Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 3 | */ |
| 4 | |
| 5 | /* |
| 6 | * 'tty_io.c' gives an orthogonal feeling to tty's, be they consoles |
| 7 | * or rs-channels. It also implements echoing, cooked mode etc. |
| 8 | * |
| 9 | * Kill-line thanks to John T Kohl, who also corrected VMIN = VTIME = 0. |
| 10 | * |
| 11 | * Modified by Theodore Ts'o, 9/14/92, to dynamically allocate the |
| 12 | * tty_struct and tty_queue structures. Previously there was an array |
| 13 | * of 256 tty_struct's which was statically allocated, and the |
| 14 | * tty_queue structures were allocated at boot time. Both are now |
| 15 | * dynamically allocated only when the tty is open. |
| 16 | * |
| 17 | * Also restructured routines so that there is more of a separation |
| 18 | * between the high-level tty routines (tty_io.c and tty_ioctl.c) and |
| 19 | * the low-level tty routines (serial.c, pty.c, console.c). This |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 20 | * makes for cleaner and more compact code. -TYT, 9/17/92 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | * |
| 22 | * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines |
| 23 | * which can be dynamically activated and de-activated by the line |
| 24 | * discipline handling modules (like SLIP). |
| 25 | * |
| 26 | * NOTE: pay no attention to the line discipline code (yet); its |
| 27 | * interface is still subject to change in this version... |
| 28 | * -- TYT, 1/31/92 |
| 29 | * |
| 30 | * Added functionality to the OPOST tty handling. No delays, but all |
| 31 | * other bits should be there. |
| 32 | * -- Nick Holloway <alfie@dcs.warwick.ac.uk>, 27th May 1993. |
| 33 | * |
| 34 | * Rewrote canonical mode and added more termios flags. |
| 35 | * -- julian@uhunix.uhcc.hawaii.edu (J. Cowley), 13Jan94 |
| 36 | * |
| 37 | * Reorganized FASYNC support so mouse code can share it. |
| 38 | * -- ctm@ardi.com, 9Sep95 |
| 39 | * |
| 40 | * New TIOCLINUX variants added. |
| 41 | * -- mj@k332.feld.cvut.cz, 19-Nov-95 |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 42 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | * Restrict vt switching via ioctl() |
| 44 | * -- grif@cs.ucr.edu, 5-Dec-95 |
| 45 | * |
| 46 | * Move console and virtual terminal code to more appropriate files, |
| 47 | * implement CONFIG_VT and generalize console device interface. |
| 48 | * -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97 |
| 49 | * |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 50 | * Rewrote tty_init_dev and tty_release_dev to eliminate races. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | * -- Bill Hawes <whawes@star.net>, June 97 |
| 52 | * |
| 53 | * Added devfs support. |
| 54 | * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 13-Jan-1998 |
| 55 | * |
| 56 | * Added support for a Unix98-style ptmx device. |
| 57 | * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 |
| 58 | * |
| 59 | * Reduced memory usage for older ARM systems |
| 60 | * -- Russell King <rmk@arm.linux.org.uk> |
| 61 | * |
| 62 | * Move do_SAK() into process context. Less stack use in devfs functions. |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 63 | * alloc_tty_struct() always uses kmalloc() |
| 64 | * -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | */ |
| 66 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | #include <linux/types.h> |
| 68 | #include <linux/major.h> |
| 69 | #include <linux/errno.h> |
| 70 | #include <linux/signal.h> |
| 71 | #include <linux/fcntl.h> |
| 72 | #include <linux/sched.h> |
| 73 | #include <linux/interrupt.h> |
| 74 | #include <linux/tty.h> |
| 75 | #include <linux/tty_driver.h> |
| 76 | #include <linux/tty_flip.h> |
| 77 | #include <linux/devpts_fs.h> |
| 78 | #include <linux/file.h> |
Al Viro | 9f3acc3 | 2008-04-24 07:44:08 -0400 | [diff] [blame] | 79 | #include <linux/fdtable.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | #include <linux/console.h> |
| 81 | #include <linux/timer.h> |
| 82 | #include <linux/ctype.h> |
| 83 | #include <linux/kd.h> |
| 84 | #include <linux/mm.h> |
| 85 | #include <linux/string.h> |
| 86 | #include <linux/slab.h> |
| 87 | #include <linux/poll.h> |
| 88 | #include <linux/proc_fs.h> |
| 89 | #include <linux/init.h> |
| 90 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | #include <linux/device.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | #include <linux/wait.h> |
| 93 | #include <linux/bitops.h> |
Domen Puncer | b20f3ae | 2005-06-25 14:58:42 -0700 | [diff] [blame] | 94 | #include <linux/delay.h> |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 95 | #include <linux/seq_file.h> |
Alan Cox | d281da7 | 2010-09-16 18:21:24 +0100 | [diff] [blame] | 96 | #include <linux/serial.h> |
Manuel Zerpies | 5a3c6b2 | 2011-06-16 14:07:22 +0200 | [diff] [blame] | 97 | #include <linux/ratelimit.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 99 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | |
| 101 | #include <linux/kbd_kern.h> |
| 102 | #include <linux/vt_kern.h> |
| 103 | #include <linux/selection.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | |
| 105 | #include <linux/kmod.h> |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 106 | #include <linux/nsproxy.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | |
| 108 | #undef TTY_DEBUG_HANGUP |
Peter Hurley | accff79 | 2015-07-12 22:49:09 -0400 | [diff] [blame] | 109 | #ifdef TTY_DEBUG_HANGUP |
| 110 | # define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args) |
| 111 | #else |
| 112 | # define tty_debug_hangup(tty, f, args...) do { } while (0) |
| 113 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | |
| 115 | #define TTY_PARANOIA_CHECK 1 |
| 116 | #define CHECK_TTY_COUNT 1 |
| 117 | |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 118 | struct ktermios tty_std_termios = { /* for the benefit of tty drivers */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | .c_iflag = ICRNL | IXON, |
| 120 | .c_oflag = OPOST | ONLCR, |
| 121 | .c_cflag = B38400 | CS8 | CREAD | HUPCL, |
| 122 | .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | |
| 123 | ECHOCTL | ECHOKE | IEXTEN, |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 124 | .c_cc = INIT_C_CC, |
| 125 | .c_ispeed = 38400, |
Peter Hurley | 133b130 | 2016-01-10 22:41:07 -0800 | [diff] [blame] | 126 | .c_ospeed = 38400, |
| 127 | /* .c_line = N_TTY, */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | }; |
| 129 | |
| 130 | EXPORT_SYMBOL(tty_std_termios); |
| 131 | |
| 132 | /* This list gets poked at by procfs and various bits of boot up code. This |
| 133 | could do with some rationalisation such as pulling the tty proc function |
| 134 | into this file */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 135 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | LIST_HEAD(tty_drivers); /* linked list of tty drivers */ |
| 137 | |
Peter Hurley | d1d027e | 2016-01-09 21:35:18 -0800 | [diff] [blame] | 138 | /* Mutex to protect creating and releasing a tty */ |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 139 | DEFINE_MUTEX(tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); |
| 142 | static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 143 | ssize_t redirected_tty_write(struct file *, const char __user *, |
| 144 | size_t, loff_t *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | static unsigned int tty_poll(struct file *, poll_table *); |
| 146 | static int tty_open(struct inode *, struct file *); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 147 | long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 148 | #ifdef CONFIG_COMPAT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 149 | static long tty_compat_ioctl(struct file *file, unsigned int cmd, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 150 | unsigned long arg); |
| 151 | #else |
| 152 | #define tty_compat_ioctl NULL |
| 153 | #endif |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 154 | static int __tty_fasync(int fd, struct file *filp, int on); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 155 | static int tty_fasync(int fd, struct file *filp, int on); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 156 | static void release_tty(struct tty_struct *tty, int idx); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 158 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 159 | * free_tty_struct - free a disused tty |
| 160 | * @tty: tty struct to free |
| 161 | * |
| 162 | * Free the write buffers, tty queue and tty memory itself. |
| 163 | * |
| 164 | * Locking: none. Must be called after tty is definitely unused |
| 165 | */ |
| 166 | |
Peter Hurley | a3123fd | 2016-01-09 21:13:48 -0800 | [diff] [blame] | 167 | static void free_tty_struct(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | { |
Peter Hurley | c8b710b | 2016-01-09 21:13:46 -0800 | [diff] [blame] | 169 | tty_ldisc_deinit(tty); |
Markus Elfring | a211b1a | 2014-11-21 13:42:29 +0100 | [diff] [blame] | 170 | put_device(tty->dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | kfree(tty->write_buf); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 172 | tty->magic = 0xDEADDEAD; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | kfree(tty); |
| 174 | } |
| 175 | |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 176 | static inline struct tty_struct *file_tty(struct file *file) |
| 177 | { |
| 178 | return ((struct tty_file_private *)file->private_data)->tty; |
| 179 | } |
| 180 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 181 | int tty_alloc_file(struct file *file) |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 182 | { |
| 183 | struct tty_file_private *priv; |
| 184 | |
Pekka Enberg | f573bd1 | 2010-08-24 07:48:34 +0300 | [diff] [blame] | 185 | priv = kmalloc(sizeof(*priv), GFP_KERNEL); |
| 186 | if (!priv) |
| 187 | return -ENOMEM; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 188 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 189 | file->private_data = priv; |
| 190 | |
| 191 | return 0; |
| 192 | } |
| 193 | |
| 194 | /* Associate a new file with the tty structure */ |
| 195 | void tty_add_file(struct tty_struct *tty, struct file *file) |
| 196 | { |
| 197 | struct tty_file_private *priv = file->private_data; |
| 198 | |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 199 | priv->tty = tty; |
| 200 | priv->file = file; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 201 | |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 202 | spin_lock(&tty->files_lock); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 203 | list_add(&priv->list, &tty->tty_files); |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 204 | spin_unlock(&tty->files_lock); |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 205 | } |
Pekka Enberg | f573bd1 | 2010-08-24 07:48:34 +0300 | [diff] [blame] | 206 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 207 | /** |
| 208 | * tty_free_file - free file->private_data |
| 209 | * |
| 210 | * This shall be used only for fail path handling when tty_add_file was not |
| 211 | * called yet. |
| 212 | */ |
| 213 | void tty_free_file(struct file *file) |
| 214 | { |
| 215 | struct tty_file_private *priv = file->private_data; |
| 216 | |
| 217 | file->private_data = NULL; |
| 218 | kfree(priv); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 219 | } |
| 220 | |
| 221 | /* Delete file from its tty */ |
Josh Triplett | 2520e27 | 2012-11-18 21:27:47 -0800 | [diff] [blame] | 222 | static void tty_del_file(struct file *file) |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 223 | { |
| 224 | struct tty_file_private *priv = file->private_data; |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 225 | struct tty_struct *tty = priv->tty; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 226 | |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 227 | spin_lock(&tty->files_lock); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 228 | list_del(&priv->list); |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 229 | spin_unlock(&tty->files_lock); |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 230 | tty_free_file(file); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 231 | } |
| 232 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 233 | /** |
| 234 | * tty_name - return tty naming |
| 235 | * @tty: tty structure |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 236 | * |
| 237 | * Convert a tty structure into a name. The name reflects the kernel |
| 238 | * naming policy and if udev is in use may not reflect user space |
| 239 | * |
| 240 | * Locking: none |
| 241 | */ |
| 242 | |
Rasmus Villemoes | 429b474 | 2015-03-31 15:55:59 +0200 | [diff] [blame] | 243 | const char *tty_name(const struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | { |
| 245 | if (!tty) /* Hmm. NULL pointer. That's fun. */ |
Rasmus Villemoes | 917162c | 2015-03-31 15:55:58 +0200 | [diff] [blame] | 246 | return "NULL tty"; |
| 247 | return tty->name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | } |
| 249 | |
| 250 | EXPORT_SYMBOL(tty_name); |
| 251 | |
Peter Hurley | 0a083ed | 2015-11-08 13:01:12 -0500 | [diff] [blame] | 252 | const char *tty_driver_name(const struct tty_struct *tty) |
| 253 | { |
| 254 | if (!tty || !tty->driver) |
| 255 | return ""; |
| 256 | return tty->driver->name; |
| 257 | } |
| 258 | |
Peter Hurley | 82b8f88 | 2015-11-08 13:01:09 -0500 | [diff] [blame] | 259 | static int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | const char *routine) |
| 261 | { |
| 262 | #ifdef TTY_PARANOIA_CHECK |
| 263 | if (!tty) { |
Peter Hurley | 89222e6 | 2015-11-08 13:01:18 -0500 | [diff] [blame] | 264 | pr_warn("(%d:%d): %s: NULL tty\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | imajor(inode), iminor(inode), routine); |
| 266 | return 1; |
| 267 | } |
| 268 | if (tty->magic != TTY_MAGIC) { |
Peter Hurley | 89222e6 | 2015-11-08 13:01:18 -0500 | [diff] [blame] | 269 | pr_warn("(%d:%d): %s: bad magic number\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | imajor(inode), iminor(inode), routine); |
| 271 | return 1; |
| 272 | } |
| 273 | #endif |
| 274 | return 0; |
| 275 | } |
| 276 | |
Peter Hurley | deb287e | 2014-11-05 12:12:55 -0500 | [diff] [blame] | 277 | /* Caller must hold tty_lock */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 278 | static int check_tty_count(struct tty_struct *tty, const char *routine) |
| 279 | { |
| 280 | #ifdef CHECK_TTY_COUNT |
| 281 | struct list_head *p; |
| 282 | int count = 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 283 | |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 284 | spin_lock(&tty->files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | list_for_each(p, &tty->tty_files) { |
| 286 | count++; |
| 287 | } |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 288 | spin_unlock(&tty->files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 290 | tty->driver->subtype == PTY_TYPE_SLAVE && |
| 291 | tty->link && tty->link->count) |
| 292 | count++; |
| 293 | if (tty->count != count) { |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 294 | tty_warn(tty, "%s: tty->count(%d) != #fd's(%d)\n", |
| 295 | routine, tty->count, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | return count; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 297 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | #endif |
| 299 | return 0; |
| 300 | } |
| 301 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 302 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 303 | * get_tty_driver - find device of a tty |
| 304 | * @dev_t: device identifier |
| 305 | * @index: returns the index of the tty |
| 306 | * |
| 307 | * This routine returns a tty driver structure, given a device number |
| 308 | * and also passes back the index number. |
| 309 | * |
| 310 | * Locking: caller must hold tty_mutex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 312 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | static struct tty_driver *get_tty_driver(dev_t device, int *index) |
| 314 | { |
| 315 | struct tty_driver *p; |
| 316 | |
| 317 | list_for_each_entry(p, &tty_drivers, tty_drivers) { |
| 318 | dev_t base = MKDEV(p->major, p->minor_start); |
| 319 | if (device < base || device >= base + p->num) |
| 320 | continue; |
| 321 | *index = device - base; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 322 | return tty_driver_kref_get(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | } |
| 324 | return NULL; |
| 325 | } |
| 326 | |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 327 | #ifdef CONFIG_CONSOLE_POLL |
| 328 | |
| 329 | /** |
| 330 | * tty_find_polling_driver - find device of a polled tty |
| 331 | * @name: name string to match |
| 332 | * @line: pointer to resulting tty line nr |
| 333 | * |
| 334 | * This routine returns a tty driver structure, given a name |
| 335 | * and the condition that the tty driver is capable of polled |
| 336 | * operation. |
| 337 | */ |
| 338 | struct tty_driver *tty_find_polling_driver(char *name, int *line) |
| 339 | { |
| 340 | struct tty_driver *p, *res = NULL; |
| 341 | int tty_line = 0; |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 342 | int len; |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 343 | char *str, *stp; |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 344 | |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 345 | for (str = name; *str; str++) |
| 346 | if ((*str >= '0' && *str <= '9') || *str == ',') |
| 347 | break; |
| 348 | if (!*str) |
| 349 | return NULL; |
| 350 | |
| 351 | len = str - name; |
| 352 | tty_line = simple_strtoul(str, &str, 10); |
| 353 | |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 354 | mutex_lock(&tty_mutex); |
| 355 | /* Search through the tty devices to look for a match */ |
| 356 | list_for_each_entry(p, &tty_drivers, tty_drivers) { |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 357 | if (strncmp(name, p->name, len) != 0) |
| 358 | continue; |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 359 | stp = str; |
| 360 | if (*stp == ',') |
| 361 | stp++; |
| 362 | if (*stp == '\0') |
| 363 | stp = NULL; |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 364 | |
Nathael Pajani | 6eb68d6 | 2010-09-02 16:06:16 +0200 | [diff] [blame] | 365 | if (tty_line >= 0 && tty_line < p->num && p->ops && |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 366 | p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 367 | res = tty_driver_kref_get(p); |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 368 | *line = tty_line; |
| 369 | break; |
| 370 | } |
| 371 | } |
| 372 | mutex_unlock(&tty_mutex); |
| 373 | |
| 374 | return res; |
| 375 | } |
| 376 | EXPORT_SYMBOL_GPL(tty_find_polling_driver); |
| 377 | #endif |
| 378 | |
Peter Hurley | e802ca0 | 2016-01-09 21:35:21 -0800 | [diff] [blame] | 379 | static int is_ignored(int sig) |
| 380 | { |
| 381 | return (sigismember(¤t->blocked, sig) || |
| 382 | current->sighand->action[sig-1].sa.sa_handler == SIG_IGN); |
| 383 | } |
| 384 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 385 | /** |
| 386 | * tty_check_change - check for POSIX terminal changes |
| 387 | * @tty: tty to check |
| 388 | * |
| 389 | * If we try to write to, or set the state of, a terminal and we're |
| 390 | * not in the foreground, send a SIGTTOU. If the signal is blocked or |
| 391 | * ignored, go ahead and perform the operation. (POSIX 7.2) |
| 392 | * |
Alan Cox | 978e595 | 2008-04-30 00:53:59 -0700 | [diff] [blame] | 393 | * Locking: ctrl_lock |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 395 | |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 396 | int __tty_check_change(struct tty_struct *tty, int sig) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 398 | unsigned long flags; |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 399 | struct pid *pgrp, *tty_pgrp; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 400 | int ret = 0; |
| 401 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | if (current->signal->tty != tty) |
| 403 | return 0; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 404 | |
Patrick Donnelly | 6719693 | 2015-07-12 18:51:52 -0400 | [diff] [blame] | 405 | rcu_read_lock(); |
| 406 | pgrp = task_pgrp(current); |
| 407 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 408 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 409 | tty_pgrp = tty->pgrp; |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 410 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Patrick Donnelly | 6719693 | 2015-07-12 18:51:52 -0400 | [diff] [blame] | 411 | |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 412 | if (tty_pgrp && pgrp != tty->pgrp) { |
| 413 | if (is_ignored(sig)) { |
| 414 | if (sig == SIGTTIN) |
| 415 | ret = -EIO; |
| 416 | } else if (is_current_pgrp_orphaned()) |
| 417 | ret = -EIO; |
| 418 | else { |
| 419 | kill_pgrp(pgrp, sig, 1); |
| 420 | set_thread_flag(TIF_SIGPENDING); |
| 421 | ret = -ERESTARTSYS; |
| 422 | } |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 423 | } |
Patrick Donnelly | 6719693 | 2015-07-12 18:51:52 -0400 | [diff] [blame] | 424 | rcu_read_unlock(); |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 425 | |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 426 | if (!tty_pgrp) |
| 427 | tty_warn(tty, "sig=%d, tty->pgrp == NULL!\n", sig); |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 428 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 429 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | } |
| 431 | |
Peter Hurley | 2812d9e | 2015-10-10 20:28:42 -0400 | [diff] [blame] | 432 | int tty_check_change(struct tty_struct *tty) |
| 433 | { |
| 434 | return __tty_check_change(tty, SIGTTOU); |
| 435 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | EXPORT_SYMBOL(tty_check_change); |
| 437 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 438 | static ssize_t hung_up_tty_read(struct file *file, char __user *buf, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | size_t count, loff_t *ppos) |
| 440 | { |
| 441 | return 0; |
| 442 | } |
| 443 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 444 | static ssize_t hung_up_tty_write(struct file *file, const char __user *buf, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 445 | size_t count, loff_t *ppos) |
| 446 | { |
| 447 | return -EIO; |
| 448 | } |
| 449 | |
| 450 | /* No kernel lock held - none needed ;) */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 451 | static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | { |
| 453 | return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; |
| 454 | } |
| 455 | |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 456 | static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, |
| 457 | unsigned long arg) |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 458 | { |
| 459 | return cmd == TIOCSPGRP ? -ENOTTY : -EIO; |
| 460 | } |
| 461 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 462 | static long hung_up_tty_compat_ioctl(struct file *file, |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 463 | unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | { |
| 465 | return cmd == TIOCSPGRP ? -ENOTTY : -EIO; |
| 466 | } |
| 467 | |
Peter Hurley | f557474 | 2016-01-09 21:45:10 -0800 | [diff] [blame] | 468 | static int hung_up_tty_fasync(int fd, struct file *file, int on) |
| 469 | { |
| 470 | return -ENOTTY; |
| 471 | } |
| 472 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 473 | static const struct file_operations tty_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | .llseek = no_llseek, |
| 475 | .read = tty_read, |
| 476 | .write = tty_write, |
| 477 | .poll = tty_poll, |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 478 | .unlocked_ioctl = tty_ioctl, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 479 | .compat_ioctl = tty_compat_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | .open = tty_open, |
| 481 | .release = tty_release, |
| 482 | .fasync = tty_fasync, |
| 483 | }; |
| 484 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 485 | static const struct file_operations console_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | .llseek = no_llseek, |
| 487 | .read = tty_read, |
| 488 | .write = redirected_tty_write, |
| 489 | .poll = tty_poll, |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 490 | .unlocked_ioctl = tty_ioctl, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 491 | .compat_ioctl = tty_compat_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 492 | .open = tty_open, |
