = op; 343596fd7ce5SGreg Kroah-Hartman }; 343696fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_set_operations); 343796fd7ce5SGreg Kroah-Hartman 343896fd7ce5SGreg Kroah-Hartman void put_tty_driver(struct tty_driver *d) 343996fd7ce5SGreg Kroah-Hartman { 344096fd7ce5SGreg Kroah-Hartman tty_driver_kref_put(d); 344196fd7ce5SGreg Kroah-Hartman } 344296fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(put_tty_driver); 344396fd7ce5SGreg Kroah-Hartman 344496fd7ce5SGreg Kroah-Hartman /* 344596fd7ce5SGreg Kroah-Hartman * Called by a tty driver to register itself. 344696fd7ce5SGreg Kroah-Hartman */ 344796fd7ce5SGreg Kroah-Hartman int tty_register_driver(struct tty_driver *driver) 344896fd7ce5SGreg Kroah-Hartman { 344996fd7ce5SGreg Kroah-Hartman int error; 345096fd7ce5SGreg Kroah-Hartman int i; 345196fd7ce5SGreg Kroah-Hartman dev_t dev; 345296fd7ce5SGreg Kroah-Hartman struct device *d; 345396fd7ce5SGreg Kroah-Hartman 345496fd7ce5SGreg Kroah-Hartman if (!driver->major) { 345596fd7ce5SGreg Kroah-Hartman error = alloc_chrdev_region(&dev, driver->minor_start, 345696fd7ce5SGreg Kroah-Hartman driver->num, driver->name); 345796fd7ce5SGreg Kroah-Hartman if (!error) { 345896fd7ce5SGreg Kroah-Hartman driver->major = MAJOR(dev); 345996fd7ce5SGreg Kroah-Hartman driver->minor_start = MINOR(dev); 346096fd7ce5SGreg Kroah-Hartman } 346196fd7ce5SGreg Kroah-Hartman } else { 346296fd7ce5SGreg Kroah-Hartman dev = MKDEV(driver->major, driver->minor_start); 346396fd7ce5SGreg Kroah-Hartman error = register_chrdev_region(dev, driver->num, driver->name); 346496fd7ce5SGreg Kroah-Hartman } 34659bb8a3d4SJiri Slaby if (error < 0) 346616a02081SJiri Slaby goto err; 346796fd7ce5SGreg Kroah-Hartman 34687e73eca6SJiri Slaby if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) { 34697e73eca6SJiri Slaby error = tty_cdev_add(driver, dev, 0, driver->num); 34709bb8a3d4SJiri Slaby if (error) 34719bb8a3d4SJiri Slaby goto err_unreg_char; 34727e73eca6SJiri Slaby } 347396fd7ce5SGreg Kroah-Hartman 347496fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 347596fd7ce5SGreg Kroah-Hartman list_add(&driver->tty_drivers, &tty_drivers); 347696fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 347796fd7ce5SGreg Kroah-Hartman 347896fd7ce5SGreg Kroah-Hartman if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { 347996fd7ce5SGreg Kroah-Hartman for (i = 0; i < driver->num; i++) { 348096fd7ce5SGreg Kroah-Hartman d = tty_register_device(driver, i, NULL); 348196fd7ce5SGreg Kroah-Hartman if (IS_ERR(d)) { 348296fd7ce5SGreg Kroah-Hartman error = PTR_ERR(d); 348316a02081SJiri Slaby goto err_unreg_devs; 348496fd7ce5SGreg Kroah-Hartman } 348596fd7ce5SGreg Kroah-Hartman } 348696fd7ce5SGreg Kroah-Hartman } 348796fd7ce5SGreg Kroah-Hartman proc_tty_register_driver(driver); 348896fd7ce5SGreg Kroah-Hartman driver->flags |= TTY_DRIVER_INSTALLED; 348996fd7ce5SGreg Kroah-Hartman return 0; 349096fd7ce5SGreg Kroah-Hartman 349116a02081SJiri Slaby err_unreg_devs: 349296fd7ce5SGreg Kroah-Hartman