| 493 | .release = tty_release, |
| 494 | .fasync = tty_fasync, |
| 495 | }; |
| 496 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 497 | static const struct file_operations hung_up_tty_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | .llseek = no_llseek, |
| 499 | .read = hung_up_tty_read, |
| 500 | .write = hung_up_tty_write, |
| 501 | .poll = hung_up_tty_poll, |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 502 | .unlocked_ioctl = hung_up_tty_ioctl, |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 503 | .compat_ioctl = hung_up_tty_compat_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | .release = tty_release, |
Peter Hurley | f557474 | 2016-01-09 21:45:10 -0800 | [diff] [blame] | 505 | .fasync = hung_up_tty_fasync, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | }; |
| 507 | |
| 508 | static DEFINE_SPINLOCK(redirect_lock); |
| 509 | static struct file *redirect; |
| 510 | |
Peter Hurley | 11d9bef | 2014-10-16 14:59:42 -0400 | [diff] [blame] | 511 | |
| 512 | void proc_clear_tty(struct task_struct *p) |
| 513 | { |
| 514 | unsigned long flags; |
| 515 | struct tty_struct *tty; |
| 516 | spin_lock_irqsave(&p->sighand->siglock, flags); |
| 517 | tty = p->signal->tty; |
| 518 | p->signal->tty = NULL; |
| 519 | spin_unlock_irqrestore(&p->sighand->siglock, flags); |
| 520 | tty_kref_put(tty); |
| 521 | } |
| 522 | |
Peter Hurley | 2c411c1 | 2014-10-16 14:59:47 -0400 | [diff] [blame] | 523 | /** |
| 524 | * proc_set_tty - set the controlling terminal |
| 525 | * |
| 526 | * Only callable by the session leader and only if it does not already have |
| 527 | * a controlling terminal. |
| 528 | * |
Peter Hurley | e218eb3 | 2014-10-16 14:59:49 -0400 | [diff] [blame] | 529 | * Caller must hold: tty_lock() |
| 530 | * a readlock on tasklist_lock |
Peter Hurley | 2c411c1 | 2014-10-16 14:59:47 -0400 | [diff] [blame] | 531 | * sighand lock |
| 532 | */ |
Peter Hurley | bce65f1 | 2014-10-16 14:59:43 -0400 | [diff] [blame] | 533 | static void __proc_set_tty(struct tty_struct *tty) |
Peter Hurley | 11d9bef | 2014-10-16 14:59:42 -0400 | [diff] [blame] | 534 | { |
Peter Hurley | ae28fa7 | 2014-10-16 14:59:46 -0400 | [diff] [blame] | 535 | unsigned long flags; |
| 536 | |
Peter Hurley | ae28fa7 | 2014-10-16 14:59:46 -0400 | [diff] [blame] | 537 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Peter Hurley | a361858 | 2014-10-16 14:59:50 -0400 | [diff] [blame] | 538 | /* |
| 539 | * The session and fg pgrp references will be non-NULL if |
| 540 | * tiocsctty() is stealing the controlling tty |
| 541 | */ |
Peter Hurley | ae28fa7 | 2014-10-16 14:59:46 -0400 | [diff] [blame] | 542 | put_pid(tty->session); |
| 543 | put_pid(tty->pgrp); |
| 544 | tty->pgrp = get_pid(task_pgrp(current)); |
| 545 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 546 | tty->session = get_pid(task_session(current)); |
| 547 | if (current->signal->tty) { |
Peter Hurley | e2dfa3d | 2015-07-12 22:49:08 -0400 | [diff] [blame] | 548 | tty_debug(tty, "current tty %s not NULL!!\n", |
| 549 | current->signal->tty->name); |
Peter Hurley | ae28fa7 | 2014-10-16 14:59:46 -0400 | [diff] [blame] | 550 | tty_kref_put(current->signal->tty); |
Peter Hurley | 11d9bef | 2014-10-16 14:59:42 -0400 | [diff] [blame] | 551 | } |
Peter Hurley | bce65f1 | 2014-10-16 14:59:43 -0400 | [diff] [blame] | 552 | put_pid(current->signal->tty_old_pgrp); |
| 553 | current->signal->tty = tty_kref_get(tty); |
| 554 | current->signal->tty_old_pgrp = NULL; |
Peter Hurley | 11d9bef | 2014-10-16 14:59:42 -0400 | [diff] [blame] | 555 | } |
| 556 | |
Peter Hurley | bce65f1 | 2014-10-16 14:59:43 -0400 | [diff] [blame] | 557 | static void proc_set_tty(struct tty_struct *tty) |
Peter Hurley | 11d9bef | 2014-10-16 14:59:42 -0400 | [diff] [blame] | 558 | { |
Peter Hurley | bce65f1 | 2014-10-16 14:59:43 -0400 | [diff] [blame] | 559 | spin_lock_irq(¤t->sighand->siglock); |
| 560 | __proc_set_tty(tty); |
| 561 | spin_unlock_irq(¤t->sighand->siglock); |
Peter Hurley | 11d9bef | 2014-10-16 14:59:42 -0400 | [diff] [blame] | 562 | } |
| 563 | |
| 564 | struct tty_struct *get_current_tty(void) |
| 565 | { |
| 566 | struct tty_struct *tty; |
| 567 | unsigned long flags; |
| 568 | |
| 569 | spin_lock_irqsave(¤t->sighand->siglock, flags); |
| 570 | tty = tty_kref_get(current->signal->tty); |
| 571 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); |
| 572 | return tty; |
| 573 | } |
| 574 | EXPORT_SYMBOL_GPL(get_current_tty); |
| 575 | |
| 576 | static void session_clear_tty(struct pid *session) |
| 577 | { |
| 578 | struct task_struct *p; |
| 579 | do_each_pid_task(session, PIDTYPE_SID, p) { |
| 580 | proc_clear_tty(p); |
| 581 | } while_each_pid_task(session, PIDTYPE_SID, p); |
| 582 | } |
| 583 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | /** |
| 585 | * tty_wakeup - request more data |
| 586 | * @tty: terminal |
| 587 | * |
| 588 | * Internal and external helper for wakeups of tty. This function |
| 589 | * informs the line discipline if present that the driver is ready |
| 590 | * to receive more output data. |
| 591 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 592 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | void tty_wakeup(struct tty_struct *tty) |
| 594 | { |
| 595 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 596 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { |
| 598 | ld = tty_ldisc_ref(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 599 | if (ld) { |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 600 | if (ld->ops->write_wakeup) |
| 601 | ld->ops->write_wakeup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | tty_ldisc_deref(ld); |
| 603 | } |
| 604 | } |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 605 | wake_up_interruptible_poll(&tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 606 | } |
| 607 | |
| 608 | EXPORT_SYMBOL_GPL(tty_wakeup); |
| 609 | |
| 610 | /** |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 611 | * tty_signal_session_leader - sends SIGHUP to session leader |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 612 | * @tty controlling tty |
| 613 | * @exit_session if non-zero, signal all foreground group processes |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 614 | * |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 615 | * Send SIGHUP and SIGCONT to the session leader and its process group. |
| 616 | * Optionally, signal all processes in the foreground process group. |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 617 | * |
| 618 | * Returns the number of processes in the session with this tty |
| 619 | * as their controlling terminal. This value is used to drop |
| 620 | * tty references for those processes. |
| 621 | */ |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 622 | static int tty_signal_session_leader(struct tty_struct *tty, int exit_session) |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 623 | { |
| 624 | struct task_struct *p; |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 625 | int refs = 0; |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 626 | struct pid *tty_pgrp = NULL; |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 627 | |
| 628 | read_lock(&tasklist_lock); |
| 629 | if (tty->session) { |
| 630 | do_each_pid_task(tty->session, PIDTYPE_SID, p) { |
| 631 | spin_lock_irq(&p->sighand->siglock); |
| 632 | if (p->signal->tty == tty) { |
| 633 | p->signal->tty = NULL; |
| 634 | /* We defer the dereferences outside fo |
| 635 | the tasklist lock */ |
| 636 | refs++; |
| 637 | } |
| 638 | if (!p->signal->leader) { |
| 639 | spin_unlock_irq(&p->sighand->siglock); |
| 640 | continue; |
| 641 | } |
| 642 | __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); |
| 643 | __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); |
| 644 | put_pid(p->signal->tty_old_pgrp); /* A noop */ |
Peter Hurley | bc30c3b | 2013-03-06 07:20:55 -0500 | [diff] [blame] | 645 | spin_lock(&tty->ctrl_lock); |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 646 | tty_pgrp = get_pid(tty->pgrp); |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 647 | if (tty->pgrp) |
| 648 | p->signal->tty_old_pgrp = get_pid(tty->pgrp); |
Peter Hurley | bc30c3b | 2013-03-06 07:20:55 -0500 | [diff] [blame] | 649 | spin_unlock(&tty->ctrl_lock); |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 650 | spin_unlock_irq(&p->sighand->siglock); |
| 651 | } while_each_pid_task(tty->session, PIDTYPE_SID, p); |
| 652 | } |
| 653 | read_unlock(&tasklist_lock); |
| 654 | |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 655 | if (tty_pgrp) { |
| 656 | if (exit_session) |
| 657 | kill_pgrp(tty_pgrp, SIGHUP, exit_session); |
| 658 | put_pid(tty_pgrp); |
| 659 | } |
| 660 | |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 661 | return refs; |
| 662 | } |
| 663 | |
| 664 | /** |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 665 | * __tty_hangup - actual handler for hangup events |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 666 | * @work: tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 667 | * |
Kevin Cernekee | ef4f527 | 2012-12-26 20:43:41 -0800 | [diff] [blame] | 668 | * This can be called by a "kworker" kernel thread. That is process |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 669 | * synchronous but doesn't hold any locks, so we need to make sure we |
| 670 | * have the appropriate locks for what we're doing. |
| 671 | * |
| 672 | * The hangup event clears any pending redirections onto the hung up |
| 673 | * device. It ensures future writes will error and it does the needed |
| 674 | * line discipline hangup and signal delivery. The tty object itself |
| 675 | * remains intact. |
| 676 | * |
| 677 | * Locking: |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 678 | * BTM |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 679 | * redirect lock for undoing redirection |
| 680 | * file list lock for manipulating list of ttys |
Peter Hurley | 137084b | 2013-06-15 07:04:46 -0400 | [diff] [blame] | 681 | * tty_ldiscs_lock from called functions |
Peter Hurley | 6a1c068 | 2013-06-15 09:14:23 -0400 | [diff] [blame] | 682 | * termios_rwsem resetting termios data |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 683 | * tasklist_lock to walk task list for hangup event |
| 684 | * ->siglock to protect ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | */ |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 686 | static void __tty_hangup(struct tty_struct *tty, int exit_session) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 687 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 688 | struct file *cons_filp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | struct file *filp, *f = NULL; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 690 | struct tty_file_private *priv; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | int closecount = 0, n; |
Peter Hurley | ea648a4 | 2013-03-06 07:20:53 -0500 | [diff] [blame] | 692 | int refs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 693 | |
| 694 | if (!tty) |
| 695 | return; |
| 696 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | |
| 698 | spin_lock(&redirect_lock); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 699 | if (redirect && file_tty(redirect) == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | f = redirect; |
| 701 | redirect = NULL; |
| 702 | } |
| 703 | spin_unlock(&redirect_lock); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 704 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 705 | tty_lock(tty); |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 706 | |
Peter Hurley | cb50e52 | 2013-07-31 14:05:45 -0400 | [diff] [blame] | 707 | if (test_bit(TTY_HUPPED, &tty->flags)) { |
| 708 | tty_unlock(tty); |
| 709 | return; |
| 710 | } |
| 711 | |
Tejun Heo | a7e1906 | 2018-02-13 07:38:08 -0800 | [diff] [blame] | 712 | /* |
| 713 | * Some console devices aren't actually hung up for technical and |
| 714 | * historical reasons, which can lead to indefinite interruptible |
| 715 | * sleep in n_tty_read(). The following explicitly tells |
| 716 | * n_tty_read() to abort readers. |
| 717 | */ |
| 718 | set_bit(TTY_HUPPING, &tty->flags); |
| 719 | |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 720 | /* inuse_filps is protected by the single tty lock, |
| 721 | this really needs to change if we want to flush the |
| 722 | workqueue with the lock held */ |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 723 | check_tty_count(tty, "tty_hangup"); |
Alan Cox | 36ba782 | 2009-11-30 13:18:51 +0000 | [diff] [blame] | 724 | |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 725 | spin_lock(&tty->files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | /* This breaks for file handles being sent over AF_UNIX sockets ? */ |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 727 | list_for_each_entry(priv, &tty->tty_files, list) { |
| 728 | filp = priv->file; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | if (filp->f_op->write == redirected_tty_write) |
| 730 | cons_filp = filp; |
| 731 | if (filp->f_op->write != tty_write) |
| 732 | continue; |
| 733 | closecount++; |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 734 | __tty_fasync(-1, filp, 0); /* can't block */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | filp->f_op = &hung_up_tty_fops; |
| 736 | } |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 737 | spin_unlock(&tty->files_lock); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 738 | |
Peter Hurley | 25fdf24 | 2013-03-06 07:20:57 -0500 | [diff] [blame] | 739 | refs = tty_signal_session_leader(tty, exit_session); |
| 740 | /* Account for the p->signal references we killed */ |
| 741 | while (refs--) |
| 742 | tty_kref_put(tty); |
| 743 | |
Peter Hurley | 892d1fa | 2016-01-10 22:41:06 -0800 | [diff] [blame] | 744 | tty_ldisc_hangup(tty, cons_filp != NULL); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 745 | |
Peter Hurley | 20cc225 | 2013-03-06 07:20:54 -0500 | [diff] [blame] | 746 | spin_lock_irq(&tty->ctrl_lock); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 747 | clear_bit(TTY_THROTTLED, &tty->flags); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 748 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
Eric W. Biederman | d9c1e9a | 2007-03-18 12:45:44 -0600 | [diff] [blame] | 749 | put_pid(tty->session); |
| 750 | put_pid(tty->pgrp); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 751 | tty->session = NULL; |
| 752 | tty->pgrp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | tty->ctrl_status = 0; |
Peter Hurley | 20cc225 | 2013-03-06 07:20:54 -0500 | [diff] [blame] | 754 | spin_unlock_irq(&tty->ctrl_lock); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 755 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 757 | * If one of the devices matches a console pointer, we |
| 758 | * cannot just call hangup() because that will cause |
| 759 | * tty->count and state->count to go out of sync. |
| 760 | * So we just call close() the right number of times. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | */ |
| 762 | if (cons_filp) { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 763 | if (tty->ops->close) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | for (n = 0; n < closecount; n++) |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 765 | tty->ops->close(tty, cons_filp); |
| 766 | } else if (tty->ops->hangup) |
Peter Hurley | 7c6d340 | 2014-06-16 09:17:08 -0400 | [diff] [blame] | 767 | tty->ops->hangup(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 768 | /* |
Peter Hurley | 892d1fa | 2016-01-10 22:41:06 -0800 | [diff] [blame] | 769 | * We don't want to have driver/ldisc interactions beyond the ones |
| 770 | * we did here. The driver layer expects no calls after ->hangup() |
| 771 | * from the ldisc side, which is now guaranteed. |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 772 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | set_bit(TTY_HUPPED, &tty->flags); |
Tejun Heo | a7e1906 | 2018-02-13 07:38:08 -0800 | [diff] [blame] | 774 | clear_bit(TTY_HUPPING, &tty->flags); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 775 | tty_unlock(tty); |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 776 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | if (f) |
| 778 | fput(f); |
| 779 | } |
| 780 | |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 781 | static void do_tty_hangup(struct work_struct *work) |
| 782 | { |
| 783 | struct tty_struct *tty = |
| 784 | container_of(work, struct tty_struct, hangup_work); |
| 785 | |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 786 | __tty_hangup(tty, 0); |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 787 | } |
| 788 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 789 | /** |
| 790 | * tty_hangup - trigger a hangup event |
| 791 | * @tty: tty to hangup |
| 792 | * |
| 793 | * A carrier loss (virtual or otherwise) has occurred on this like |
| 794 | * schedule a hangup sequence to run after this event. |
| 795 | */ |
| 796 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 797 | void tty_hangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | { |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 799 | tty_debug_hangup(tty, "hangup\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | schedule_work(&tty->hangup_work); |
| 801 | } |
| 802 | |
| 803 | EXPORT_SYMBOL(tty_hangup); |
| 804 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 805 | /** |
| 806 | * tty_vhangup - process vhangup |
| 807 | * @tty: tty to hangup |
| 808 | * |
| 809 | * The user has asked via system call for the terminal to be hung up. |
| 810 | * We do this synchronously so that when the syscall returns the process |
Robert P. J. Day | 3a4fa0a | 2007-10-19 23:10:43 +0200 | [diff] [blame] | 811 | * is complete. That guarantee is necessary for security reasons. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 812 | */ |
| 813 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 814 | void tty_vhangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | { |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 816 | tty_debug_hangup(tty, "vhangup\n"); |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 817 | __tty_hangup(tty, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 819 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | EXPORT_SYMBOL(tty_vhangup); |
| 821 | |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 822 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 823 | /** |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 824 | * tty_vhangup_self - process vhangup for own ctty |
| 825 | * |
| 826 | * Perform a vhangup on the current controlling tty |
| 827 | */ |
| 828 | |
| 829 | void tty_vhangup_self(void) |
| 830 | { |
| 831 | struct tty_struct *tty; |
| 832 | |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 833 | tty = get_current_tty(); |
| 834 | if (tty) { |
| 835 | tty_vhangup(tty); |
| 836 | tty_kref_put(tty); |
| 837 | } |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 838 | } |
| 839 | |
| 840 | /** |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 841 | * tty_vhangup_session - hangup session leader exit |
| 842 | * @tty: tty to hangup |
| 843 | * |
| 844 | * The session leader is exiting and hanging up its controlling terminal. |
| 845 | * Every process in the foreground process group is signalled SIGHUP. |
| 846 | * |
| 847 | * We do this synchronously so that when the syscall returns the process |
| 848 | * is complete. That guarantee is necessary for security reasons. |
| 849 | */ |
| 850 | |
Changlong Xie | 44a459f | 2013-03-20 08:42:04 +0800 | [diff] [blame] | 851 | static void tty_vhangup_session(struct tty_struct *tty) |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 852 | { |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 853 | tty_debug_hangup(tty, "session hangup\n"); |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 854 | __tty_hangup(tty, 1); |
| 855 | } |
| 856 | |
| 857 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 858 | * tty_hung_up_p - was tty hung up |
| 859 | * @filp: file pointer of tty |
| 860 | * |
| 861 | * Return true if the tty has been subject to a vhangup or a carrier |
| 862 | * loss |
| 863 | */ |
| 864 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 865 | int tty_hung_up_p(struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 866 | { |
| 867 | return (filp->f_op == &hung_up_tty_fops); |
| 868 | } |
| 869 | |
| 870 | EXPORT_SYMBOL(tty_hung_up_p); |
| 871 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 872 | /** |
| 873 | * disassociate_ctty - disconnect controlling tty |
| 874 | * @on_exit: true if exiting so need to "hang up" the session |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 875 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 876 | * This function is typically called only by the session leader, when |
| 877 | * it wants to disassociate itself from its controlling tty. |
| 878 | * |
| 879 | * It performs the following functions: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | * (1) Sends a SIGHUP and SIGCONT to the foreground process group |
| 881 | * (2) Clears the tty from being controlling the session |
| 882 | * (3) Clears the controlling tty for all processes in the |
| 883 | * session group. |
| 884 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 885 | * The argument on_exit is set to 1 if called when a process is |
| 886 | * exiting; it is 0 if called by the ioctl TIOCNOTTY. |
| 887 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 888 | * Locking: |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 889 | * BTM is taken for hysterical raisins, and held when |
| 890 | * called from no_tty(). |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 891 | * tty_mutex is taken to protect tty |
| 892 | * ->siglock is taken to protect ->signal/->sighand |
| 893 | * tasklist_lock is taken to walk process list for sessions |
| 894 | * ->siglock is taken to protect ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 896 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | void disassociate_ctty(int on_exit) |
| 898 | { |
| 899 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 900 | |
Alan Cox | 5ec93d1 | 2009-11-30 13:18:45 +0000 | [diff] [blame] | 901 | if (!current->signal->leader) |
| 902 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 903 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 904 | tty = get_current_tty(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 905 | if (tty) { |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 906 | if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) { |
| 907 | tty_vhangup_session(tty); |
| 908 | } else { |
| 909 | struct pid *tty_pgrp = tty_get_pgrp(tty); |
| 910 | if (tty_pgrp) { |
| 911 | kill_pgrp(tty_pgrp, SIGHUP, on_exit); |
Oleg Nesterov | 03e1261 | 2013-09-15 17:50:26 +0200 | [diff] [blame] | 912 | if (!on_exit) |
| 913 | kill_pgrp(tty_pgrp, SIGCONT, on_exit); |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 914 | put_pid(tty_pgrp); |
| 915 | } |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 916 | } |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 917 | tty_kref_put(tty); |
Peter Hurley | f91e259 | 2013-03-06 07:20:56 -0500 | [diff] [blame] | 918 | |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 919 | } else if (on_exit) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 920 | struct pid *old_pgrp; |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 921 | spin_lock_irq(¤t->sighand->siglock); |
| 922 | old_pgrp = current->signal->tty_old_pgrp; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 923 | current->signal->tty_old_pgrp = NULL; |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 924 | spin_unlock_irq(¤t->sighand->siglock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 925 | if (old_pgrp) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 926 | kill_pgrp(old_pgrp, SIGHUP, on_exit); |
| 927 | kill_pgrp(old_pgrp, SIGCONT, on_exit); |
| 928 | put_pid(old_pgrp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 929 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | return; |
| 931 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 932 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 933 | spin_lock_irq(¤t->sighand->siglock); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 934 | put_pid(current->signal->tty_old_pgrp); |