for (i--; i >= 0; i--) 349396fd7ce5SGreg Kroah-Hartman tty_unregister_device(driver, i); 349496fd7ce5SGreg Kroah-Hartman 349596fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 349696fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 349796fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 349896fd7ce5SGreg Kroah-Hartman 34999bb8a3d4SJiri Slaby err_unreg_char: 350096fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(dev, driver->num); 350116a02081SJiri Slaby err: 350296fd7ce5SGreg Kroah-Hartman return error; 350396fd7ce5SGreg Kroah-Hartman } 350496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_register_driver); 350596fd7ce5SGreg Kroah-Hartman 350696fd7ce5SGreg Kroah-Hartman /* 350796fd7ce5SGreg Kroah-Hartman * Called by a tty driver to unregister itself. 350896fd7ce5SGreg Kroah-Hartman */ 350996fd7ce5SGreg Kroah-Hartman int tty_unregister_driver(struct tty_driver *driver) 351096fd7ce5SGreg Kroah-Hartman { 351196fd7ce5SGreg Kroah-Hartman #if 0 351296fd7ce5SGreg Kroah-Hartman /* FIXME */ 351396fd7ce5SGreg Kroah-Hartman if (driver->refcount) 351496fd7ce5SGreg Kroah-Hartman return -EBUSY; 351596fd7ce5SGreg Kroah-Hartman #endif 351696fd7ce5SGreg Kroah-Hartman unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), 351796fd7ce5SGreg Kroah-Hartman driver->num); 351896fd7ce5SGreg Kroah-Hartman mutex_lock(&tty_mutex); 351996fd7ce5SGreg Kroah-Hartman list_del(&driver->tty_drivers); 352096fd7ce5SGreg Kroah-Hartman mutex_unlock(&tty_mutex); 352196fd7ce5SGreg Kroah-Hartman return 0; 352296fd7ce5SGreg Kroah-Hartman } 352396fd7ce5SGreg Kroah-Hartman 352496fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_unregister_driver); 352596fd7ce5SGreg Kroah-Hartman 352696fd7ce5SGreg Kroah-Hartman dev_t tty_devnum(struct tty_struct *tty) 352796fd7ce5SGreg Kroah-Hartman { 352896fd7ce5SGreg Kroah-Hartman return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; 352996fd7ce5SGreg Kroah-Hartman } 353096fd7ce5SGreg Kroah-Hartman EXPORT_SYMBOL(tty_devnum); 353196fd7ce5SGreg Kroah-Hartman 353296fd7ce5SGreg Kroah-Hartman void tty_default_fops(struct file_operations *fops) 353396fd7ce5SGreg Kroah-Hartman { 353496fd7ce5SGreg Kroah-Hartman *fops = tty_fops; 353596fd7ce5SGreg Kroah-Hartman } 353696fd7ce5SGreg Kroah-Hartman 353796fd7ce5SGreg Kroah-Hartman /* 353896fd7ce5SGreg Kroah-Hartman * Initialize the console device. This is called *early*, so 353996fd7ce5SGreg Kroah-Hartman * we can't necessarily depend on lots of kernel help here. 354096fd7ce5SGreg Kroah-Hartman * Just do some early initializations, and do the complex setup 354196fd7ce5SGreg Kroah-Hartman * later. 