Randy Dunlap | 23cac8d | 2007-02-20 13:58:05 -0800 | [diff] [blame] | 935 | current->signal->tty_old_pgrp = NULL; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 936 | |
Chen Tingjie | c70dbb1 | 2014-04-15 11:52:51 +0800 | [diff] [blame] | 937 | tty = tty_kref_get(current->signal->tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 938 | if (tty) { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 939 | unsigned long flags; |
| 940 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 941 | put_pid(tty->session); |
| 942 | put_pid(tty->pgrp); |
| 943 | tty->session = NULL; |
| 944 | tty->pgrp = NULL; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 945 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 946 | tty_kref_put(tty); |
Peter Hurley | accff79 | 2015-07-12 22:49:09 -0400 | [diff] [blame] | 947 | } else |
| 948 | tty_debug_hangup(tty, "no current tty\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 949 | |
Chen Tingjie | c70dbb1 | 2014-04-15 11:52:51 +0800 | [diff] [blame] | 950 | spin_unlock_irq(¤t->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 951 | /* Now clear signal->tty under the lock */ |
| 952 | read_lock(&tasklist_lock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 953 | session_clear_tty(task_session(current)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | read_unlock(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 955 | } |
| 956 | |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 957 | /** |
| 958 | * |
| 959 | * no_tty - Ensure the current process does not have a controlling tty |
| 960 | */ |
| 961 | void no_tty(void) |
| 962 | { |
Alan Cox | 3af502b | 2012-05-03 22:21:53 +0100 | [diff] [blame] | 963 | /* FIXME: Review locking here. The tty_lock never covered any race |
| 964 | between a new association and proc_clear_tty but possible we need |
| 965 | to protect against this anyway */ |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 966 | struct task_struct *tsk = current; |
Alan Cox | 5ec93d1 | 2009-11-30 13:18:45 +0000 | [diff] [blame] | 967 | disassociate_ctty(0); |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 968 | proc_clear_tty(tsk); |
| 969 | } |
| 970 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 971 | |
| 972 | /** |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 973 | * stop_tty - propagate flow control |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 974 | * @tty: tty to stop |
| 975 | * |
Peter Hurley | 01adc80 | 2014-09-10 15:06:32 -0400 | [diff] [blame] | 976 | * Perform flow control to the driver. May be called |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 977 | * on an already stopped device and will not re-call the driver |
| 978 | * method. |
| 979 | * |
| 980 | * This functionality is used by both the line disciplines for |
| 981 | * halting incoming flow and by the driver. It may therefore be |
| 982 | * called from any context, may be under the tty atomic_write_lock |
| 983 | * but not always. |
| 984 | * |
| 985 | * Locking: |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 986 | * flow_lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 987 | */ |
| 988 | |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 989 | void __stop_tty(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 990 | { |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 991 | if (tty->stopped) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 992 | return; |
| 993 | tty->stopped = 1; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 994 | if (tty->ops->stop) |
Peter Hurley | c961bfb | 2014-11-05 12:26:25 -0500 | [diff] [blame] | 995 | tty->ops->stop(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 996 | } |
| 997 | |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 998 | void stop_tty(struct tty_struct *tty) |
| 999 | { |
| 1000 | unsigned long flags; |
| 1001 | |
| 1002 | spin_lock_irqsave(&tty->flow_lock, flags); |
| 1003 | __stop_tty(tty); |
| 1004 | spin_unlock_irqrestore(&tty->flow_lock, flags); |
| 1005 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1006 | EXPORT_SYMBOL(stop_tty); |
| 1007 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1008 | /** |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 1009 | * start_tty - propagate flow control |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1010 | * @tty: tty to start |
| 1011 | * |
Peter Hurley | 01adc80 | 2014-09-10 15:06:32 -0400 | [diff] [blame] | 1012 | * Start a tty that has been stopped if at all possible. If this |
| 1013 | * tty was previous stopped and is now being started, the driver |
| 1014 | * start method is invoked and the line discipline woken. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1015 | * |
| 1016 | * Locking: |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 1017 | * flow_lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1018 | */ |
| 1019 | |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 1020 | void __start_tty(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | { |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 1022 | if (!tty->stopped || tty->flow_stopped) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1023 | return; |
| 1024 | tty->stopped = 0; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1025 | if (tty->ops->start) |
Peter Hurley | c961bfb | 2014-11-05 12:26:25 -0500 | [diff] [blame] | 1026 | tty->ops->start(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | tty_wakeup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1028 | } |
| 1029 | |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 1030 | void start_tty(struct tty_struct *tty) |
| 1031 | { |
| 1032 | unsigned long flags; |
| 1033 | |
| 1034 | spin_lock_irqsave(&tty->flow_lock, flags); |
| 1035 | __start_tty(tty); |
| 1036 | spin_unlock_irqrestore(&tty->flow_lock, flags); |
| 1037 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | EXPORT_SYMBOL(start_tty); |
| 1039 | |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1040 | static void tty_update_time(struct timespec *time) |
| 1041 | { |
Jiri Slaby | f0bf0bd | 2015-02-27 18:40:31 +0100 | [diff] [blame] | 1042 | unsigned long sec = get_seconds(); |
Greg Kroah-Hartman | fbf4763 | 2015-03-26 23:10:27 +0100 | [diff] [blame] | 1043 | |
| 1044 | /* |
| 1045 | * We only care if the two values differ in anything other than the |
| 1046 | * lower three bits (i.e every 8 seconds). If so, then we can update |
| 1047 | * the time of the tty device, otherwise it could be construded as a |
| 1048 | * security leak to let userspace know the exact timing of the tty. |
| 1049 | */ |
| 1050 | if ((sec ^ time->tv_sec) & ~7) |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1051 | time->tv_sec = sec; |
| 1052 | } |
| 1053 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1054 | /** |
| 1055 | * tty_read - read method for tty device files |
| 1056 | * @file: pointer to tty file |
| 1057 | * @buf: user buffer |
| 1058 | * @count: size of user buffer |
| 1059 | * @ppos: unused |
| 1060 | * |
| 1061 | * Perform the read system call function on this terminal device. Checks |
| 1062 | * for hung up devices before calling the line discipline method. |
| 1063 | * |
| 1064 | * Locking: |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 1065 | * Locks the line discipline internally while needed. Multiple |
| 1066 | * read calls may be outstanding in parallel. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1067 | */ |
| 1068 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1069 | static ssize_t tty_read(struct file *file, char __user *buf, size_t count, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | loff_t *ppos) |
| 1071 | { |
| 1072 | int i; |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1073 | struct inode *inode = file_inode(file); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1074 | struct tty_struct *tty = file_tty(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1075 | struct tty_ldisc *ld; |
| 1076 | |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1077 | if (tty_paranoia_check(tty, inode, "tty_read")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1078 | return -EIO; |
Peter Hurley | 18900ca | 2016-04-09 17:06:48 -0700 | [diff] [blame] | 1079 | if (!tty || tty_io_error(tty)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1080 | return -EIO; |
| 1081 | |
| 1082 | /* We want to wait for the line discipline to sort out in this |
| 1083 | situation */ |
| 1084 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 1085 | if (!ld) |
| 1086 | return hung_up_tty_read(file, buf, count, ppos); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1087 | if (ld->ops->read) |
Peter Hurley | c961bfb | 2014-11-05 12:26:25 -0500 | [diff] [blame] | 1088 | i = ld->ops->read(tty, file, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1089 | else |
| 1090 | i = -EIO; |
| 1091 | tty_ldisc_deref(ld); |
Jiri Slaby | b0de59b | 2013-02-15 15:25:05 +0100 | [diff] [blame] | 1092 | |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1093 | if (i > 0) |
| 1094 | tty_update_time(&inode->i_atime); |
| 1095 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1096 | return i; |
| 1097 | } |
| 1098 | |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1099 | static void tty_write_unlock(struct tty_struct *tty) |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1100 | { |
| 1101 | mutex_unlock(&tty->atomic_write_lock); |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1102 | wake_up_interruptible_poll(&tty->write_wait, POLLOUT); |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1103 | } |
| 1104 | |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1105 | static int tty_write_lock(struct tty_struct *tty, int ndelay) |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1106 | { |
| 1107 | if (!mutex_trylock(&tty->atomic_write_lock)) { |
| 1108 | if (ndelay) |
| 1109 | return -EAGAIN; |
| 1110 | if (mutex_lock_interruptible(&tty->atomic_write_lock)) |
| 1111 | return -ERESTARTSYS; |
| 1112 | } |
| 1113 | return 0; |
| 1114 | } |
| 1115 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1116 | /* |
| 1117 | * Split writes up in sane blocksizes to avoid |
| 1118 | * denial-of-service type attacks |
| 1119 | */ |
| 1120 | static inline ssize_t do_tty_write( |
| 1121 | ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), |
| 1122 | struct tty_struct *tty, |
| 1123 | struct file *file, |
| 1124 | const char __user *buf, |
| 1125 | size_t count) |
| 1126 | { |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1127 | ssize_t ret, written = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | unsigned int chunk; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1129 | |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1130 | ret = tty_write_lock(tty, file->f_flags & O_NDELAY); |
| 1131 | if (ret < 0) |
| 1132 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | |
| 1134 | /* |
| 1135 | * We chunk up writes into a temporary buffer. This |
| 1136 | * simplifies low-level drivers immensely, since they |
| 1137 | * don't have locking issues and user mode accesses. |
| 1138 | * |
| 1139 | * But if TTY_NO_WRITE_SPLIT is set, we should use a |
| 1140 | * big chunk-size.. |
| 1141 | * |
| 1142 | * The default chunk-size is 2kB, because the NTTY |
| 1143 | * layer has problems with bigger chunks. It will |
| 1144 | * claim to be able to handle more characters than |
| 1145 | * it actually does. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1146 | * |
| 1147 | * FIXME: This can probably go away now except that 64K chunks |
| 1148 | * are too likely to fail unless switched to vmalloc... |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1149 | */ |
| 1150 | chunk = 2048; |
| 1151 | if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) |
| 1152 | chunk = 65536; |
| 1153 | if (count < chunk) |
| 1154 | chunk = count; |
| 1155 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1156 | /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1157 | if (tty->write_cnt < chunk) { |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 1158 | unsigned char *buf_chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1159 | |
| 1160 | if (chunk < 1024) |
| 1161 | chunk = 1024; |
| 1162 | |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 1163 | buf_chunk = kmalloc(chunk, GFP_KERNEL); |
| 1164 | if (!buf_chunk) { |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1165 | ret = -ENOMEM; |
| 1166 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1167 | } |
| 1168 | kfree(tty->write_buf); |
| 1169 | tty->write_cnt = chunk; |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 1170 | tty->write_buf = buf_chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1171 | } |
| 1172 | |
| 1173 | /* Do the write .. */ |
| 1174 | for (;;) { |
| 1175 | size_t size = count; |
| 1176 | if (size > chunk) |
| 1177 | size = chunk; |
| 1178 | ret = -EFAULT; |
| 1179 | if (copy_from_user(tty->write_buf, buf, size)) |
| 1180 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | ret = write(tty, file, tty->write_buf, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1182 | if (ret <= 0) |
| 1183 | break; |
| 1184 | written += ret; |
| 1185 | buf += ret; |
| 1186 | count -= ret; |
| 1187 | if (!count) |
| 1188 | break; |
| 1189 | ret = -ERESTARTSYS; |
| 1190 | if (signal_pending(current)) |
| 1191 | break; |
| 1192 | cond_resched(); |
| 1193 | } |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1194 | if (written) { |
| 1195 | tty_update_time(&file_inode(file)->i_mtime); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1196 | ret = written; |
Jiri Slaby | 37b7f3c | 2013-04-26 13:48:53 +0200 | [diff] [blame] | 1197 | } |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1198 | out: |
| 1199 | tty_write_unlock(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1200 | return ret; |
| 1201 | } |
| 1202 | |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1203 | /** |
| 1204 | * tty_write_message - write a message to a certain tty, not just the console. |
| 1205 | * @tty: the destination tty_struct |
| 1206 | * @msg: the message to write |
| 1207 | * |
| 1208 | * This is used for messages that need to be redirected to a specific tty. |
| 1209 | * We don't put it into the syslog queue right now maybe in the future if |
| 1210 | * really needed. |
| 1211 | * |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 1212 | * We must still hold the BTM and test the CLOSING flag for the moment. |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1213 | */ |
| 1214 | |
| 1215 | void tty_write_message(struct tty_struct *tty, char *msg) |
| 1216 | { |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1217 | if (tty) { |
| 1218 | mutex_lock(&tty->atomic_write_lock); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1219 | tty_lock(tty); |
Peter Hurley | 4b41b95 | 2015-10-10 20:28:44 -0400 | [diff] [blame] | 1220 | if (tty->ops->write && tty->count > 0) |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1221 | tty->ops->write(tty, msg, strlen(msg)); |
Peter Hurley | 4b41b95 | 2015-10-10 20:28:44 -0400 | [diff] [blame] | 1222 | tty_unlock(tty); |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1223 | tty_write_unlock(tty); |
| 1224 | } |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1225 | return; |
| 1226 | } |
| 1227 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1228 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1229 | /** |
| 1230 | * tty_write - write method for tty device file |
| 1231 | * @file: tty file pointer |
| 1232 | * @buf: user data to write |
| 1233 | * @count: bytes to write |
| 1234 | * @ppos: unused |
| 1235 | * |
| 1236 | * Write data to a tty device via the line discipline. |
| 1237 | * |
| 1238 | * Locking: |
| 1239 | * Locks the line discipline as required |
| 1240 | * Writes to the tty driver are serialized by the atomic_write_lock |
| 1241 | * and are then processed in chunks to the device. The line discipline |
Joe Peterson | a88a69c | 2009-01-02 13:40:53 +0000 | [diff] [blame] | 1242 | * write method will not be invoked in parallel for each device. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1243 | */ |
| 1244 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1245 | static ssize_t tty_write(struct file *file, const char __user *buf, |
| 1246 | size_t count, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1247 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1248 | struct tty_struct *tty = file_tty(file); |
| 1249 | struct tty_ldisc *ld; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1250 | ssize_t ret; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1251 | |
Al Viro | 6131ffa | 2013-02-27 16:59:05 -0500 | [diff] [blame] | 1252 | if (tty_paranoia_check(tty, file_inode(file), "tty_write")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1253 | return -EIO; |
Peter Hurley | 18900ca | 2016-04-09 17:06:48 -0700 | [diff] [blame] | 1254 | if (!tty || !tty->ops->write || tty_io_error(tty)) |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1255 | return -EIO; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1256 | /* Short term debug to catch buggy drivers */ |
| 1257 | if (tty->ops->write_room == NULL) |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 1258 | tty_err(tty, "missing write_room method\n"); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1259 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 1260 | if (!ld) |
| 1261 | return hung_up_tty_write(file, buf, count, ppos); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1262 | if (!ld->ops->write) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1263 | ret = -EIO; |
| 1264 | else |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1265 | ret = do_tty_write(ld->ops->write, tty, file, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1266 | tty_ldisc_deref(ld); |
| 1267 | return ret; |
| 1268 | } |
| 1269 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1270 | ssize_t redirected_tty_write(struct file *file, const char __user *buf, |
| 1271 | size_t count, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1272 | { |
| 1273 | struct file *p = NULL; |
| 1274 | |
| 1275 | spin_lock(&redirect_lock); |
Al Viro | cb0942b | 2012-08-27 14:48:26 -0400 | [diff] [blame] | 1276 | if (redirect) |
| 1277 | p = get_file(redirect); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1278 | spin_unlock(&redirect_lock); |
| 1279 | |
| 1280 | if (p) { |
| 1281 | ssize_t res; |
| 1282 | res = vfs_write(p, buf, count, &p->f_pos); |
| 1283 | fput(p); |
| 1284 | return res; |
| 1285 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1286 | return tty_write(file, buf, count, ppos); |
| 1287 | } |
| 1288 | |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1289 | /** |
| 1290 | * tty_send_xchar - send priority character |
| 1291 | * |
| 1292 | * Send a high priority character to the tty even if stopped |
| 1293 | * |
| 1294 | * Locking: none for xchar method, write ordering for write method. |
| 1295 | */ |
| 1296 | |
| 1297 | int tty_send_xchar(struct tty_struct *tty, char ch) |
| 1298 | { |
| 1299 | int was_stopped = tty->stopped; |
| 1300 | |
| 1301 | if (tty->ops->send_xchar) { |
Peter Hurley | ee0c1a6 | 2015-11-11 08:03:54 -0500 | [diff] [blame] | 1302 | down_read(&tty->termios_rwsem); |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1303 | tty->ops->send_xchar(tty, ch); |
Peter Hurley | ee0c1a6 | 2015-11-11 08:03:54 -0500 | [diff] [blame] | 1304 | up_read(&tty->termios_rwsem); |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1305 | return 0; |
| 1306 | } |
| 1307 | |
| 1308 | if (tty_write_lock(tty, 0) < 0) |
| 1309 | return -ERESTARTSYS; |
| 1310 | |
Peter Hurley | ee0c1a6 | 2015-11-11 08:03:54 -0500 | [diff] [blame] | 1311 | down_read(&tty->termios_rwsem); |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1312 | if (was_stopped) |
| 1313 | start_tty(tty); |
| 1314 | tty->ops->write(tty, &ch, 1); |
| 1315 | if (was_stopped) |
| 1316 | stop_tty(tty); |
Peter Hurley | ee0c1a6 | 2015-11-11 08:03:54 -0500 | [diff] [blame] | 1317 | up_read(&tty->termios_rwsem); |
Peter Hurley | 136d525 | 2014-09-10 15:06:34 -0400 | [diff] [blame] | 1318 | tty_write_unlock(tty); |
| 1319 | return 0; |
| 1320 | } |
| 1321 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1322 | static char ptychar[] = "pqrstuvwxyzabcde"; |
| 1323 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1324 | /** |
| 1325 | * pty_line_name - generate name for a pty |
| 1326 | * @driver: the tty driver in use |
| 1327 | * @index: the minor number |
| 1328 | * @p: output buffer of at least 6 bytes |
| 1329 | * |
| 1330 | * Generate a name from a driver reference and write it to the output |
| 1331 | * buffer. |
| 1332 | * |
| 1333 | * Locking: None |
| 1334 | */ |
| 1335 | static void pty_line_name(struct tty_driver *driver, int index, char *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1336 | { |
| 1337 | int i = index + driver->name_base; |
| 1338 | /* ->name is initialized to "ttyp", but "tty" is expected */ |
| 1339 | sprintf(p, "%s%c%x", |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1340 | driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, |
| 1341 | ptychar[i >> 4 & 0xf], i & 0xf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1342 | } |
| 1343 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1344 | /** |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1345 | * tty_line_name - generate name for a tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1346 | * @driver: the tty driver in use |
| 1347 | * @index: the minor number |
| 1348 | * @p: output buffer of at least 7 bytes |
| 1349 | * |
| 1350 | * Generate a name from a driver reference and write it to the output |
Greg Kroah-Hartman | 5c0a245 | 2014-02-22 14:31:04 -0800 | [diff] [blame] | 1351 | * buffer. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1352 | * |
| 1353 | * Locking: None |
| 1354 | */ |
Hannes Reinecke | 723abd8 | 2014-02-27 12:30:51 +0100 | [diff] [blame] | 1355 | static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1356 | { |
Jiri Slaby | 0019b40 | 2012-08-08 22:26:43 +0200 | [diff] [blame] | 1357 | if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE) |
Hannes Reinecke | 723abd8 | 2014-02-27 12:30:51 +0100 | [diff] [blame] | 1358 | return sprintf(p, "%s", driver->name); |
Jiri Slaby | 0019b40 | 2012-08-08 22:26:43 +0200 | [diff] [blame] | 1359 | else |
Hannes Reinecke | 723abd8 | 2014-02-27 12:30:51 +0100 | [diff] [blame] | 1360 | return sprintf(p, "%s%d", driver->name, |
| 1361 | index + driver->name_base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1362 | } |
| 1363 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1364 | /** |
| 1365 | * tty_driver_lookup_tty() - find an existing tty, if any |
| 1366 | * @driver: the driver for the tty |
| 1367 | * @idx: the minor number |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1368 | * |
Peter Hurley | aa3cb81 | 2014-11-05 12:12:51 -0500 | [diff] [blame] | 1369 | * Return the tty, if found. If not found, return NULL or ERR_PTR() if the |
| 1370 | * driver lookup() method returns an error. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1371 | * |
Peter Hurley | aa3cb81 | 2014-11-05 12:12:51 -0500 | [diff] [blame] | 1372 | * Locking: tty_mutex must be held. If the tty is found, bump the tty kref. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1373 | */ |
Jason Wessel | a47d545 | 2009-01-02 13:43:04 +0000 | [diff] [blame] | 1374 | static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, |
Linus Torvalds | 8ead9dd | 2016-04-25 20:04:08 -0700 | [diff] [blame] | 1375 | struct file *file, int idx) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1376 | { |
Peter Hurley | aa3cb81 | 2014-11-05 12:12:51 -0500 | [diff] [blame] | 1377 | struct tty_struct *tty; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1378 | |
Peter Hurley | aa3cb81 | 2014-11-05 12:12:51 -0500 | [diff] [blame] | 1379 | if (driver->ops->lookup) |
Linus Torvalds | 8ead9dd | 2016-04-25 20:04:08 -0700 | [diff] [blame] | 1380 | tty = driver->ops->lookup(driver, file, idx); |
Peter Hurley | aa3cb81 | 2014-11-05 12:12:51 -0500 | [diff] [blame] | 1381 | else |
| 1382 | tty = driver->ttys[idx]; |
| 1383 | |
| 1384 | if (!IS_ERR(tty)) |
| 1385 | tty_kref_get(tty); |
| 1386 | return tty; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1387 | } |
| 1388 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1389 | /** |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1390 | * tty_init_termios - helper for termios setup |
| 1391 | * @tty: the tty to set up |
| 1392 | * |
| 1393 | * Initialise the termios structures for this tty. Thus runs under |
| 1394 | * the tty_mutex currently so we can be relaxed about ordering. |
| 1395 | */ |
| 1396 | |
Peter Hurley | a3123fd | 2016-01-09 21:13:48 -0800 | [diff] [blame] | 1397 | void tty_init_termios(struct tty_struct *tty) |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1398 | { |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 1399 | struct ktermios *tp; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1400 | int idx = tty->index; |
| 1401 | |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1402 | if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) |
| 1403 | tty->termios = tty->driver->init_termios; |
| 1404 | else { |
| 1405 | /* Check for lazy saved data */ |
| 1406 | tp = tty->driver->termios[idx]; |
Peter Hurley | ece5340 | 2016-01-10 22:40:57 -0800 | [diff] [blame] | 1407 | if (tp != NULL) { |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1408 | tty->termios = *tp; |
Peter Hurley | ece5340 | 2016-01-10 22:40:57 -0800 | [diff] [blame] | 1409 | tty->termios.c_line = tty->driver->init_termios.c_line; |
| 1410 | } else |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1411 | tty->termios = tty->driver->init_termios; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1412 | } |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1413 | /* Compatibility until drivers always set this */ |
Alan Cox | adc8d74 | 2012-07-14 15:31:47 +0100 | [diff] [blame] | 1414 | tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios); |
| 1415 | tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1416 | } |
Alan Cox | fe1ae7f | 2009-09-19 13:13:33 -0700 | [diff] [blame] | 1417 | EXPORT_SYMBOL_GPL(tty_init_termios); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1418 | |
Jiri Slaby | 66d450e | 2012-01-30 21:14:28 +0100 | [diff] [blame] | 1419 | int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty) |
| 1420 | { |
Peter Hurley | a3123fd | 2016-01-09 21:13:48 -0800 | [diff] [blame] | 1421 | tty_init_termios(tty); |
Jiri Slaby | 66d450e | 2012-01-30 21:14:28 +0100 | [diff] [blame] | 1422 | tty_driver_kref_get(driver); |
| 1423 | tty->count++; |
| 1424 | driver->ttys[tty->index] = tty; |
| 1425 | return 0; |
| 1426 | } |
| 1427 | EXPORT_SYMBOL_GPL(tty_standard_install); |
| 1428 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1429 | /** |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1430 | * tty_driver_install_tty() - install a tty entry in the driver |
| 1431 | * @driver: the driver for the tty |
| 1432 | * @tty: the tty |
| 1433 | * |
| 1434 | * Install a tty object into the driver tables. The tty->index field |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1435 | * will be set by the time this is called. This method is responsible |
| 1436 | * for ensuring any need additional structures are allocated and |
| 1437 | * configured. |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1438 | * |
| 1439 | * Locking: tty_mutex for now |
| 1440 | */ |
| 1441 | static int tty_driver_install_tty(struct tty_driver *driver, |
| 1442 | struct tty_struct *tty) |
| 1443 | { |
Jiri Slaby | 66d450e | 2012-01-30 21:14:28 +0100 | [diff] [blame] | 1444 | return driver->ops->install ? driver->ops->install(driver, tty) : |
| 1445 | tty_standard_install(driver, tty); |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1446 | } |
| 1447 | |
| 1448 | /** |
| 1449 | * tty_driver_remove_tty() - remove a tty from the driver tables |
| 1450 | * @driver: the driver for the tty |
| 1451 | * @idx: the minor number |
| 1452 | * |
| 1453 | * Remvoe a tty object from the driver tables. The tty->index field |
| 1454 | * will be set by the time this is called. |
| 1455 | * |
| 1456 | * Locking: tty_mutex for now |
| 1457 | */ |
Peter Hurley | 05de87ed | 2016-01-09 21:13:49 -0800 | [diff] [blame] | 1458 | static void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty) |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1459 | { |
| 1460 | if (driver->ops->remove) |
| 1461 | driver->ops->remove(driver, tty); |
| 1462 | else |
| 1463 | driver->ttys[tty->index] = NULL; |
| 1464 | } |
| 1465 | |
| 1466 | /* |
| 1467 | * tty_reopen() - fast re-open of an open tty |
| 1468 | * @tty - the tty to open |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1469 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1470 | * Return 0 on success, -errno on error. |
Peter Hurley | 5d93e74 | 2014-11-05 12:12:47 -0500 | [diff] [blame] | 1471 | * Re-opens on master ptys are not allowed and return -EIO. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1472 | * |
Peter Hurley | 5d93e74 | 2014-11-05 12:12:47 -0500 | [diff] [blame] | 1473 | * Locking: Caller must hold tty_lock |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1474 | */ |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1475 | static int tty_reopen(struct tty_struct *tty) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1476 | { |
| 1477 | struct tty_driver *driver = tty->driver; |
| 1478 | |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1479 | if (driver->type == TTY_DRIVER_TYPE_PTY && |
Peter Hurley | 5d93e74 | 2014-11-05 12:12:47 -0500 | [diff] [blame] | 1480 | driver->subtype == PTY_TYPE_MASTER) |
| 1481 | return -EIO; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1482 | |
Peter Hurley | 7f22f6c | 2016-01-09 21:13:45 -0800 | [diff] [blame] | 1483 | if (!tty->count) |
| 1484 | return -EAGAIN; |
| 1485 | |
Peter Hurley | 86f2c00 | 2014-12-30 10:39:25 -0500 | [diff] [blame] | 1486 | if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN)) |
| 1487 | return -EBUSY; |
| 1488 | |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1489 | tty->count++; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1490 | |
Peter Hurley | 892d1fa | 2016-01-10 22:41:06 -0800 | [diff] [blame] | 1491 | if (!tty->ldisc) |
| 1492 | return tty_ldisc_reinit(tty, tty->termios.c_line); |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1493 | |
| 1494 | return 0; |
| 1495 | } |
| 1496 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1497 | /** |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1498 | * tty_init_dev - initialise a tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1499 | * @driver: tty driver we are opening a device on |
| 1500 | * @idx: device index |
Alan Cox | 15582d3 | 2008-10-13 10:41:03 +0100 | [diff] [blame] | 1501 | * @ret_tty: returned tty structure |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1502 | * |
| 1503 | * Prepare a tty device. This may not be a "new" clean device but |
| 1504 | * could also be an active device. The pty drivers require special |
| 1505 | * handling because of this. |
| 1506 | * |
| 1507 | * Locking: |
| 1508 | * The function is called under the tty_mutex, which |
| 1509 | * protects us from the tty struct or driver itself going away. |
| 1510 | * |
| 1511 | * On exit the tty device has the line discipline attached and |
| 1512 | * a reference count of 1. If a pair was created for pty/tty use |
| 1513 | * and the other was a pty master then it too has a reference count of 1. |
| 1514 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1515 | * WSH 06/09/97: Rewritten to remove races and properly clean up after a |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1516 | * failed open. The new code protects the open with a mutex, so it's |
| 1517 | * really quite straightforward. The mutex locking can probably be |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1518 | * relaxed for the (most common) case of reopening a tty. |
| 1519 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1520 | |
Konstantin Khlebnikov | 593a27c | 2012-01-05 13:04:21 +0400 | [diff] [blame] | 1521 | struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1522 | { |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1523 | struct tty_struct *tty; |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1524 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1525 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1526 | /* |
| 1527 | * First time open is complex, especially for PTY devices. |
| 1528 | * This code guarantees that either everything succeeds and the |
| 1529 | * TTY is ready for operation, or else the table slots are vacated |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1530 | * and the allocated memory released. (Except that the termios |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1531 | * and locked termios may be retained.) |
| 1532 | */ |
| 1533 | |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1534 | if (!try_module_get(driver->owner)) |
| 1535 | return ERR_PTR(-ENODEV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1536 | |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 1537 | tty = alloc_tty_struct(driver, idx); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1538 | if (!tty) { |
| 1539 | retval = -ENOMEM; |
| 1540 | goto err_module_put; |
| 1541 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1542 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1543 | tty_lock(tty); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1544 | retval = tty_driver_install_tty(driver, tty); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1545 | if (retval < 0) |
Peter Hurley | c8b710b | 2016-01-09 21:13:46 -0800 | [diff] [blame] | 1546 | goto err_free_tty; |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1547 | |
Jiri Slaby | 04831dc | 2012-06-04 13:35:36 +0200 | [diff] [blame] | 1548 | if (!tty->port) |
| 1549 | tty->port = driver->ports[idx]; |
| 1550 | |
Jiri Slaby | 5d4121c | 2012-08-17 14:27:52 +0200 | [diff] [blame] | 1551 | WARN_RATELIMIT(!tty->port, |
| 1552 | "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", |
| 1553 | __func__, tty->driver->name); |
| 1554 | |
Gaurav Kohli | 55eaecf | 2018-01-23 13:16:34 +0530 | [diff] [blame] | 1555 | retval = tty_ldisc_lock(tty, 5 * HZ); |
| 1556 | if (retval) |
| 1557 | goto err_release_lock; |
Jiri Slaby | 967fab6 | 2012-10-18 22:26:46 +0200 | [diff] [blame] | 1558 | tty->port->itty = tty; |
| 1559 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1560 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1561 | * Structures all installed ... call the ldisc open routines. |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1562 | * If we fail here just call release_tty to clean up. No need |
| 1563 | * to decrement the use counts, as release_tty doesn't care. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1564 | */ |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1565 | retval = tty_ldisc_setup(tty, tty->link); |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1566 | if (retval) |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1567 | goto err_release_tty; |
Gaurav Kohli | 55eaecf | 2018-01-23 13:16:34 +0530 | [diff] [blame] | 1568 | tty_ldisc_unlock(tty); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1569 | /* Return the tty locked so that it cannot vanish under the caller */ |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1570 | return tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1571 | |
Peter Hurley | c8b710b | 2016-01-09 21:13:46 -0800 | [diff] [blame] | 1572 | err_free_tty: |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1573 | tty_unlock(tty); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1574 | free_tty_struct(tty); |
| 1575 | err_module_put: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1576 | module_put(driver->owner); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1577 | return ERR_PTR(retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1578 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1579 | /* call the tty release_tty routine to clean out this slot */ |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1580 | err_release_tty: |
Gaurav Kohli | 55eaecf | 2018-01-23 13:16:34 +0530 | [diff] [blame] | 1581 | tty_ldisc_unlock(tty); |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 1582 | tty_info_ratelimited(tty, "ldisc open failed (%d), clearing slot %d\n", |
| 1583 | retval, idx); |
Gaurav Kohli | 55eaecf | 2018-01-23 13:16:34 +0530 | [diff] [blame] | 1584 | err_release_lock: |
| 1585 | tty_unlock(tty); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1586 | release_tty(tty, idx); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1587 | return ERR_PTR(retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1588 | } |
| 1589 | |
Peter Hurley | a3123fd | 2016-01-09 21:13:48 -0800 | [diff] [blame] | 1590 | static void tty_free_termios(struct tty_struct *tty) |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1591 | { |
| 1592 | struct ktermios *tp; |
| 1593 | int idx = tty->index; |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1594 | |
| 1595 | /* If the port is going to reset then it has no termios to save */ |
| 1596 | if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) |
| 1597 | return; |
| 1598 | |
| 1599 | /* Stash the termios data */ |
| 1600 | tp = tty->driver->termios[idx]; |
| 1601 | if (tp == NULL) { |
| 1602 | tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL); |
Peter Hurley | 2508065 | 2015-11-08 13:01:11 -0500 | [diff] [blame] | 1603 | if (tp == NULL) |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1604 | return; |
Dan Carpenter | 4ac5d70 | 2012-07-24 12:51:52 +0100 | [diff] [blame] | 1605 | tty->driver->termios[idx] = tp; |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1606 | } |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1607 | *tp = tty->termios; |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1608 | } |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1609 | |
Peter Hurley | a2965b7 | 2013-03-11 16:44:35 -0400 | [diff] [blame] | 1610 | /** |
Peter Hurley | 949aa64 | 2014-11-05 12:12:57 -0500 | [diff] [blame] | 1611 | * tty_flush_works - flush all works of a tty/pty pair |
| 1612 | * @tty: tty device to flush works for (or either end of a pty pair) |
Peter Hurley | a2965b7 | 2013-03-11 16:44:35 -0400 | [diff] [blame] | 1613 | * |
Peter Hurley | 949aa64 | 2014-11-05 12:12:57 -0500 | [diff] [blame] | 1614 | * Sync flush all works belonging to @tty (and the 'other' tty). |
Peter Hurley | a2965b7 | 2013-03-11 16:44:35 -0400 | [diff] [blame] | 1615 | */ |
| 1616 | static void tty_flush_works(struct tty_struct *tty) |
| 1617 | { |
| 1618 | flush_work(&tty->SAK_work); |
| 1619 | flush_work(&tty->hangup_work); |
Peter Hurley | 949aa64 | 2014-11-05 12:12:57 -0500 | [diff] [blame] | 1620 | if (tty->link) { |
| 1621 | flush_work(&tty->link->SAK_work); |
| 1622 | flush_work(&tty->link->hangup_work); |
| 1623 | } |
Peter Hurley | a2965b7 | 2013-03-11 16:44:35 -0400 | [diff] [blame] | 1624 | } |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1625 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1626 | /** |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1627 | * release_one_tty - release tty structure memory |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1628 | * @kref: kref of tty we are obliterating |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1629 | * |
| 1630 | * Releases memory associated with a tty structure, and clears out the |
| 1631 | * driver table slots. This function is called when a device is no longer |
| 1632 | * in use. It also gets called when setup of a device fails. |
| 1633 | * |
| 1634 | * Locking: |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1635 | * takes the file list lock internally when working on the list |
| 1636 | * of ttys that the driver keeps. |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1637 | * |
| 1638 | * This method gets called from a work queue so that the driver private |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1639 | * cleanup ops can sleep (needed for USB at least) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1640 | */ |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1641 | static void release_one_tty(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1642 | { |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1643 | struct tty_struct *tty = |
| 1644 | container_of(work, struct tty_struct, hangup_work); |
Alan Cox | 6f967f7 | 2008-10-13 10:37:36 +0100 | [diff] [blame] | 1645 | struct tty_driver *driver = tty->driver; |
Cyrill Gorcunov | b216df5 | 2014-08-08 00:26:15 +0400 | [diff] [blame] | 1646 | struct module *owner = driver->owner; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1647 | |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1648 | if (tty->ops->cleanup) |
| 1649 | tty->ops->cleanup(tty); |
| 1650 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1651 | tty->magic = 0; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 1652 | tty_driver_kref_put(driver); |
Cyrill Gorcunov | b216df5 | 2014-08-08 00:26:15 +0400 | [diff] [blame] | 1653 | module_put(owner); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1654 | |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 1655 | spin_lock(&tty->files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1656 | list_del_init(&tty->tty_files); |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 1657 | spin_unlock(&tty->files_lock); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1658 | |
Oleg Nesterov | 6da8d86 | 2010-04-02 18:05:12 +0200 | [diff] [blame] | 1659 | put_pid(tty->pgrp); |
| 1660 | put_pid(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1661 | free_tty_struct(tty); |
| 1662 | } |
| 1663 | |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1664 | static void queue_release_one_tty(struct kref *kref) |
| 1665 | { |
| 1666 | struct tty_struct *tty = container_of(kref, struct tty_struct, kref); |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1667 | |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1668 | /* The hangup queue is now free so we can reuse it rather than |
| 1669 | waste a chunk of memory for each port */ |
| 1670 | INIT_WORK(&tty->hangup_work, release_one_tty); |
| 1671 | schedule_work(&tty->hangup_work); |
| 1672 | } |
| 1673 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1674 | /** |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1675 | * tty_kref_put - release a tty kref |
| 1676 | * @tty: tty device |
| 1677 | * |
| 1678 | * Release a reference to a tty device and if need be let the kref |
| 1679 | * layer destruct the object for us |
| 1680 | */ |
| 1681 | |
| 1682 | void tty_kref_put(struct tty_struct *tty) |
| 1683 | { |
| 1684 | if (tty) |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1685 | kref_put(&tty->kref, queue_release_one_tty); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1686 | } |
| 1687 | EXPORT_SYMBOL(tty_kref_put); |
| 1688 | |
| 1689 | /** |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1690 | * release_tty - release tty structure memory |
| 1691 | * |
| 1692 | * Release both @tty and a possible linked partner (think pty pair), |
| 1693 | * and decrement the refcount of the backing module. |
| 1694 | * |
| 1695 | * Locking: |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1696 | * tty_mutex |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1697 | * takes the file list lock internally when working on the list |
| 1698 | * of ttys that the driver keeps. |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1699 | * |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1700 | */ |
| 1701 | static void release_tty(struct tty_struct *tty, int idx) |
| 1702 | { |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1703 | /* This should always be true but check for the moment */ |
| 1704 | WARN_ON(tty->index != idx); |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1705 | WARN_ON(!mutex_is_locked(&tty_mutex)); |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1706 | if (tty->ops->shutdown) |
| 1707 | tty->ops->shutdown(tty); |
| 1708 | tty_free_termios(tty); |
| 1709 | tty_driver_remove_tty(tty->driver, tty); |
Jiri Slaby | 967fab6 | 2012-10-18 22:26:46 +0200 | [diff] [blame] | 1710 | tty->port->itty = NULL; |
Peter Hurley | 64e377d | 2013-06-15 09:01:00 -0400 | [diff] [blame] | 1711 | if (tty->link) |
| 1712 | tty->link->port->itty = NULL; |
Peter Hurley | e176058 | 2015-10-17 16:36:23 -0400 | [diff] [blame] | 1713 | tty_buffer_cancel_work(tty->port); |
Sahara | d69cf85 | 2017-12-13 09:10:48 +0400 | [diff] [blame] | 1714 | if (tty->link) |
| 1715 | tty_buffer_cancel_work(tty->link->port); |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1716 | |
Markus Elfring | a211b1a | 2014-11-21 13:42:29 +0100 | [diff] [blame] | 1717 | tty_kref_put(tty->link); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1718 | tty_kref_put(tty); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1719 | } |
| 1720 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1721 | /** |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1722 | * tty_release_checks - check a tty before real release |
| 1723 | * @tty: tty to check |
| 1724 | * @o_tty: link of @tty (if any) |
| 1725 | * @idx: index of the tty |
| 1726 | * |
| 1727 | * Performs some paranoid checking before true release of the @tty. |
| 1728 | * This is a no-op unless TTY_PARANOIA_CHECK is defined. |
| 1729 | */ |
Peter Hurley | 359b9fb | 2014-11-05 12:12:59 -0500 | [diff] [blame] | 1730 | static int tty_release_checks(struct tty_struct *tty, int idx) |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1731 | { |
| 1732 | #ifdef TTY_PARANOIA_CHECK |
| 1733 | if (idx < 0 || idx >= tty->driver->num) { |
Peter Hurley | e2dfa3d | 2015-07-12 22:49:08 -0400 | [diff] [blame] | 1734 | tty_debug(tty, "bad idx %d\n", idx); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1735 | return -1; |
| 1736 | } |
| 1737 | |
| 1738 | /* not much to check for devpts */ |
| 1739 | if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) |
| 1740 | return 0; |
| 1741 | |
| 1742 | if (tty != tty->driver->ttys[idx]) { |
Peter Hurley | e2dfa3d | 2015-07-12 22:49:08 -0400 | [diff] [blame] | 1743 | tty_debug(tty, "bad driver table[%d] = %p\n", |
| 1744 | idx, tty->driver->ttys[idx]); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1745 | return -1; |
| 1746 | } |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1747 | if (tty->driver->other) { |
Peter Hurley | 359b9fb | 2014-11-05 12:12:59 -0500 | [diff] [blame] | 1748 | struct tty_struct *o_tty = tty->link; |
| 1749 | |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1750 | if (o_tty != tty->driver->other->ttys[idx]) { |
Peter Hurley | e2dfa3d | 2015-07-12 22:49:08 -0400 | [diff] [blame] | 1751 | tty_debug(tty, "bad other table[%d] = %p\n", |
| 1752 | idx, tty->driver->other->ttys[idx]); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1753 | return -1; |
| 1754 | } |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1755 | if (o_tty->link != tty) { |
Peter Hurley | e2dfa3d | 2015-07-12 22:49:08 -0400 | [diff] [blame] | 1756 | tty_debug(tty, "bad link = %p\n", o_tty->link); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1757 | return -1; |
| 1758 | } |
| 1759 | } |
| 1760 | #endif |
| 1761 | return 0; |
| 1762 | } |
| 1763 | |
| 1764 | /** |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1765 | * tty_release - vfs callback for close |
| 1766 | * @inode: inode of tty |
| 1767 | * @filp: file pointer for handle to tty |
| 1768 | * |
| 1769 | * Called the last time each file handle is closed that references |
| 1770 | * this tty. There may however be several such references. |
| 1771 | * |
| 1772 | * Locking: |
| 1773 | * Takes bkl. See tty_release_dev |
| 1774 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1775 | * Even releasing the tty structures is a tricky business.. We have |
| 1776 | * to be very careful that the structures are all released at the |
| 1777 | * same time, as interrupts might otherwise get the wrong pointers. |
| 1778 | * |
| 1779 | * WSH 09/09/97: rewritten to avoid some nasty race conditions that could |
| 1780 | * lead to double frees or releasing memory still in use. |
| 1781 | */ |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1782 | |
| 1783 | int tty_release(struct inode *inode, struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1784 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1785 | struct tty_struct *tty = file_tty(filp); |