354296fd7ce5SGreg Kroah-Hartman */ 354396fd7ce5SGreg Kroah-Hartman void __init console_init(void) 354496fd7ce5SGreg Kroah-Hartman { 354596fd7ce5SGreg Kroah-Hartman initcall_t *call; 354696fd7ce5SGreg Kroah-Hartman 354796fd7ce5SGreg Kroah-Hartman /* Setup the default TTY line discipline. */ 354896fd7ce5SGreg Kroah-Hartman tty_ldisc_begin(); 354996fd7ce5SGreg Kroah-Hartman 355096fd7ce5SGreg Kroah-Hartman /* 355196fd7ce5SGreg Kroah-Hartman * set up the console device so that later boot sequences can 355296fd7ce5SGreg Kroah-Hartman * inform about problems etc.. 355396fd7ce5SGreg Kroah-Hartman */ 355496fd7ce5SGreg Kroah-Hartman call = __con_initcall_start; 355596fd7ce5SGreg Kroah-Hartman while (call < __con_initcall_end) { 355696fd7ce5SGreg Kroah-Hartman (*call)(); 355796fd7ce5SGreg Kroah-Hartman call++; 355896fd7ce5SGreg Kroah-Hartman } 355996fd7ce5SGreg Kroah-Hartman } 356096fd7ce5SGreg Kroah-Hartman 35612c9ede55SAl Viro static char *tty_devnode(struct device *dev, umode_t *mode) 356296fd7ce5SGreg Kroah-Hartman { 356396fd7ce5SGreg Kroah-Hartman if (!mode) 356496fd7ce5SGreg Kroah-Hartman return NULL; 356596fd7ce5SGreg Kroah-Hartman if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || 356696fd7ce5SGreg Kroah-Hartman dev->devt == MKDEV(TTYAUX_MAJOR, 2)) 356796fd7ce5SGreg Kroah-Hartman *mode = 0666; 356896fd7ce5SGreg Kroah-Hartman return NULL; 356996fd7ce5SGreg Kroah-Hartman } 357096fd7ce5SGreg Kroah-Hartman 357196fd7ce5SGreg Kroah-Hartman static int __init tty_class_init(void) 357296fd7ce5SGreg Kroah-Hartman { 357396fd7ce5SGreg Kroah-Hartman tty_class = class_create(THIS_MODULE, "tty"); 357496fd7ce5SGreg Kroah-Hartman if (IS_ERR(tty_class)) 357596fd7ce5SGreg Kroah-Hartman return PTR_ERR(tty_class); 357696fd7ce5SGreg Kroah-Hartman tty_class->devnode = tty_devnode; 357796fd7ce5SGreg Kroah-Hartman return 0; 357896fd7ce5SGreg Kroah-Hartman } 357996fd7ce5SGreg Kroah-Hartman 358096fd7ce5SGreg Kroah-Hartman postcore_initcall(tty_class_init); 358196fd7ce5SGreg Kroah-Hartman 358296fd7ce5SGreg Kroah-Hartman /* 3/2004 jmc: why do these devices exist? */ 358396fd7ce5SGreg Kroah-Hartman static struct cdev tty_cdev, console_cdev; 358496fd7ce5SGreg Kroah-Hartman 3585fbc92a34SKay Sievers static ssize_t show_cons_active(struct device *dev, 3586fbc92a34SKay Sievers struct device_attribute *attr, char *buf) 3587fbc92a34SKay Sievers { 3588fbc92a34SKay Sievers struct console *cs[16]; 3589fbc92a34SKay Sievers int i = 0; 3590fbc92a34SKay Sievers struct console *c; 3591fbc92a34SKay Sievers ssize_t count = 0; 3592fbc92a34SKay Sievers 3593ac751efaSTorben Hohn console_lock(); 3594a2a6a822SKay Sievers for_each_console(c) { 3595fbc92a34SKay Sievers if (!c->device) 3596fbc92a34SKay Sievers continue; 3597fbc92a34SKay Sievers if (!c->write) 3598fbc92a34SKay Sievers continue; 3599fbc92a34SKay Sievers if ((c->flags & CON_ENABLED) == 0) 3600fbc92a34SKay Sievers continue; 3601fbc92a34SKay Sievers cs[i++] = c; 3602fbc92a34SKay Sievers if (i >= ARRAY_SIZE(cs)) 3603fbc92a34SKay Sievers break; 3604fbc92a34SKay Sievers } 3605723abd87SHannes Reinecke while (i--) { 3606723abd87SHannes Reinecke int index = cs[i]->index; 3607723abd87SHannes Reinecke struct tty_driver *drv = cs[i]->device(cs[i], &index); 3608723abd87SHannes Reinecke 3609723abd87SHannes Reinecke /* don't resolve tty0 as some programs depend on it */ 