Peter Hurley | 7ffb6da | 2014-11-05 12:13:00 -0500 | [diff] [blame] | 1786 | struct tty_struct *o_tty = NULL; |
| 1787 | int do_sleep, final; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1788 | int idx; |
Peter Hurley | 37b1645 | 2014-10-16 13:51:30 -0400 | [diff] [blame] | 1789 | long timeout = 0; |
Peter Hurley | 494c1ea | 2014-10-16 13:54:36 -0400 | [diff] [blame] | 1790 | int once = 1; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1791 | |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1792 | if (tty_paranoia_check(tty, inode, __func__)) |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1793 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1794 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1795 | tty_lock(tty); |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1796 | check_tty_count(tty, __func__); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1797 | |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 1798 | __tty_fasync(-1, filp, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1799 | |
| 1800 | idx = tty->index; |
Peter Hurley | 7ffb6da | 2014-11-05 12:13:00 -0500 | [diff] [blame] | 1801 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 1802 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 1803 | o_tty = tty->link; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1804 | |
Peter Hurley | 359b9fb | 2014-11-05 12:12:59 -0500 | [diff] [blame] | 1805 | if (tty_release_checks(tty, idx)) { |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1806 | tty_unlock(tty); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1807 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1808 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1809 | |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 1810 | tty_debug_hangup(tty, "releasing (count=%d)\n", tty->count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1811 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1812 | if (tty->ops->close) |
| 1813 | tty->ops->close(tty, filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1814 | |
Peter Hurley | 2aff5e2 | 2014-11-05 12:13:01 -0500 | [diff] [blame] | 1815 | /* If tty is pty master, lock the slave pty (stable lock order) */ |
| 1816 | tty_lock_slave(o_tty); |
| 1817 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1818 | /* |
| 1819 | * Sanity check: if tty->count is going to zero, there shouldn't be |
| 1820 | * any waiters on tty->read_wait or tty->write_wait. We test the |
| 1821 | * wait queues and kick everyone out _before_ actually starting to |
| 1822 | * close. This ensures that we won't block while releasing the tty |
| 1823 | * structure. |
| 1824 | * |
| 1825 | * The test for the o_tty closing is necessary, since the master and |
| 1826 | * slave sides may close in any order. If the slave side closes out |
| 1827 | * first, its count will be one, since the master side holds an open. |
Peter Hurley | 324c165 | 2014-11-05 12:12:56 -0500 | [diff] [blame] | 1828 | * Thus this test wouldn't be triggered at the time the slave closed, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1829 | * so we do it now. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1830 | */ |
| 1831 | while (1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1832 | do_sleep = 0; |
| 1833 | |
Peter Hurley | 324c165 | 2014-11-05 12:12:56 -0500 | [diff] [blame] | 1834 | if (tty->count <= 1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1835 | if (waitqueue_active(&tty->read_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1836 | wake_up_poll(&tty->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1837 | do_sleep++; |
| 1838 | } |
| 1839 | if (waitqueue_active(&tty->write_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1840 | wake_up_poll(&tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1841 | do_sleep++; |
| 1842 | } |
| 1843 | } |
Peter Hurley | 7ffb6da | 2014-11-05 12:13:00 -0500 | [diff] [blame] | 1844 | if (o_tty && o_tty->count <= 1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1845 | if (waitqueue_active(&o_tty->read_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1846 | wake_up_poll(&o_tty->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1847 | do_sleep++; |
| 1848 | } |
| 1849 | if (waitqueue_active(&o_tty->write_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1850 | wake_up_poll(&o_tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1851 | do_sleep++; |
| 1852 | } |
| 1853 | } |
| 1854 | if (!do_sleep) |
| 1855 | break; |
| 1856 | |
Peter Hurley | 494c1ea | 2014-10-16 13:54:36 -0400 | [diff] [blame] | 1857 | if (once) { |
| 1858 | once = 0; |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 1859 | tty_warn(tty, "read/write wait queue active!\n"); |
Peter Hurley | 494c1ea | 2014-10-16 13:54:36 -0400 | [diff] [blame] | 1860 | } |
Peter Hurley | 37b1645 | 2014-10-16 13:51:30 -0400 | [diff] [blame] | 1861 | schedule_timeout_killable(timeout); |
| 1862 | if (timeout < 120 * HZ) |
| 1863 | timeout = 2 * timeout + 1; |
| 1864 | else |
| 1865 | timeout = MAX_SCHEDULE_TIMEOUT; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1866 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1867 | |
Peter Hurley | 7ffb6da | 2014-11-05 12:13:00 -0500 | [diff] [blame] | 1868 | if (o_tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1869 | if (--o_tty->count < 0) { |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 1870 | tty_warn(tty, "bad slave count (%d)\n", o_tty->count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1871 | o_tty->count = 0; |
| 1872 | } |
| 1873 | } |
| 1874 | if (--tty->count < 0) { |
Peter Hurley | 339f36b | 2015-11-08 13:01:13 -0500 | [diff] [blame] | 1875 | tty_warn(tty, "bad tty->count (%d)\n", tty->count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1876 | tty->count = 0; |
| 1877 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1878 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1879 | /* |
| 1880 | * We've decremented tty->count, so we need to remove this file |
| 1881 | * descriptor off the tty->tty_files list; this serves two |
| 1882 | * purposes: |
| 1883 | * - check_tty_count sees the correct number of file descriptors |
| 1884 | * associated with this tty. |
| 1885 | * - do_tty_hangup no longer sees this file descriptor as |
| 1886 | * something that needs to be handled for hangups. |
| 1887 | */ |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1888 | tty_del_file(filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1889 | |
| 1890 | /* |
| 1891 | * Perform some housekeeping before deciding whether to return. |
| 1892 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1893 | * If _either_ side is closing, make sure there aren't any |
| 1894 | * processes that still think tty or o_tty is their controlling |
| 1895 | * tty. |
| 1896 | */ |
Peter Hurley | 324c165 | 2014-11-05 12:12:56 -0500 | [diff] [blame] | 1897 | if (!tty->count) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1898 | read_lock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1899 | session_clear_tty(tty->session); |
Peter Hurley | 7ffb6da | 2014-11-05 12:13:00 -0500 | [diff] [blame] | 1900 | if (o_tty) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1901 | session_clear_tty(o_tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1902 | read_unlock(&tasklist_lock); |
| 1903 | } |
| 1904 | |
Peter Hurley | 324c165 | 2014-11-05 12:12:56 -0500 | [diff] [blame] | 1905 | /* check whether both sides are closing ... */ |
Peter Hurley | 7ffb6da | 2014-11-05 12:13:00 -0500 | [diff] [blame] | 1906 | final = !tty->count && !(o_tty && o_tty->count); |
Peter Hurley | 324c165 | 2014-11-05 12:12:56 -0500 | [diff] [blame] | 1907 | |
Peter Hurley | 2aff5e2 | 2014-11-05 12:13:01 -0500 | [diff] [blame] | 1908 | tty_unlock_slave(o_tty); |
| 1909 | tty_unlock(tty); |
| 1910 | |
Peter Hurley | 0498070 | 2014-11-05 12:12:52 -0500 | [diff] [blame] | 1911 | /* At this point, the tty->count == 0 should ensure a dead tty |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1912 | cannot be re-opened by a racing opener */ |
Paul Fulghum | da96582 | 2006-02-14 13:53:00 -0800 | [diff] [blame] | 1913 | |
Peter Hurley | 324c165 | 2014-11-05 12:12:56 -0500 | [diff] [blame] | 1914 | if (!final) |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1915 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1916 | |
Peter Hurley | accff79 | 2015-07-12 22:49:09 -0400 | [diff] [blame] | 1917 | tty_debug_hangup(tty, "final close\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1918 | /* |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1919 | * Ask the line discipline code to release its structures |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1920 | */ |
Peter Hurley | 62462ae | 2014-11-05 12:12:58 -0500 | [diff] [blame] | 1921 | tty_ldisc_release(tty); |
Peter Hurley | a2965b7 | 2013-03-11 16:44:35 -0400 | [diff] [blame] | 1922 | |
| 1923 | /* Wait for pending work before tty destruction commmences */ |
| 1924 | tty_flush_works(tty); |
Peter Hurley | a2965b7 | 2013-03-11 16:44:35 -0400 | [diff] [blame] | 1925 | |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 1926 | tty_debug_hangup(tty, "freeing structure\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1927 | /* |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1928 | * The release_tty function takes care of the details of clearing |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1929 | * the slots and preserving the termios structure. The tty_unlock_pair |
| 1930 | * should be safe as we keep a kref while the tty is locked (so the |
| 1931 | * unlock never unlocks a freed tty). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1932 | */ |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1933 | mutex_lock(&tty_mutex); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1934 | release_tty(tty, idx); |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1935 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1936 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1937 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1938 | } |
| 1939 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1940 | /** |
Peter Hurley | 52494ee | 2014-11-05 12:12:50 -0500 | [diff] [blame] | 1941 | * tty_open_current_tty - get locked tty of current task |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1942 | * @device: device number |
| 1943 | * @filp: file pointer to tty |
Peter Hurley | 52494ee | 2014-11-05 12:12:50 -0500 | [diff] [blame] | 1944 | * @return: locked tty of the current task iff @device is /dev/tty |
| 1945 | * |
| 1946 | * Performs a re-open of the current task's controlling tty. |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1947 | * |
| 1948 | * We cannot return driver and index like for the other nodes because |
| 1949 | * devpts will not work then. It expects inodes to be from devpts FS. |
| 1950 | */ |
| 1951 | static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) |
| 1952 | { |
| 1953 | struct tty_struct *tty; |
Peter Hurley | 52494ee | 2014-11-05 12:12:50 -0500 | [diff] [blame] | 1954 | int retval; |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1955 | |
| 1956 | if (device != MKDEV(TTYAUX_MAJOR, 0)) |
| 1957 | return NULL; |
| 1958 | |
| 1959 | tty = get_current_tty(); |
| 1960 | if (!tty) |
| 1961 | return ERR_PTR(-ENXIO); |
| 1962 | |
| 1963 | filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ |
| 1964 | /* noctty = 1; */ |
Peter Hurley | 52494ee | 2014-11-05 12:12:50 -0500 | [diff] [blame] | 1965 | tty_lock(tty); |
| 1966 | tty_kref_put(tty); /* safe to drop the kref now */ |
| 1967 | |
| 1968 | retval = tty_reopen(tty); |
| 1969 | if (retval < 0) { |
| 1970 | tty_unlock(tty); |
| 1971 | tty = ERR_PTR(retval); |
| 1972 | } |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1973 | return tty; |
| 1974 | } |
| 1975 | |
| 1976 | /** |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1977 | * tty_lookup_driver - lookup a tty driver for a given device file |
| 1978 | * @device: device number |
| 1979 | * @filp: file pointer to tty |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1980 | * @index: index for the device in the @return driver |
| 1981 | * @return: driver for this inode (with increased refcount) |
| 1982 | * |
| 1983 | * If @return is not erroneous, the caller is responsible to decrement the |
| 1984 | * refcount by tty_driver_kref_put. |
| 1985 | * |
| 1986 | * Locking: tty_mutex protects get_tty_driver |
| 1987 | */ |
| 1988 | static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp, |
Peter Hurley | 11e1d4a | 2016-01-09 21:13:52 -0800 | [diff] [blame] | 1989 | int *index) |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1990 | { |
| 1991 | struct tty_driver *driver; |
| 1992 | |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1993 | switch (device) { |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1994 | #ifdef CONFIG_VT |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1995 | case MKDEV(TTY_MAJOR, 0): { |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1996 | extern struct tty_driver *console_driver; |
| 1997 | driver = tty_driver_kref_get(console_driver); |
| 1998 | *index = fg_console; |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1999 | break; |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 2000 | } |
| 2001 | #endif |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 2002 | case MKDEV(TTYAUX_MAJOR, 1): { |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 2003 | struct tty_driver *console_driver = console_device(index); |
| 2004 | if (console_driver) { |
| 2005 | driver = tty_driver_kref_get(console_driver); |
| 2006 | if (driver) { |
| 2007 | /* Don't let /dev/console block */ |
| 2008 | filp->f_flags |= O_NONBLOCK; |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 2009 | break; |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 2010 | } |
| 2011 | } |
| 2012 | return ERR_PTR(-ENODEV); |
| 2013 | } |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 2014 | default: |
| 2015 | driver = get_tty_driver(device, index); |
| 2016 | if (!driver) |
| 2017 | return ERR_PTR(-ENODEV); |
| 2018 | break; |
| 2019 | } |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 2020 | return driver; |
| 2021 | } |
| 2022 | |
| 2023 | /** |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2024 | * tty_open_by_driver - open a tty device |
| 2025 | * @device: dev_t of device to open |
| 2026 | * @inode: inode of device file |
| 2027 | * @filp: file pointer to tty |
| 2028 | * |
| 2029 | * Performs the driver lookup, checks for a reopen, or otherwise |
| 2030 | * performs the first-time tty initialization. |
| 2031 | * |
| 2032 | * Returns the locked initialized or re-opened &tty_struct |
| 2033 | * |
| 2034 | * Claims the global tty_mutex to serialize: |
| 2035 | * - concurrent first-time tty initialization |
| 2036 | * - concurrent tty driver removal w/ lookup |
| 2037 | * - concurrent tty removal from driver table |
| 2038 | */ |
| 2039 | static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode, |
| 2040 | struct file *filp) |
| 2041 | { |
| 2042 | struct tty_struct *tty; |
| 2043 | struct tty_driver *driver = NULL; |
| 2044 | int index = -1; |
| 2045 | int retval; |
| 2046 | |
| 2047 | mutex_lock(&tty_mutex); |
| 2048 | driver = tty_lookup_driver(device, filp, &index); |
| 2049 | if (IS_ERR(driver)) { |
| 2050 | mutex_unlock(&tty_mutex); |
| 2051 | return ERR_CAST(driver); |
| 2052 | } |
| 2053 | |
| 2054 | /* check whether we're reopening an existing tty */ |
Linus Torvalds | 8ead9dd | 2016-04-25 20:04:08 -0700 | [diff] [blame] | 2055 | tty = tty_driver_lookup_tty(driver, filp, index); |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2056 | if (IS_ERR(tty)) { |
| 2057 | mutex_unlock(&tty_mutex); |
| 2058 | goto out; |
| 2059 | } |
| 2060 | |
| 2061 | if (tty) { |
| 2062 | mutex_unlock(&tty_mutex); |
| 2063 | retval = tty_lock_interruptible(tty); |
Peter Hurley | 5e00bbf | 2016-03-31 17:47:07 -0700 | [diff] [blame] | 2064 | tty_kref_put(tty); /* drop kref from tty_driver_lookup_tty() */ |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2065 | if (retval) { |
| 2066 | if (retval == -EINTR) |
| 2067 | retval = -ERESTARTSYS; |
| 2068 | tty = ERR_PTR(retval); |
| 2069 | goto out; |
| 2070 | } |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2071 | retval = tty_reopen(tty); |
| 2072 | if (retval < 0) { |
| 2073 | tty_unlock(tty); |
| 2074 | tty = ERR_PTR(retval); |
| 2075 | } |
| 2076 | } else { /* Returns with the tty_lock held for now */ |
| 2077 | tty = tty_init_dev(driver, index); |
| 2078 | mutex_unlock(&tty_mutex); |
| 2079 | } |
| 2080 | out: |
| 2081 | tty_driver_kref_put(driver); |
| 2082 | return tty; |
| 2083 | } |
| 2084 | |
| 2085 | /** |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2086 | * tty_open - open a tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2087 | * @inode: inode of device file |
| 2088 | * @filp: file pointer to tty |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2089 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2090 | * tty_open and tty_release keep up the tty count that contains the |
| 2091 | * number of opens done on a tty. We cannot use the inode-count, as |
| 2092 | * different inodes might point to the same tty. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2093 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2094 | * Open-counting is needed for pty masters, as well as for keeping |
| 2095 | * track of serial lines: DTR is dropped when the last close happens. |
| 2096 | * (This is not done solely through tty->count, now. - Ted 1/27/92) |
| 2097 | * |
| 2098 | * The termios state of a pty is reset on first open so that |
| 2099 | * settings don't persist across reuse. |
| 2100 | * |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 2101 | * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev. |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2102 | * tty->count should protect the rest. |
| 2103 | * ->siglock protects ->signal/->sighand |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2104 | * |
| 2105 | * Note: the tty_unlock/lock cases without a ref are only safe due to |
| 2106 | * tty_mutex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2107 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2108 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2109 | static int tty_open(struct inode *inode, struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2110 | { |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 2111 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2112 | int noctty, retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2113 | dev_t device = inode->i_rdev; |
Andrew Morton | 846c151 | 2009-04-02 16:56:36 -0700 | [diff] [blame] | 2114 | unsigned saved_flags = filp->f_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2115 | |
| 2116 | nonseekable_open(inode, filp); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2117 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2118 | retry_open: |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 2119 | retval = tty_alloc_file(filp); |
| 2120 | if (retval) |
| 2121 | return -ENOMEM; |
| 2122 | |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 2123 | tty = tty_open_current_tty(device, filp); |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2124 | if (!tty) |
| 2125 | tty = tty_open_by_driver(device, inode, filp); |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 2126 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2127 | if (IS_ERR(tty)) { |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2128 | tty_free_file(filp); |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 2129 | retval = PTR_ERR(tty); |
Peter Hurley | 7f22f6c | 2016-01-09 21:13:45 -0800 | [diff] [blame] | 2130 | if (retval != -EAGAIN || signal_pending(current)) |
Peter Hurley | d6203d0 | 2016-01-09 21:13:53 -0800 | [diff] [blame] | 2131 | return retval; |
Peter Hurley | 7f22f6c | 2016-01-09 21:13:45 -0800 | [diff] [blame] | 2132 | schedule(); |
| 2133 | goto retry_open; |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2134 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2135 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 2136 | tty_add_file(tty, filp); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2137 | |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 2138 | check_tty_count(tty, __func__); |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 2139 | tty_debug_hangup(tty, "opening (count=%d)\n", tty->count); |
Peter Hurley | accff79 | 2015-07-12 22:49:09 -0400 | [diff] [blame] | 2140 | |
Herton Ronaldo Krzesinski | 909bc77 | 2011-03-31 15:35:31 -0300 | [diff] [blame] | 2141 | if (tty->ops->open) |
| 2142 | retval = tty->ops->open(tty, filp); |
| 2143 | else |
| 2144 | retval = -ENODEV; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2145 | filp->f_flags = saved_flags; |
| 2146 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2147 | if (retval) { |
Peter Hurley | d435cef | 2015-11-08 13:01:19 -0500 | [diff] [blame] | 2148 | tty_debug_hangup(tty, "open error %d, releasing\n", retval); |
Peter Hurley | accff79 | 2015-07-12 22:49:09 -0400 | [diff] [blame] | 2149 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2150 | tty_unlock(tty); /* need to call tty_release without BTM */ |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2151 | tty_release(inode, filp); |
Arnd Bergmann | 64ba3dc | 2010-06-01 22:53:02 +0200 | [diff] [blame] | 2152 | if (retval != -ERESTARTSYS) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2153 | return retval; |
Arnd Bergmann | 64ba3dc | 2010-06-01 22:53:02 +0200 | [diff] [blame] | 2154 | |
| 2155 | if (signal_pending(current)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2156 | return retval; |
Arnd Bergmann | 64ba3dc | 2010-06-01 22:53:02 +0200 | [diff] [blame] | 2157 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2158 | schedule(); |
| 2159 | /* |
| 2160 | * Need to reset f_op in case a hangup happened. |
| 2161 | */ |
Peter Hurley | 1256937 | 2014-11-05 12:26:24 -0500 | [diff] [blame] | 2162 | if (tty_hung_up_p(filp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2163 | filp->f_op = &tty_fops; |
| 2164 | goto retry_open; |
| 2165 | } |
Peter Hurley | d4855e1 | 2013-11-19 08:46:27 -0500 | [diff] [blame] | 2166 | clear_bit(TTY_HUPPED, &tty->flags); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2167 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2168 | |
Peter Hurley | 2c411c1 | 2014-10-16 14:59:47 -0400 | [diff] [blame] | 2169 | read_lock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2170 | spin_lock_irq(¤t->sighand->siglock); |
Peter Hurley | 11e1d4a | 2016-01-09 21:13:52 -0800 | [diff] [blame] | 2171 | noctty = (filp->f_flags & O_NOCTTY) || |
Peter Hurley | da5a0fc | 2016-03-31 17:05:30 -0700 | [diff] [blame] | 2172 | (IS_ENABLED(CONFIG_VT) && device == MKDEV(TTY_MAJOR, 0)) || |
Peter Hurley | 11e1d4a | 2016-01-09 21:13:52 -0800 | [diff] [blame] | 2173 | device == MKDEV(TTYAUX_MAJOR, 1) || |
| 2174 | (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 2175 | tty->driver->subtype == PTY_TYPE_MASTER); |
| 2176 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2177 | if (!noctty && |
| 2178 | current->signal->leader && |
| 2179 | !current->signal->tty && |
Jann Horn | 0c556271 | 2015-10-04 19:29:12 +0200 | [diff] [blame] | 2180 | tty->session == NULL) { |
| 2181 | /* |
| 2182 | * Don't let a process that only has write access to the tty |
| 2183 | * obtain the privileges associated with having a tty as |
| 2184 | * controlling terminal (being able to reopen it with full |
| 2185 | * access through /dev/tty, being able to perform pushback). |
| 2186 | * Many distributions set the group of all ttys to "tty" and |
| 2187 | * grant write-only access to all terminals for setgid tty |
| 2188 | * binaries, which should not imply full privileges on all ttys. |
| 2189 | * |
| 2190 | * This could theoretically break old code that performs open() |
| 2191 | * on a write-only file descriptor. In that case, it might be |
| 2192 | * necessary to also permit this if |
| 2193 | * inode_permission(inode, MAY_READ) == 0. |
| 2194 | */ |
| 2195 | if (filp->f_mode & FMODE_READ) |
| 2196 | __proc_set_tty(tty); |
| 2197 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2198 | spin_unlock_irq(¤t->sighand->siglock); |
Peter Hurley | 2c411c1 | 2014-10-16 14:59:47 -0400 | [diff] [blame] | 2199 | read_unlock(&tasklist_lock); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2200 | tty_unlock(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2201 | return 0; |
| 2202 | } |
| 2203 | |
Jonathan Corbet | 39d95b9 | 2008-05-16 09:10:50 -0600 | [diff] [blame] | 2204 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2205 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2206 | /** |
| 2207 | * tty_poll - check tty status |
| 2208 | * @filp: file being polled |
| 2209 | * @wait: poll wait structures to update |
| 2210 | * |
| 2211 | * Call the line discipline polling method to obtain the poll |
| 2212 | * status of the device. |
| 2213 | * |
| 2214 | * Locking: locks called line discipline but ldisc poll method |
| 2215 | * may be re-entered freely by other callers. |
| 2216 | */ |
| 2217 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2218 | static unsigned int tty_poll(struct file *filp, poll_table *wait) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2219 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2220 | struct tty_struct *tty = file_tty(filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2221 | struct tty_ldisc *ld; |
| 2222 | int ret = 0; |
| 2223 | |
Al Viro | 6131ffa | 2013-02-27 16:59:05 -0500 | [diff] [blame] | 2224 | if (tty_paranoia_check(tty, file_inode(filp), "tty_poll")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2225 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2226 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2227 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 2228 | if (!ld) |
| 2229 | return hung_up_tty_poll(filp, wait); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2230 | if (ld->ops->poll) |
Peter Hurley | c961bfb | 2014-11-05 12:26:25 -0500 | [diff] [blame] | 2231 | ret = ld->ops->poll(tty, filp, wait); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2232 | tty_ldisc_deref(ld); |
| 2233 | return ret; |
| 2234 | } |
| 2235 | |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 2236 | static int __tty_fasync(int fd, struct file *filp, int on) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2237 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2238 | struct tty_struct *tty = file_tty(filp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2239 | unsigned long flags; |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2240 | int retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2241 | |
Al Viro | 6131ffa | 2013-02-27 16:59:05 -0500 | [diff] [blame] | 2242 | if (tty_paranoia_check(tty, file_inode(filp), "tty_fasync")) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2243 | goto out; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2244 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2245 | retval = fasync_helper(fd, filp, on, &tty->fasync); |
| 2246 | if (retval <= 0) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2247 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2248 | |
| 2249 | if (on) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2250 | enum pid_type type; |
| 2251 | struct pid *pid; |
Peter Hurley | f6c8dbe | 2013-06-15 07:28:28 -0400 | [diff] [blame] | 2252 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2253 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2254 | if (tty->pgrp) { |
| 2255 | pid = tty->pgrp; |
| 2256 | type = PIDTYPE_PGID; |
| 2257 | } else { |
| 2258 | pid = task_pid(current); |
| 2259 | type = PIDTYPE_PID; |
| 2260 | } |
Linus Torvalds | 80e1e82 | 2010-02-07 10:11:23 -0800 | [diff] [blame] | 2261 | get_pid(pid); |
Greg Kroah-Hartman | 7036251 | 2009-12-17 07:07:19 -0800 | [diff] [blame] | 2262 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Jeff Layton | e0b93ed | 2014-08-22 11:27:32 -0400 | [diff] [blame] | 2263 | __f_setown(filp, pid, type, 0); |
Linus Torvalds | 80e1e82 | 2010-02-07 10:11:23 -0800 | [diff] [blame] | 2264 | put_pid(pid); |
Jeff Layton | e0b93ed | 2014-08-22 11:27:32 -0400 | [diff] [blame] | 2265 | retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2266 | } |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2267 | out: |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 2268 | return retval; |
| 2269 | } |
| 2270 | |
| 2271 | static int tty_fasync(int fd, struct file *filp, int on) |
| 2272 | { |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2273 | struct tty_struct *tty = file_tty(filp); |
Peter Hurley | a8f3a29 | 2016-01-09 21:45:11 -0800 | [diff] [blame] | 2274 | int retval = -ENOTTY; |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2275 | |
| 2276 | tty_lock(tty); |
Peter Hurley | a8f3a29 | 2016-01-09 21:45:11 -0800 | [diff] [blame] | 2277 | if (!tty_hung_up_p(filp)) |
| 2278 | retval = __tty_fasync(fd, filp, on); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2279 | tty_unlock(tty); |
| 2280 | |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2281 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2282 | } |
| 2283 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2284 | /** |
| 2285 | * tiocsti - fake input character |
| 2286 | * @tty: tty to fake input into |
| 2287 | * @p: pointer to character |
| 2288 | * |
Robert P. J. Day | 3a4fa0a | 2007-10-19 23:10:43 +0200 | [diff] [blame] | 2289 | * Fake input to a tty device. Does the necessary locking and |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2290 | * input management. |
| 2291 | * |
| 2292 | * FIXME: does not honour flow control ?? |
| 2293 | * |
| 2294 | * Locking: |
Peter Hurley | 137084b | 2013-06-15 07:04:46 -0400 | [diff] [blame] | 2295 | * Called functions take tty_ldiscs_lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2296 | * current->signal->tty check is safe without locks |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2297 | * |
| 2298 | * FIXME: may race normal receive processing |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2299 | */ |
| 2300 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2301 | static int tiocsti(struct tty_struct *tty, char __user *p) |
| 2302 | { |
| 2303 | char ch, mbz = 0; |
| 2304 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2305 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2306 | if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) |
| 2307 | return -EPERM; |
| 2308 | if (get_user(ch, p)) |
| 2309 | return -EFAULT; |
Al Viro | 1e64174 | 2008-12-09 09:23:33 +0000 | [diff] [blame] | 2310 | tty_audit_tiocsti(tty, ch); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2311 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 2312 | if (!ld) |
| 2313 | return -EIO; |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2314 | ld->ops->receive_buf(tty, &ch, &mbz, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2315 | tty_ldisc_deref(ld); |
| 2316 | return 0; |
| 2317 | } |
| 2318 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2319 | /** |
| 2320 | * tiocgwinsz - implement window query ioctl |
| 2321 | * @tty; tty |
| 2322 | * @arg: user buffer for result |
| 2323 | * |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2324 | * Copies the kernel idea of the window size into the user buffer. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2325 | * |
Peter Hurley | dee4a0b | 2013-07-24 16:43:51 -0400 | [diff] [blame] | 2326 | * Locking: tty->winsize_mutex is taken to ensure the winsize data |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2327 | * is consistent. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2328 | */ |
| 2329 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2330 | static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2331 | { |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2332 | int err; |
| 2333 | |
Peter Hurley | dee4a0b | 2013-07-24 16:43:51 -0400 | [diff] [blame] | 2334 | mutex_lock(&tty->winsize_mutex); |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2335 | err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); |
Peter Hurley | dee4a0b | 2013-07-24 16:43:51 -0400 | [diff] [blame] | 2336 | mutex_unlock(&tty->winsize_mutex); |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2337 | |
| 2338 | return err ? -EFAULT: 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2339 | } |
| 2340 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2341 | /** |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2342 | * tty_do_resize - resize event |
| 2343 | * @tty: tty being resized |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2344 | * @rows: rows (character) |
| 2345 | * @cols: cols (character) |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2346 | * |
Daniel Mack | 3ad2f3f | 2010-02-03 08:01:28 +0800 | [diff] [blame] | 2347 | * Update the termios variables and send the necessary signals to |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2348 | * peform a terminal resize correctly |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2349 | */ |
| 2350 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2351 | int tty_do_resize(struct tty_struct *tty, struct winsize *ws) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2352 | { |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2353 | struct pid *pgrp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2354 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2355 | /* Lock the tty */ |
Peter Hurley | dee4a0b | 2013-07-24 16:43:51 -0400 | [diff] [blame] | 2356 | mutex_lock(&tty->winsize_mutex); |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2357 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) |
Alan Cox | ca9bda0 | 2006-09-29 02:00:03 -0700 | [diff] [blame] | 2358 | goto done; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2359 | |
Peter Hurley | 5b23954 | 2014-10-16 14:59:45 -0400 | [diff] [blame] | 2360 | /* Signal the foreground process group */ |
| 2361 | pgrp = tty_get_pgrp(tty); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2362 | if (pgrp) |
| 2363 | kill_pgrp(pgrp, SIGWINCH, 1); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2364 | put_pid(pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2365 | |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2366 | tty->winsize = *ws; |
Alan Cox | ca9bda0 | 2006-09-29 02:00:03 -0700 | [diff] [blame] | 2367 | done: |
Peter Hurley | dee4a0b | 2013-07-24 16:43:51 -0400 | [diff] [blame] | 2368 | mutex_unlock(&tty->winsize_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2369 | return 0; |
| 2370 | } |
Martin Schwidefsky | 4d334fd | 2013-01-04 14:55:13 +0100 | [diff] [blame] | 2371 | EXPORT_SYMBOL(tty_do_resize); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2372 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2373 | /** |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2374 | * tiocswinsz - implement window size set ioctl |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2375 | * @tty; tty side of tty |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2376 | * @arg: user buffer for result |
| 2377 | * |
| 2378 | * Copies the user idea of the window size to the kernel. Traditionally |
| 2379 | * this is just advisory information but for the Linux console it |
| 2380 | * actually has driver level meaning and triggers a VC resize. |
| 2381 | * |
| 2382 | * Locking: |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2383 | * Driver dependent. The default do_resize method takes the |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2384 | * tty termios mutex and ctrl_lock. The console takes its own lock |
| 2385 | * then calls into the default method. |
| 2386 | */ |
| 2387 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2388 | static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2389 | { |
| 2390 | struct winsize tmp_ws; |
| 2391 | if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) |
| 2392 | return -EFAULT; |
| 2393 | |
| 2394 | if (tty->ops->resize) |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2395 | return tty->ops->resize(tty, &tmp_ws); |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2396 | else |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2397 | return tty_do_resize(tty, &tmp_ws); |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2398 | } |
| 2399 | |
| 2400 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2401 | * tioccons - allow admin to move logical console |
| 2402 | * @file: the file to become console |
| 2403 | * |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2404 | * Allow the administrator to move the redirected console device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2405 | * |
| 2406 | * Locking: uses redirect_lock to guard the redirect information |
| 2407 | */ |
| 2408 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2409 | static int tioccons(struct file *file) |
| 2410 | { |
| 2411 | if (!capable(CAP_SYS_ADMIN)) |
| 2412 | return -EPERM; |
| 2413 | if (file->f_op->write == redirected_tty_write) { |
| 2414 | struct file *f; |
| 2415 | spin_lock(&redirect_lock); |
| 2416 | f = redirect; |
| 2417 | redirect = NULL; |
| 2418 | spin_unlock(&redirect_lock); |
| 2419 | if (f) |
| 2420 | fput(f); |
| 2421 | return 0; |
| 2422 | } |
| 2423 | spin_lock(&redirect_lock); |
| 2424 | if (redirect) { |
| 2425 | spin_unlock(&redirect_lock); |
| 2426 | return -EBUSY; |
| 2427 | } |
Al Viro | cb0942b | 2012-08-27 14:48:26 -0400 | [diff] [blame] | 2428 | redirect = get_file(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2429 | spin_unlock(&redirect_lock); |
| 2430 | return 0; |
| 2431 | } |
| 2432 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2433 | /** |
| 2434 | * fionbio - non blocking ioctl |
| 2435 | * @file: file to set blocking value |
| 2436 | * @p: user parameter |
| 2437 | * |
| 2438 | * Historical tty interfaces had a blocking control ioctl before |
| 2439 | * the generic functionality existed. This piece of history is preserved |
| 2440 | * in the expected tty API of posix OS's. |
| 2441 | * |
Alan Cox | 6146b9a | 2009-09-19 13:13:19 -0700 | [diff] [blame] | 2442 | * Locking: none, the open file handle ensures it won't go away. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2443 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2444 | |
| 2445 | static int fionbio(struct file *file, int __user *p) |
| 2446 | { |
| 2447 | int nonblock; |
| 2448 | |
| 2449 | if (get_user(nonblock, p)) |
| 2450 | return -EFAULT; |
| 2451 | |
Jonathan Corbet | db1dd4d | 2009-02-06 15:25:24 -0700 | [diff] [blame] | 2452 | spin_lock(&file->f_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2453 | if (nonblock) |
| 2454 | file->f_flags |= O_NONBLOCK; |
| 2455 | else |
| 2456 | file->f_flags &= ~O_NONBLOCK; |
Jonathan Corbet | db1dd4d | 2009-02-06 15:25:24 -0700 | [diff] [blame] | 2457 | spin_unlock(&file->f_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2458 | return 0; |
| 2459 | } |
| 2460 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2461 | /** |
| 2462 | * tiocsctty - set controlling tty |
| 2463 | * @tty: tty structure |
| 2464 | * @arg: user argument |
| 2465 | * |
| 2466 | * This ioctl is used to manage job control. It permits a session |
| 2467 | * leader to set this tty as the controlling tty for the session. |
| 2468 | * |
| 2469 | * Locking: |
Peter Hurley | e218eb3 | 2014-10-16 14:59:49 -0400 | [diff] [blame] | 2470 | * Takes tty_lock() to serialize proc_set_tty() for this tty |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2471 | * Takes tasklist_lock internally to walk sessions |
| 2472 | * Takes ->siglock() when updating signal->tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2473 | */ |
| 2474 | |
Jann Horn | 0c556271 | 2015-10-04 19:29:12 +0200 | [diff] [blame] | 2475 | static int tiocsctty(struct tty_struct *tty, struct file *file, int arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2476 | { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2477 | int ret = 0; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2478 | |
Peter Hurley | e218eb3 | 2014-10-16 14:59:49 -0400 | [diff] [blame] | 2479 | tty_lock(tty); |
Peter Hurley | 2c411c1 | 2014-10-16 14:59:47 -0400 | [diff] [blame] | 2480 | read_lock(&tasklist_lock); |
| 2481 | |
| 2482 | if (current->signal->leader && (task_session(current) == tty->session)) |
| 2483 | goto unlock; |
| 2484 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2485 | /* |
| 2486 | * The process must be a session leader and |
| 2487 | * not have a controlling tty already. |
| 2488 | */ |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2489 | if (!current->signal->leader || current->signal->tty) { |
| 2490 | ret = -EPERM; |
| 2491 | goto unlock; |
| 2492 | } |
| 2493 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2494 | if (tty->session) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2495 | /* |
| 2496 | * This tty is already the controlling |
| 2497 | * tty for another session group! |
| 2498 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2499 | if (arg == 1 && capable(CAP_SYS_ADMIN)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2500 | /* |
| 2501 | * Steal it away |
| 2502 | */ |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2503 | session_clear_tty(tty->session); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2504 | } else { |
| 2505 | ret = -EPERM; |
| 2506 | goto unlock; |
| 2507 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2508 | } |
Jann Horn | 0c556271 | 2015-10-04 19:29:12 +0200 | [diff] [blame] | 2509 | |
| 2510 | /* See the comment in tty_open(). */ |
| 2511 | if ((file->f_mode & FMODE_READ) == 0 && !capable(CAP_SYS_ADMIN)) { |
| 2512 | ret = -EPERM; |
| 2513 | goto unlock; |
| 2514 | } |
| 2515 | |
Peter Hurley | bce65f1 | 2014-10-16 14:59:43 -0400 | [diff] [blame] | 2516 | proc_set_tty(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2517 | unlock: |
Peter Hurley | 2c411c1 | 2014-10-16 14:59:47 -0400 | [diff] [blame] | 2518 | read_unlock(&tasklist_lock); |
Peter Hurley | e218eb3 | 2014-10-16 14:59:49 -0400 | [diff] [blame] | 2519 | tty_unlock(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2520 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2521 | } |
| 2522 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2523 | /** |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2524 | * tty_get_pgrp - return a ref counted pgrp pid |
| 2525 | * @tty: tty to read |
| 2526 | * |
| 2527 | * Returns a refcounted instance of the pid struct for the process |
| 2528 | * group controlling the tty. |
| 2529 | */ |
| 2530 | |
| 2531 | struct pid *tty_get_pgrp(struct tty_struct *tty) |
| 2532 | { |
| 2533 | unsigned long flags; |
| 2534 | struct pid *pgrp; |
| 2535 | |
| 2536 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 2537 | pgrp = get_pid(tty->pgrp); |
| 2538 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 2539 | |
| 2540 | return pgrp; |
| 2541 | } |
| 2542 | EXPORT_SYMBOL_GPL(tty_get_pgrp); |
| 2543 | |
Peter Hurley | e1c2296 | 2014-10-16 14:59:48 -0400 | [diff] [blame] | 2544 | /* |
| 2545 | * This checks not only the pgrp, but falls back on the pid if no |
| 2546 | * satisfactory pgrp is found. I dunno - gdb doesn't work correctly |
| 2547 | * without this... |
| 2548 | * |
| 2549 | * The caller must hold rcu lock or the tasklist lock. |
| 2550 | */ |
| 2551 | static struct pid *session_of_pgrp(struct pid *pgrp) |
| 2552 | { |
| 2553 | struct task_struct *p; |
| 2554 | struct pid *sid = NULL; |
| 2555 | |
| 2556 | p = pid_task(pgrp, PIDTYPE_PGID); |
| 2557 | if (p == NULL) |
| 2558 | p = pid_task(pgrp, PIDTYPE_PID); |
| 2559 | if (p != NULL) |
| 2560 | sid = task_session(p); |
| 2561 | |
| 2562 | return sid; |
| 2563 | } |
| 2564 | |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2565 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2566 | * tiocgpgrp - get process group |
| 2567 | * @tty: tty passed by user |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2568 | * @real_tty: tty side of the tty passed by the user if a pty else the tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2569 | * @p: returned pid |
| 2570 | * |
| 2571 | * Obtain the process group of the tty. If there is no process group |
| 2572 | * return an error. |
| 2573 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2574 | * Locking: none. Reference to current->signal->tty is safe. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2575 | */ |
| 2576 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2577 | static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2578 | { |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2579 | struct pid *pid; |
| 2580 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2581 | /* |
| 2582 | * (tty == real_tty) is a cheap way of |
| 2583 | * testing if the tty is NOT a master pty. |
| 2584 | */ |
| 2585 | if (tty == real_tty && current->signal->tty != real_tty) |
| 2586 | return -ENOTTY; |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2587 | pid = tty_get_pgrp(real_tty); |
| 2588 | ret = put_user(pid_vnr(pid), p); |
| 2589 | put_pid(pid); |
| 2590 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2591 | } |
| 2592 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2593 | /** |
| 2594 | * tiocspgrp - attempt to set process group |
| 2595 | * @tty: tty passed by user |
| 2596 | * @real_tty: tty side device matching tty passed by user |
| 2597 | * @p: pid pointer |
| 2598 | * |
| 2599 | * Set the process group of the tty to the session passed. Only |
| 2600 | * permitted where the tty session is our session. |
| 2601 | * |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2602 | * Locking: RCU, ctrl lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2603 | */ |
| 2604 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2605 | static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2606 | { |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2607 | struct pid *pgrp; |
| 2608 | pid_t pgrp_nr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2609 | int retval = tty_check_change(real_tty); |
| 2610 | |
| 2611 | if (retval == -EIO) |
| 2612 | return -ENOTTY; |
| 2613 | if (retval) |
| 2614 | return retval; |
| 2615 | if (!current->signal->tty || |
| 2616 | (current->signal->tty != real_tty) || |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2617 | (real_tty->session != task_session(current))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2618 | return -ENOTTY; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2619 | if (get_user(pgrp_nr, p)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2620 | return -EFAULT; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2621 | if (pgrp_nr < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2622 | return -EINVAL; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2623 | rcu_read_lock(); |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 2624 | pgrp = find_vpid(pgrp_nr); |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2625 | retval = -ESRCH; |
| 2626 | if (!pgrp) |
| 2627 | goto out_unlock; |
| 2628 | retval = -EPERM; |
| 2629 | if (session_of_pgrp(pgrp) != task_session(current)) |
| 2630 | goto out_unlock; |
| 2631 | retval = 0; |
Peter Hurley | 1e86b5b | 2015-10-10 20:28:43 -0400 | [diff] [blame] | 2632 | spin_lock_irq(&tty->ctrl_lock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2633 | put_pid(real_tty->pgrp); |
| 2634 | real_tty->pgrp = get_pid(pgrp); |
Peter Hurley | 1e86b5b | 2015-10-10 20:28:43 -0400 | [diff] [blame] | 2635 | spin_unlock_irq(&tty->ctrl_lock); |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2636 | out_unlock: |
| 2637 | rcu_read_unlock(); |
| 2638 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2639 | } |
| 2640 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2641 | /** |
| 2642 | * tiocgsid - get session id |
| 2643 | * @tty: tty passed by user |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2644 | * @real_tty: tty side of the tty passed by the user if a pty else the tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2645 | * @p: pointer to returned session id |
| 2646 | * |
| 2647 | * Obtain the session id of the tty. If there is no session |
| 2648 | * return an error. |
| 2649 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2650 | * Locking: none. Reference to current->signal->tty is safe. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2651 | */ |
| 2652 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2653 | static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2654 | { |
| 2655 | /* |