3610723abd87SHannes Reinecke if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR)) 3611723abd87SHannes Reinecke count += tty_line_name(drv, index, buf + count); 3612723abd87SHannes Reinecke else 3613723abd87SHannes Reinecke count += sprintf(buf + count, "%s%d", 3614723abd87SHannes Reinecke cs[i]->name, cs[i]->index); 3615723abd87SHannes Reinecke 3616723abd87SHannes Reinecke count += sprintf(buf + count, "%c", i ? ' ':'\n'); 3617723abd87SHannes Reinecke } 3618ac751efaSTorben Hohn console_unlock(); 3619fbc92a34SKay Sievers 3620fbc92a34SKay Sievers return count; 3621fbc92a34SKay Sievers } 3622fbc92a34SKay Sievers static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL); 3623fbc92a34SKay Sievers 36241083a7beSTakashi Iwai static struct attribute *cons_dev_attrs[] = { 36251083a7beSTakashi Iwai &dev_attr_active.attr, 36261083a7beSTakashi Iwai NULL 36271083a7beSTakashi Iwai }; 36281083a7beSTakashi Iwai 36291083a7beSTakashi Iwai ATTRIBUTE_GROUPS(cons_dev); 36301083a7beSTakashi Iwai 3631fbc92a34SKay Sievers static struct device *consdev; 3632fbc92a34SKay Sievers 3633fbc92a34SKay Sievers void console_sysfs_notify(void) 3634fbc92a34SKay Sievers { 3635fbc92a34SKay Sievers if (consdev) 3636fbc92a34SKay Sievers sysfs_notify(&consdev->kobj, NULL, "active"); 3637fbc92a34SKay Sievers } 3638fbc92a34SKay Sievers 363996fd7ce5SGreg Kroah-Hartman /* 364096fd7ce5SGreg Kroah-Hartman * Ok, now we can initialize the rest of the tty devices and can count 364196fd7ce5SGreg Kroah-Hartman * on memory allocations, interrupts etc.. 364296fd7ce5SGreg Kroah-Hartman */ 364396fd7ce5SGreg Kroah-Hartman int __init tty_init(void) 364496fd7ce5SGreg Kroah-Hartman { 364596fd7ce5SGreg Kroah-Hartman cdev_init(&tty_cdev, &tty_fops); 364696fd7ce5SGreg Kroah-Hartman if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || 364796fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) 364896fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/tty driver\n"); 3649fbc92a34SKay Sievers device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty"); 365096fd7ce5SGreg Kroah-Hartman 365196fd7ce5SGreg Kroah-Hartman cdev_init(&console_cdev, &console_fops); 365296fd7ce5SGreg Kroah-Hartman if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || 365396fd7ce5SGreg Kroah-Hartman register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) 365496fd7ce5SGreg Kroah-Hartman panic("Couldn't register /dev/console driver\n"); 36551083a7beSTakashi Iwai consdev = device_create_with_groups(tty_class, NULL, 36561083a7beSTakashi Iwai MKDEV(TTYAUX_MAJOR, 1), NULL, 36571083a7beSTakashi Iwai cons_dev_groups, "console"); 3658fbc92a34SKay Sievers if (IS_ERR(consdev)) 3659fbc92a34SKay Sievers consdev = NULL; 366096fd7ce5SGreg Kroah-Hartman 366196fd7ce5SGreg Kroah-Hartman #ifdef CONFIG_VT 366296fd7ce5SGreg Kroah-Hartman vty_init(&console_fops); 366396fd7ce5SGreg Kroah-Hartman #endif 366496fd7ce5SGreg Kroah-Hartman return 0; 366596fd7ce5SGreg Kroah-Hartman } 366696fd7ce5SGreg Kroah-Hartman 3667