| 2656 | * (tty == real_tty) is a cheap way of |
| 2657 | * testing if the tty is NOT a master pty. |
| 2658 | */ |
| 2659 | if (tty == real_tty && current->signal->tty != real_tty) |
| 2660 | return -ENOTTY; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2661 | if (!real_tty->session) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2662 | return -ENOTTY; |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 2663 | return put_user(pid_vnr(real_tty->session), p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2664 | } |
| 2665 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2666 | /** |
| 2667 | * tiocsetd - set line discipline |
| 2668 | * @tty: tty device |
| 2669 | * @p: pointer to user data |
| 2670 | * |
| 2671 | * Set the line discipline according to user request. |
| 2672 | * |
| 2673 | * Locking: see tty_set_ldisc, this function is just a helper |
| 2674 | */ |
| 2675 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2676 | static int tiocsetd(struct tty_struct *tty, int __user *p) |
| 2677 | { |
Peter Hurley | c12da96 | 2016-01-10 22:41:04 -0800 | [diff] [blame] | 2678 | int disc; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2679 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2680 | |
Peter Hurley | c12da96 | 2016-01-10 22:41:04 -0800 | [diff] [blame] | 2681 | if (get_user(disc, p)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2682 | return -EFAULT; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2683 | |
Peter Hurley | c12da96 | 2016-01-10 22:41:04 -0800 | [diff] [blame] | 2684 | ret = tty_set_ldisc(tty, disc); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2685 | |
| 2686 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2687 | } |
| 2688 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2689 | /** |
Peter Hurley | 5c17c86 | 2016-01-10 22:40:55 -0800 | [diff] [blame] | 2690 | * tiocgetd - get line discipline |
| 2691 | * @tty: tty device |
| 2692 | * @p: pointer to user data |
| 2693 | * |
| 2694 | * Retrieves the line discipline id directly from the ldisc. |
| 2695 | * |
| 2696 | * Locking: waits for ldisc reference (in case the line discipline |
| 2697 | * is changing or the tty is being hungup) |
| 2698 | */ |
| 2699 | |
| 2700 | static int tiocgetd(struct tty_struct *tty, int __user *p) |
| 2701 | { |
| 2702 | struct tty_ldisc *ld; |
| 2703 | int ret; |
| 2704 | |
| 2705 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 2706 | if (!ld) |
| 2707 | return -EIO; |
Peter Hurley | 5c17c86 | 2016-01-10 22:40:55 -0800 | [diff] [blame] | 2708 | ret = put_user(ld->ops->num, p); |
| 2709 | tty_ldisc_deref(ld); |
| 2710 | return ret; |
| 2711 | } |
| 2712 | |
| 2713 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2714 | * send_break - performed time break |
| 2715 | * @tty: device to break on |
| 2716 | * @duration: timeout in mS |
| 2717 | * |
| 2718 | * Perform a timed break on hardware that lacks its own driver level |
| 2719 | * timed break functionality. |
| 2720 | * |
| 2721 | * Locking: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2722 | * atomic_write_lock serializes |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2723 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2724 | */ |
| 2725 | |
Domen Puncer | b20f3ae | 2005-06-25 14:58:42 -0700 | [diff] [blame] | 2726 | static int send_break(struct tty_struct *tty, unsigned int duration) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2727 | { |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2728 | int retval; |
| 2729 | |
| 2730 | if (tty->ops->break_ctl == NULL) |
| 2731 | return 0; |
| 2732 | |
| 2733 | if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) |
| 2734 | retval = tty->ops->break_ctl(tty, duration); |
| 2735 | else { |
| 2736 | /* Do the work ourselves */ |
| 2737 | if (tty_write_lock(tty, 0) < 0) |
| 2738 | return -EINTR; |
| 2739 | retval = tty->ops->break_ctl(tty, -1); |
| 2740 | if (retval) |
| 2741 | goto out; |
| 2742 | if (!signal_pending(current)) |
| 2743 | msleep_interruptible(duration); |
| 2744 | retval = tty->ops->break_ctl(tty, 0); |
| 2745 | out: |
| 2746 | tty_write_unlock(tty); |
| 2747 | if (signal_pending(current)) |
| 2748 | retval = -EINTR; |
| 2749 | } |
| 2750 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2751 | } |
| 2752 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2753 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2754 | * tty_tiocmget - get modem status |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2755 | * @tty: tty device |
| 2756 | * @file: user file pointer |
| 2757 | * @p: pointer to result |
| 2758 | * |
| 2759 | * Obtain the modem status bits from the tty driver if the feature |
| 2760 | * is supported. Return -EINVAL if it is not available. |
| 2761 | * |
| 2762 | * Locking: none (up to the driver) |
| 2763 | */ |
| 2764 | |
Alan Cox | 60b33c1 | 2011-02-14 16:26:14 +0000 | [diff] [blame] | 2765 | static int tty_tiocmget(struct tty_struct *tty, int __user *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2766 | { |
| 2767 | int retval = -EINVAL; |
| 2768 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2769 | if (tty->ops->tiocmget) { |
Alan Cox | 60b33c1 | 2011-02-14 16:26:14 +0000 | [diff] [blame] | 2770 | retval = tty->ops->tiocmget(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2771 | |
| 2772 | if (retval >= 0) |
| 2773 | retval = put_user(retval, p); |
| 2774 | } |
| 2775 | return retval; |
| 2776 | } |
| 2777 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2778 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2779 | * tty_tiocmset - set modem status |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2780 | * @tty: tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2781 | * @cmd: command - clear bits, set bits or set all |
| 2782 | * @p: pointer to desired bits |
| 2783 | * |
| 2784 | * Set the modem status bits from the tty driver if the feature |
| 2785 | * is supported. Return -EINVAL if it is not available. |
| 2786 | * |
| 2787 | * Locking: none (up to the driver) |
| 2788 | */ |
| 2789 | |
Alan Cox | 20b9d17 | 2011-02-14 16:26:50 +0000 | [diff] [blame] | 2790 | static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2791 | unsigned __user *p) |
| 2792 | { |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2793 | int retval; |
| 2794 | unsigned int set, clear, val; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2795 | |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2796 | if (tty->ops->tiocmset == NULL) |
| 2797 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2798 | |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2799 | retval = get_user(val, p); |
| 2800 | if (retval) |
| 2801 | return retval; |
| 2802 | set = clear = 0; |
| 2803 | switch (cmd) { |
| 2804 | case TIOCMBIS: |
| 2805 | set = val; |
| 2806 | break; |
| 2807 | case TIOCMBIC: |
| 2808 | clear = val; |
| 2809 | break; |
| 2810 | case TIOCMSET: |
| 2811 | set = val; |
| 2812 | clear = ~val; |
| 2813 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2814 | } |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2815 | set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; |
| 2816 | clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; |
Alan Cox | 20b9d17 | 2011-02-14 16:26:50 +0000 | [diff] [blame] | 2817 | return tty->ops->tiocmset(tty, set, clear); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2818 | } |
| 2819 | |
Alan Cox | d281da7 | 2010-09-16 18:21:24 +0100 | [diff] [blame] | 2820 | static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) |
| 2821 | { |
| 2822 | int retval = -EINVAL; |
| 2823 | struct serial_icounter_struct icount; |
| 2824 | memset(&icount, 0, sizeof(icount)); |
| 2825 | if (tty->ops->get_icount) |
| 2826 | retval = tty->ops->get_icount(tty, &icount); |
| 2827 | if (retval != 0) |
| 2828 | return retval; |
| 2829 | if (copy_to_user(arg, &icount, sizeof(icount))) |
| 2830 | return -EFAULT; |
| 2831 | return 0; |
| 2832 | } |
| 2833 | |
Jiri Slaby | 8a8ae62 | 2014-11-06 16:56:33 +0100 | [diff] [blame] | 2834 | static void tty_warn_deprecated_flags(struct serial_struct __user *ss) |
| 2835 | { |
| 2836 | static DEFINE_RATELIMIT_STATE(depr_flags, |
| 2837 | DEFAULT_RATELIMIT_INTERVAL, |
| 2838 | DEFAULT_RATELIMIT_BURST); |
| 2839 | char comm[TASK_COMM_LEN]; |
| 2840 | int flags; |
| 2841 | |
| 2842 | if (get_user(flags, &ss->flags)) |
| 2843 | return; |
| 2844 | |
| 2845 | flags &= ASYNC_DEPRECATED; |
| 2846 | |
| 2847 | if (flags && __ratelimit(&depr_flags)) |
| 2848 | pr_warning("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", |
| 2849 | __func__, get_task_comm(comm, current), flags); |
| 2850 | } |
| 2851 | |
Peter Hurley | 8f166e0 | 2014-10-16 14:59:41 -0400 | [diff] [blame] | 2852 | /* |
| 2853 | * if pty, return the slave side (real_tty) |
| 2854 | * otherwise, return self |
| 2855 | */ |
| 2856 | static struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2857 | { |
| 2858 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 2859 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 2860 | tty = tty->link; |
| 2861 | return tty; |
| 2862 | } |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2863 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2864 | /* |
| 2865 | * Split this up, as gcc can choke on it otherwise.. |
| 2866 | */ |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2867 | long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2868 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2869 | struct tty_struct *tty = file_tty(file); |
| 2870 | struct tty_struct *real_tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2871 | void __user *p = (void __user *)arg; |
| 2872 | int retval; |
| 2873 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2874 | |
Al Viro | 6131ffa | 2013-02-27 16:59:05 -0500 | [diff] [blame] | 2875 | if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2876 | return -EINVAL; |
| 2877 | |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2878 | real_tty = tty_pair_get_tty(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2879 | |
| 2880 | /* |
| 2881 | * Factor out some common prep work |
| 2882 | */ |
| 2883 | switch (cmd) { |
| 2884 | case TIOCSETD: |
| 2885 | case TIOCSBRK: |
| 2886 | case TIOCCBRK: |
| 2887 | case TCSBRK: |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2888 | case TCSBRKP: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2889 | retval = tty_check_change(tty); |
| 2890 | if (retval) |
| 2891 | return retval; |
| 2892 | if (cmd != TIOCCBRK) { |
| 2893 | tty_wait_until_sent(tty, 0); |
| 2894 | if (signal_pending(current)) |
| 2895 | return -EINTR; |
| 2896 | } |
| 2897 | break; |
| 2898 | } |
| 2899 | |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2900 | /* |
| 2901 | * Now do the stuff. |
| 2902 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2903 | switch (cmd) { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2904 | case TIOCSTI: |
| 2905 | return tiocsti(tty, p); |
| 2906 | case TIOCGWINSZ: |
Alan Cox | 8f52002 | 2008-10-13 10:38:46 +0100 | [diff] [blame] | 2907 | return tiocgwinsz(real_tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2908 | case TIOCSWINSZ: |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2909 | return tiocswinsz(real_tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2910 | case TIOCCONS: |
| 2911 | return real_tty != tty ? -EINVAL : tioccons(file); |
| 2912 | case FIONBIO: |
| 2913 | return fionbio(file, p); |
| 2914 | case TIOCEXCL: |
| 2915 | set_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2916 | return 0; |
| 2917 | case TIOCNXCL: |
| 2918 | clear_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2919 | return 0; |
Cyrill Gorcunov | 84fd7bd | 2012-10-24 23:43:22 +0400 | [diff] [blame] | 2920 | case TIOCGEXCL: |
| 2921 | { |
| 2922 | int excl = test_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2923 | return put_user(excl, (int __user *)p); |
| 2924 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2925 | case TIOCNOTTY: |
| 2926 | if (current->signal->tty != tty) |
| 2927 | return -ENOTTY; |
| 2928 | no_tty(); |
| 2929 | return 0; |
| 2930 | case TIOCSCTTY: |
Peter Hurley | d1d3a0f | 2015-11-08 09:06:05 -0500 | [diff] [blame] | 2931 | return tiocsctty(real_tty, file, arg); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2932 | case TIOCGPGRP: |
| 2933 | return tiocgpgrp(tty, real_tty, p); |
| 2934 | case TIOCSPGRP: |
| 2935 | return tiocspgrp(tty, real_tty, p); |
| 2936 | case TIOCGSID: |
| 2937 | return tiocgsid(tty, real_tty, p); |
| 2938 | case TIOCGETD: |
Peter Hurley | 5c17c86 | 2016-01-10 22:40:55 -0800 | [diff] [blame] | 2939 | return tiocgetd(tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2940 | case TIOCSETD: |
| 2941 | return tiocsetd(tty, p); |
Kay Sievers | 3c95c98 | 2011-02-17 18:39:28 +0100 | [diff] [blame] | 2942 | case TIOCVHANGUP: |
| 2943 | if (!capable(CAP_SYS_ADMIN)) |
| 2944 | return -EPERM; |
| 2945 | tty_vhangup(tty); |
| 2946 | return 0; |
Werner Fink | b7b8de0 | 2010-12-03 12:48:23 +0100 | [diff] [blame] | 2947 | case TIOCGDEV: |
| 2948 | { |
| 2949 | unsigned int ret = new_encode_dev(tty_devnum(real_tty)); |
| 2950 | return put_user(ret, (unsigned int __user *)p); |
| 2951 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2952 | /* |
| 2953 | * Break handling |
| 2954 | */ |
| 2955 | case TIOCSBRK: /* Turn break on, unconditionally */ |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2956 | if (tty->ops->break_ctl) |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2957 | return tty->ops->break_ctl(tty, -1); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2958 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2959 | case TIOCCBRK: /* Turn break off, unconditionally */ |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2960 | if (tty->ops->break_ctl) |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2961 | return tty->ops->break_ctl(tty, 0); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2962 | return 0; |
| 2963 | case TCSBRK: /* SVID version: non-zero arg --> no break */ |
| 2964 | /* non-zero arg means wait for all output data |
| 2965 | * to be sent (performed above) but don't send break. |
| 2966 | * This is used by the tcdrain() termios function. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2967 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2968 | if (!arg) |
| 2969 | return send_break(tty, 250); |
| 2970 | return 0; |
| 2971 | case TCSBRKP: /* support for POSIX tcsendbreak() */ |
| 2972 | return send_break(tty, arg ? arg*100 : 250); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2973 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2974 | case TIOCMGET: |
Alan Cox | 60b33c1 | 2011-02-14 16:26:14 +0000 | [diff] [blame] | 2975 | return tty_tiocmget(tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2976 | case TIOCMSET: |
| 2977 | case TIOCMBIC: |
| 2978 | case TIOCMBIS: |
Alan Cox | 20b9d17 | 2011-02-14 16:26:50 +0000 | [diff] [blame] | 2979 | return tty_tiocmset(tty, cmd, p); |
Alan Cox | d281da7 | 2010-09-16 18:21:24 +0100 | [diff] [blame] | 2980 | case TIOCGICOUNT: |
| 2981 | retval = tty_tiocgicount(tty, p); |
| 2982 | /* For the moment allow fall through to the old method */ |
| 2983 | if (retval != -EINVAL) |
| 2984 | return retval; |
| 2985 | break; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2986 | case TCFLSH: |
| 2987 | switch (arg) { |
| 2988 | case TCIFLUSH: |
| 2989 | case TCIOFLUSH: |
| 2990 | /* flush tty buffer and allow ldisc to process ioctl */ |
Peter Hurley | 86c80a8 | 2014-11-05 12:13:09 -0500 | [diff] [blame] | 2991 | tty_buffer_flush(tty, NULL); |
Paul Fulghum | c5c34d4 | 2007-05-12 10:36:55 -0700 | [diff] [blame] | 2992 | break; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2993 | } |
| 2994 | break; |
Jiri Slaby | 8a8ae62 | 2014-11-06 16:56:33 +0100 | [diff] [blame] | 2995 | case TIOCSSERIAL: |
| 2996 | tty_warn_deprecated_flags(p); |
| 2997 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2998 | } |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2999 | if (tty->ops->ioctl) { |
Peter Hurley | c961bfb | 2014-11-05 12:26:25 -0500 | [diff] [blame] | 3000 | retval = tty->ops->ioctl(tty, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3001 | if (retval != -ENOIOCTLCMD) |
| 3002 | return retval; |
| 3003 | } |
| 3004 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 3005 | if (!ld) |
| 3006 | return hung_up_tty_ioctl(file, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3007 | retval = -EINVAL; |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 3008 | if (ld->ops->ioctl) { |
| 3009 | retval = ld->ops->ioctl(tty, file, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3010 | if (retval == -ENOIOCTLCMD) |
Wanlong Gao | bbb63c5 | 2012-08-27 15:23:12 +0800 | [diff] [blame] | 3011 | retval = -ENOTTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3012 | } |
| 3013 | tty_ldisc_deref(ld); |
| 3014 | return retval; |
| 3015 | } |
| 3016 | |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 3017 | #ifdef CONFIG_COMPAT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3018 | static long tty_compat_ioctl(struct file *file, unsigned int cmd, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 3019 | unsigned long arg) |
| 3020 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 3021 | struct tty_struct *tty = file_tty(file); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 3022 | struct tty_ldisc *ld; |
| 3023 | int retval = -ENOIOCTLCMD; |
| 3024 | |
Al Viro | 6131ffa | 2013-02-27 16:59:05 -0500 | [diff] [blame] | 3025 | if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl")) |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 3026 | return -EINVAL; |
| 3027 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3028 | if (tty->ops->compat_ioctl) { |
Peter Hurley | c961bfb | 2014-11-05 12:26:25 -0500 | [diff] [blame] | 3029 | retval = tty->ops->compat_ioctl(tty, cmd, arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 3030 | if (retval != -ENOIOCTLCMD) |
| 3031 | return retval; |
| 3032 | } |
| 3033 | |
| 3034 | ld = tty_ldisc_ref_wait(tty); |
Peter Hurley | e55afd1 | 2016-01-10 22:41:01 -0800 | [diff] [blame] | 3035 | if (!ld) |
| 3036 | return hung_up_tty_compat_ioctl(file, cmd, arg); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 3037 | if (ld->ops->compat_ioctl) |
| 3038 | retval = ld->ops->compat_ioctl(tty, file, cmd, arg); |
Thomas Meyer | 8193c42 | 2011-10-05 23:13:13 +0200 | [diff] [blame] | 3039 | else |
| 3040 | retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 3041 | tty_ldisc_deref(ld); |
| 3042 | |
| 3043 | return retval; |
| 3044 | } |
| 3045 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3046 | |
Al Viro | c3c073f | 2012-08-21 22:32:06 -0400 | [diff] [blame] | 3047 | static int this_tty(const void *t, struct file *file, unsigned fd) |
| 3048 | { |
| 3049 | if (likely(file->f_op->read != tty_read)) |
| 3050 | return 0; |
| 3051 | return file_tty(file) != t ? 0 : fd + 1; |
| 3052 | } |
| 3053 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3054 | /* |
| 3055 | * This implements the "Secure Attention Key" --- the idea is to |
| 3056 | * prevent trojan horses by killing all processes associated with this |
| 3057 | * tty when the user hits the "Secure Attention Key". Required for |
| 3058 | * super-paranoid applications --- see the Orange Book for more details. |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3059 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3060 | * This code could be nicer; ideally it should send a HUP, wait a few |
| 3061 | * seconds, then send a INT, and then a KILL signal. But you then |
| 3062 | * have to coordinate with the init process, since all processes associated |
| 3063 | * with the current tty must be dead before the new getty is allowed |
| 3064 | * to spawn. |
| 3065 | * |
| 3066 | * Now, if it would be correct ;-/ The current code has a nasty hole - |
| 3067 | * it doesn't catch files in flight. We may send the descriptor to ourselves |
| 3068 | * via AF_UNIX socket, close it and later fetch from socket. FIXME. |
| 3069 | * |
| 3070 | * Nasty bug: do_SAK is being called in interrupt context. This can |
| 3071 | * deadlock. We punt it up to process context. AKPM - 16Mar2001 |
| 3072 | */ |
Eric W. Biederman | 8b6312f | 2007-02-10 01:44:34 -0800 | [diff] [blame] | 3073 | void __do_SAK(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3074 | { |
| 3075 | #ifdef TTY_SOFT_SAK |
| 3076 | tty_hangup(tty); |
| 3077 | #else |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 3078 | struct task_struct *g, *p; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3079 | struct pid *session; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3080 | int i; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3081 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3082 | if (!tty) |
| 3083 | return; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3084 | session = tty->session; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3085 | |
Dan Carpenter | b3f13de | 2006-12-13 00:35:09 -0800 | [diff] [blame] | 3086 | tty_ldisc_flush(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3087 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3088 | tty_driver_flush_buffer(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3089 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3090 | read_lock(&tasklist_lock); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 3091 | /* Kill the entire session */ |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3092 | do_each_pid_task(session, PIDTYPE_SID, p) { |
Peter Hurley | 9b42bb7 | 2015-11-08 13:01:14 -0500 | [diff] [blame] | 3093 | tty_notice(tty, "SAK: killed process %d (%s): by session\n", |
| 3094 | task_pid_nr(p), p->comm); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 3095 | send_sig(SIGKILL, p, 1); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3096 | } while_each_pid_task(session, PIDTYPE_SID, p); |
Peter Hurley | 9b42bb7 | 2015-11-08 13:01:14 -0500 | [diff] [blame] | 3097 | |
| 3098 | /* Now kill any processes that happen to have the tty open */ |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 3099 | do_each_thread(g, p) { |
| 3100 | if (p->signal->tty == tty) { |
Peter Hurley | 9b42bb7 | 2015-11-08 13:01:14 -0500 | [diff] [blame] | 3101 | tty_notice(tty, "SAK: killed process %d (%s): by controlling tty\n", |
| 3102 | task_pid_nr(p), p->comm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3103 | send_sig(SIGKILL, p, 1); |
| 3104 | continue; |
| 3105 | } |
| 3106 | task_lock(p); |
Al Viro | c3c073f | 2012-08-21 22:32:06 -0400 | [diff] [blame] | 3107 | i = iterate_fd(p->files, 0, this_tty, tty); |
| 3108 | if (i != 0) { |
Peter Hurley | 9b42bb7 | 2015-11-08 13:01:14 -0500 | [diff] [blame] | 3109 | tty_notice(tty, "SAK: killed process %d (%s): by fd#%d\n", |
| 3110 | task_pid_nr(p), p->comm, i - 1); |
Al Viro | c3c073f | 2012-08-21 22:32:06 -0400 | [diff] [blame] | 3111 | force_sig(SIGKILL, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3112 | } |
| 3113 | task_unlock(p); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 3114 | } while_each_thread(g, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3115 | read_unlock(&tasklist_lock); |
| 3116 | #endif |
| 3117 | } |
| 3118 | |
Eric W. Biederman | 8b6312f | 2007-02-10 01:44:34 -0800 | [diff] [blame] | 3119 | static void do_SAK_work(struct work_struct *work) |
| 3120 | { |
| 3121 | struct tty_struct *tty = |
| 3122 | container_of(work, struct tty_struct, SAK_work); |
| 3123 | __do_SAK(tty); |
| 3124 | } |
| 3125 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3126 | /* |
| 3127 | * The tq handling here is a little racy - tty->SAK_work may already be queued. |
| 3128 | * Fortunately we don't need to worry, because if ->SAK_work is already queued, |
| 3129 | * the values which we write to it will be identical to the values which it |
| 3130 | * already has. --akpm |
| 3131 | */ |
| 3132 | void do_SAK(struct tty_struct *tty) |
| 3133 | { |
| 3134 | if (!tty) |
| 3135 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3136 | schedule_work(&tty->SAK_work); |
| 3137 | } |
| 3138 | |
| 3139 | EXPORT_SYMBOL(do_SAK); |
| 3140 | |
Greg Kroah-Hartman | 6e9430a | 2013-02-06 15:59:18 -0800 | [diff] [blame] | 3141 | static int dev_match_devt(struct device *dev, const void *data) |
Dmitry Eremin-Solenikov | 30004ac | 2010-08-09 18:22:49 +0400 | [diff] [blame] | 3142 | { |
Greg Kroah-Hartman | 6e9430a | 2013-02-06 15:59:18 -0800 | [diff] [blame] | 3143 | const dev_t *devt = data; |
Dmitry Eremin-Solenikov | 30004ac | 2010-08-09 18:22:49 +0400 | [diff] [blame] | 3144 | return dev->devt == *devt; |
| 3145 | } |
| 3146 | |
| 3147 | /* Must put_device() after it's unused! */ |
| 3148 | static struct device *tty_get_device(struct tty_struct *tty) |
| 3149 | { |
| 3150 | dev_t devt = tty_devnum(tty); |
| 3151 | return class_find_device(tty_class, NULL, &devt, dev_match_devt); |
| 3152 | } |
| 3153 | |
| 3154 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3155 | /** |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 3156 | * alloc_tty_struct |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3157 | * |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 3158 | * This subroutine allocates and initializes a tty structure. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3159 | * |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 3160 | * Locking: none - tty in question is not exposed at this point |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3161 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3162 | |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 3163 | struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3164 | { |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 3165 | struct tty_struct *tty; |
| 3166 | |
| 3167 | tty = kzalloc(sizeof(*tty), GFP_KERNEL); |
| 3168 | if (!tty) |
| 3169 | return NULL; |
| 3170 | |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3171 | kref_init(&tty->kref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3172 | tty->magic = TTY_MAGIC; |
Tetsuo Handa | 6a506d4 | 2018-04-05 19:40:16 +0900 | [diff] [blame] | 3173 | if (tty_ldisc_init(tty)) { |
| 3174 | kfree(tty); |
| 3175 | return NULL; |
| 3176 | } |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3177 | tty->session = NULL; |
| 3178 | tty->pgrp = NULL; |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 3179 | mutex_init(&tty->legacy_mutex); |
Peter Hurley | d8c1f92 | 2013-06-15 09:14:31 -0400 | [diff] [blame] | 3180 | mutex_init(&tty->throttle_mutex); |
Peter Hurley | 6a1c068 | 2013-06-15 09:14:23 -0400 | [diff] [blame] | 3181 | init_rwsem(&tty->termios_rwsem); |
Peter Hurley | dee4a0b | 2013-07-24 16:43:51 -0400 | [diff] [blame] | 3182 | mutex_init(&tty->winsize_mutex); |
Peter Hurley | 3669752 | 2013-06-15 07:04:48 -0400 | [diff] [blame] | 3183 | init_ldsem(&tty->ldisc_sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3184 | init_waitqueue_head(&tty->write_wait); |
| 3185 | init_waitqueue_head(&tty->read_wait); |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 3186 | INIT_WORK(&tty->hangup_work, do_tty_hangup); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 3187 | mutex_init(&tty->atomic_write_lock); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 3188 | spin_lock_init(&tty->ctrl_lock); |
Peter Hurley | f9e053d | 2014-09-10 15:06:31 -0400 | [diff] [blame] | 3189 | spin_lock_init(&tty->flow_lock); |
Peter Hurley | 4a51096 | 2016-01-09 21:35:23 -0800 | [diff] [blame] | 3190 | spin_lock_init(&tty->files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3191 | INIT_LIST_HEAD(&tty->tty_files); |
Eric W. Biederman | 7f1f86a | 2007-02-13 14:38:58 -0700 | [diff] [blame] | 3192 | INIT_WORK(&tty->SAK_work, do_SAK_work); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 3193 | |
| 3194 | tty->driver = driver; |
| 3195 | tty->ops = driver->ops; |
| 3196 | tty->index = idx; |
| 3197 | tty_line_name(driver, idx, tty->name); |
Dmitry Eremin-Solenikov | 30004ac | 2010-08-09 18:22:49 +0400 | [diff] [blame] | 3198 | tty->dev = tty_get_device(tty); |
Rasmus Villemoes | 2c964a2 | 2014-07-10 21:01:22 +0200 | [diff] [blame] | 3199 | |
| 3200 | return tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3201 | } |
| 3202 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3203 | /** |
| 3204 | * tty_put_char - write one character to a tty |
| 3205 | * @tty: tty |
| 3206 | * @ch: character |
| 3207 | * |
| 3208 | * Write one byte to the tty using the provided put_char method |
| 3209 | * if present. Returns the number of characters successfully output. |
| 3210 | * |
| 3211 | * Note: the specific put_char operation in the driver layer may go |
| 3212 | * away soon. Don't call it directly, use this method |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3213 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3214 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3215 | int tty_put_char(struct tty_struct *tty, unsigned char ch) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3216 | { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3217 | if (tty->ops->put_char) |
| 3218 | return tty->ops->put_char(tty, ch); |
| 3219 | return tty->ops->write(tty, &ch, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3220 | } |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3221 | EXPORT_SYMBOL_GPL(tty_put_char); |
| 3222 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3223 | struct class *tty_class; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3224 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3225 | static int tty_cdev_add(struct tty_driver *driver, dev_t dev, |
| 3226 | unsigned int index, unsigned int count) |
| 3227 | { |
Leon Yu | c1a752b | 2015-09-07 13:08:37 +0000 | [diff] [blame] | 3228 | int err; |
| 3229 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3230 | /* init here, since reused cdevs cause crashes */ |
Richard Watts | a3a10ce | 2015-05-19 16:06:53 +0100 | [diff] [blame] | 3231 | driver->cdevs[index] = cdev_alloc(); |
| 3232 | if (!driver->cdevs[index]) |
| 3233 | return -ENOMEM; |
Leon Yu | c1a752b | 2015-09-07 13:08:37 +0000 | [diff] [blame] | 3234 | driver->cdevs[index]->ops = &tty_fops; |
Richard Watts | a3a10ce | 2015-05-19 16:06:53 +0100 | [diff] [blame] | 3235 | driver->cdevs[index]->owner = driver->owner; |
Leon Yu | c1a752b | 2015-09-07 13:08:37 +0000 | [diff] [blame] | 3236 | err = cdev_add(driver->cdevs[index], dev, count); |
| 3237 | if (err) |
| 3238 | kobject_put(&driver->cdevs[index]->kobj); |
| 3239 | return err; |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3240 | } |
| 3241 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3242 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3243 | * tty_register_device - register a tty device |
| 3244 | * @driver: the tty driver that describes the tty device |
| 3245 | * @index: the index in the tty driver for this tty device |
| 3246 | * @device: a struct device that is associated with this tty device. |
| 3247 | * This field is optional, if there is no known struct device |
| 3248 | * for this tty device it can be set to NULL safely. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3249 | * |
Greg Kroah-Hartman | 01107d3 | 2006-08-07 22:19:37 -0700 | [diff] [blame] | 3250 | * Returns a pointer to the struct device for this tty device |
| 3251 | * (or ERR_PTR(-EFOO) on error). |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 3252 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3253 | * This call is required to be made to register an individual tty device |
| 3254 | * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If |
| 3255 | * that bit is not set, this function should not be called by a tty |
| 3256 | * driver. |
| 3257 | * |
| 3258 | * Locking: ?? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3259 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3260 | |
Greg Kroah-Hartman | 01107d3 | 2006-08-07 22:19:37 -0700 | [diff] [blame] | 3261 | struct device *tty_register_device(struct tty_driver *driver, unsigned index, |
| 3262 | struct device *device) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3263 | { |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3264 | return tty_register_device_attr(driver, index, device, NULL, NULL); |
| 3265 | } |
| 3266 | EXPORT_SYMBOL(tty_register_device); |
| 3267 | |
Tomas Hlavacek | b1b7991 | 2012-09-06 23:17:47 +0200 | [diff] [blame] | 3268 | static void tty_device_create_release(struct device *dev) |
| 3269 | { |
Peter Hurley | 83db1df | 2015-11-08 13:01:21 -0500 | [diff] [blame] | 3270 | dev_dbg(dev, "releasing...\n"); |
Tomas Hlavacek | b1b7991 | 2012-09-06 23:17:47 +0200 | [diff] [blame] | 3271 | kfree(dev); |
| 3272 | } |
| 3273 | |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3274 | /** |
| 3275 | * tty_register_device_attr - register a tty device |
| 3276 | * @driver: the tty driver that describes the tty device |
| 3277 | * @index: the index in the tty driver for this tty device |
| 3278 | * @device: a struct device that is associated with this tty device. |
| 3279 | * This field is optional, if there is no known struct device |
| 3280 | * for this tty device it can be set to NULL safely. |
| 3281 | * @drvdata: Driver data to be set to device. |
| 3282 | * @attr_grp: Attribute group to be set on device. |
| 3283 | * |
| 3284 | * Returns a pointer to the struct device for this tty device |
| 3285 | * (or ERR_PTR(-EFOO) on error). |
| 3286 | * |
| 3287 | * This call is required to be made to register an individual tty device |
| 3288 | * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If |
| 3289 | * that bit is not set, this function should not be called by a tty |
| 3290 | * driver. |
| 3291 | * |
| 3292 | * Locking: ?? |
| 3293 | */ |
| 3294 | struct device *tty_register_device_attr(struct tty_driver *driver, |
| 3295 | unsigned index, struct device *device, |
| 3296 | void *drvdata, |
| 3297 | const struct attribute_group **attr_grp) |
| 3298 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3299 | char name[64]; |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3300 | dev_t devt = MKDEV(driver->major, driver->minor_start) + index; |
| 3301 | struct device *dev = NULL; |
| 3302 | int retval = -ENODEV; |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3303 | bool cdev = false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3304 | |
| 3305 | if (index >= driver->num) { |
Peter Hurley | 656fb86 | 2015-11-08 13:01:15 -0500 | [diff] [blame] | 3306 | pr_err("%s: Attempt to register invalid tty line number (%d)\n", |
| 3307 | driver->name, index); |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 3308 | return ERR_PTR(-EINVAL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3309 | } |
| 3310 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3311 | if (driver->type == TTY_DRIVER_TYPE_PTY) |
| 3312 | pty_line_name(driver, index, name); |
| 3313 | else |
| 3314 | tty_line_name(driver, index, name); |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 3315 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3316 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3317 | retval = tty_cdev_add(driver, devt, index, 1); |
| 3318 | if (retval) |
| 3319 | goto error; |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3320 | cdev = true; |
| 3321 | } |
| 3322 | |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3323 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
| 3324 | if (!dev) { |
| 3325 | retval = -ENOMEM; |
| 3326 | goto error; |
| 3327 | } |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3328 | |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3329 | dev->devt = devt; |
| 3330 | dev->class = tty_class; |
| 3331 | dev->parent = device; |
Tomas Hlavacek | b1b7991 | 2012-09-06 23:17:47 +0200 | [diff] [blame] | 3332 | dev->release = tty_device_create_release; |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3333 | dev_set_name(dev, "%s", name); |
| 3334 | dev->groups = attr_grp; |
| 3335 | dev_set_drvdata(dev, drvdata); |
| 3336 | |
| 3337 | retval = device_register(dev); |
| 3338 | if (retval) |
| 3339 | goto error; |
| 3340 | |
| 3341 | return dev; |
| 3342 | |
| 3343 | error: |
| 3344 | put_device(dev); |
Richard Watts | a3a10ce | 2015-05-19 16:06:53 +0100 | [diff] [blame] | 3345 | if (cdev) { |
| 3346 | cdev_del(driver->cdevs[index]); |
| 3347 | driver->cdevs[index] = NULL; |
| 3348 | } |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3349 | return ERR_PTR(retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3350 | } |
Tomas Hlavacek | 6915c0e | 2012-09-06 03:17:18 +0200 | [diff] [blame] | 3351 | EXPORT_SYMBOL_GPL(tty_register_device_attr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3352 | |
| 3353 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3354 | * tty_unregister_device - unregister a tty device |
| 3355 | * @driver: the tty driver that describes the tty device |
| 3356 | * @index: the index in the tty driver for this tty device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3357 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3358 | * If a tty device is registered with a call to tty_register_device() then |
| 3359 | * this function must be called when the tty device is gone. |
| 3360 | * |
| 3361 | * Locking: ?? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3362 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3363 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3364 | void tty_unregister_device(struct tty_driver *driver, unsigned index) |
| 3365 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3366 | device_destroy(tty_class, |
| 3367 | MKDEV(driver->major, driver->minor_start) + index); |
Richard Watts | a3a10ce | 2015-05-19 16:06:53 +0100 | [diff] [blame] | 3368 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { |
| 3369 | cdev_del(driver->cdevs[index]); |
| 3370 | driver->cdevs[index] = NULL; |
| 3371 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3372 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3373 | EXPORT_SYMBOL(tty_unregister_device); |
| 3374 | |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3375 | /** |
| 3376 | * __tty_alloc_driver -- allocate tty driver |
| 3377 | * @lines: count of lines this driver can handle at most |
| 3378 | * @owner: module which is repsonsible for this driver |
| 3379 | * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags |
| 3380 | * |
| 3381 | * This should not be called directly, some of the provided macros should be |
| 3382 | * used instead. Use IS_ERR and friends on @retval. |
| 3383 | */ |
| 3384 | struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner, |
| 3385 | unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3386 | { |
| 3387 | struct tty_driver *driver; |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3388 | unsigned int cdevs = 1; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3389 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3390 | |
Jiri Slaby | 0019b40 | 2012-08-08 22:26:43 +0200 | [diff] [blame] | 3391 | if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1)) |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3392 | return ERR_PTR(-EINVAL); |
| 3393 | |
Jean Delvare | 506eb99 | 2007-07-15 23:40:14 -0700 | [diff] [blame] | 3394 | driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3395 | if (!driver) |
| 3396 | return ERR_PTR(-ENOMEM); |
| 3397 | |
| 3398 | kref_init(&driver->kref); |
| 3399 | driver->magic = TTY_DRIVER_MAGIC; |
| 3400 | driver->num = lines; |
| 3401 | driver->owner = owner; |
| 3402 | driver->flags = flags; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3403 | |
| 3404 | if (!(flags & TTY_DRIVER_DEVPTS_MEM)) { |
| 3405 | driver->ttys = kcalloc(lines, sizeof(*driver->ttys), |
| 3406 | GFP_KERNEL); |
| 3407 | driver->termios = kcalloc(lines, sizeof(*driver->termios), |
| 3408 | GFP_KERNEL); |
| 3409 | if (!driver->ttys || !driver->termios) { |
| 3410 | err = -ENOMEM; |
| 3411 | goto err_free_all; |
| 3412 | } |
| 3413 | } |
| 3414 | |
| 3415 | if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) { |
| 3416 | driver->ports = kcalloc(lines, sizeof(*driver->ports), |
| 3417 | GFP_KERNEL); |
| 3418 | if (!driver->ports) { |
| 3419 | err = -ENOMEM; |
| 3420 | goto err_free_all; |
| 3421 | } |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3422 | cdevs = lines; |
| 3423 | } |
| 3424 | |
| 3425 | driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL); |
| 3426 | if (!driver->cdevs) { |
| 3427 | err = -ENOMEM; |
| 3428 | goto err_free_all; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3429 | } |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3430 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3431 | return driver; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3432 | err_free_all: |
| 3433 | kfree(driver->ports); |
| 3434 | kfree(driver->ttys); |
| 3435 | kfree(driver->termios); |
Richard Watts | a3a10ce | 2015-05-19 16:06:53 +0100 | [diff] [blame] | 3436 | kfree(driver->cdevs); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3437 | kfree(driver); |
| 3438 | return ERR_PTR(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3439 | } |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3440 | EXPORT_SYMBOL(__tty_alloc_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3441 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3442 | static void destruct_tty_driver(struct kref *kref) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3443 | { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3444 | struct tty_driver *driver = container_of(kref, struct tty_driver, kref); |
| 3445 | int i; |
| 3446 | struct ktermios *tp; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3447 | |
| 3448 | if (driver->flags & TTY_DRIVER_INSTALLED) { |
| 3449 | /* |
| 3450 | * Free the termios and termios_locked structures because |
| 3451 | * we don't want to get memory leaks when modular tty |
| 3452 | * drivers are removed from the kernel. |
| 3453 | */ |
| 3454 | for (i = 0; i < driver->num; i++) { |
| 3455 | tp = driver->termios[i]; |
| 3456 | if (tp) { |
| 3457 | driver->termios[i] = NULL; |
| 3458 | kfree(tp); |
| 3459 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3460 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) |
| 3461 | tty_unregister_device(driver, i); |
| 3462 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3463 | proc_tty_unregister_driver(driver); |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3464 | if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) |
Richard Watts | a3a10ce | 2015-05-19 16:06:53 +0100 | [diff] [blame] | 3465 | cdev_del(driver->cdevs[0]); |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3466 | } |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3467 | kfree(driver->cdevs); |
Jiri Slaby | 04831dc | 2012-06-04 13:35:36 +0200 | [diff] [blame] | 3468 | kfree(driver->ports); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3469 | kfree(driver->termios); |
| 3470 | kfree(driver->ttys); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3471 | kfree(driver); |
| 3472 | } |
| 3473 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3474 | void tty_driver_kref_put(struct tty_driver *driver) |
| 3475 | { |
| 3476 | kref_put(&driver->kref, destruct_tty_driver); |
| 3477 | } |
| 3478 | EXPORT_SYMBOL(tty_driver_kref_put); |
| 3479 | |
Jeff Dike | b68e31d | 2006-10-02 02:17:18 -0700 | [diff] [blame] | 3480 | void tty_set_operations(struct tty_driver *driver, |
| 3481 | const struct tty_operations *op) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3482 | { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3483 | driver->ops = op; |
| 3484 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3485 | EXPORT_SYMBOL(tty_set_operations); |
| 3486 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3487 | void put_tty_driver(struct tty_driver *d) |
| 3488 | { |
| 3489 | tty_driver_kref_put(d); |
| 3490 | } |
| 3491 | EXPORT_SYMBOL(put_tty_driver); |
| 3492 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3493 | /* |
| 3494 | * Called by a tty driver to register itself. |
| 3495 | */ |
| 3496 | int tty_register_driver(struct tty_driver *driver) |
| 3497 | { |
| 3498 | int error; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3499 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3500 | dev_t dev; |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3501 | struct device *d; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3502 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3503 | if (!driver->major) { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3504 | error = alloc_chrdev_region(&dev, driver->minor_start, |
| 3505 | driver->num, driver->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3506 | if (!error) { |
| 3507 | driver->major = MAJOR(dev); |
| 3508 | driver->minor_start = MINOR(dev); |
| 3509 | } |
| 3510 | } else { |
| 3511 | dev = MKDEV(driver->major, driver->minor_start); |
Geert Uytterhoeven | e5717c4 | 2007-02-20 15:45:21 +0100 | [diff] [blame] | 3512 | error = register_chrdev_region(dev, driver->num, driver->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3513 | } |
Jiri Slaby | 9bb8a3d | 2012-06-04 13:35:35 +0200 | [diff] [blame] | 3514 | if (error < 0) |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3515 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3516 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3517 | if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) { |
| 3518 | error = tty_cdev_add(driver, dev, 0, driver->num); |
| 3519 | if (error) |
| 3520 | goto err_unreg_char; |
| 3521 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3522 | |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3523 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3524 | list_add(&driver->tty_drivers, &tty_drivers); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3525 | mutex_unlock(&tty_mutex); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3526 | |
| 3527 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3528 | for (i = 0; i < driver->num; i++) { |
| 3529 | d = tty_register_device(driver, i, NULL); |
| 3530 | if (IS_ERR(d)) { |
| 3531 | error = PTR_ERR(d); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3532 | goto err_unreg_devs; |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3533 | } |
| 3534 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3535 | } |
| 3536 | proc_tty_register_driver(driver); |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3537 | driver->flags |= TTY_DRIVER_INSTALLED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3538 | return 0; |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3539 | |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3540 | err_unreg_devs: |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3541 | for (i--; i >= 0; i--) |
| 3542 | tty_unregister_device(driver, i); |
| 3543 | |
| 3544 | mutex_lock(&tty_mutex); |
| 3545 | list_del(&driver->tty_drivers); |
| 3546 | mutex_unlock(&tty_mutex); |
| 3547 | |
Jiri Slaby | 9bb8a3d | 2012-06-04 13:35:35 +0200 | [diff] [blame] | 3548 | err_unreg_char: |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3549 | unregister_chrdev_region(dev, driver->num); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3550 | err: |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3551 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3552 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3553 | EXPORT_SYMBOL(tty_register_driver); |
| 3554 | |
| 3555 | /* |
| 3556 | * Called by a tty driver to unregister itself. |
| 3557 | */ |
| 3558 | int tty_unregister_driver(struct tty_driver *driver) |
| 3559 | { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3560 | #if 0 |
| 3561 | /* FIXME */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3562 | if (driver->refcount) |
| 3563 | return -EBUSY; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3564 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3565 | unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), |
| 3566 | driver->num); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3567 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3568 | list_del(&driver->tty_drivers); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3569 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3570 | return 0; |
| 3571 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3572 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3573 | EXPORT_SYMBOL(tty_unregister_driver); |
| 3574 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3575 | dev_t tty_devnum(struct tty_struct *tty) |
| 3576 | { |
| 3577 | return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; |
| 3578 | } |
| 3579 | EXPORT_SYMBOL(tty_devnum); |
| 3580 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3581 | void tty_default_fops(struct file_operations *fops) |
| 3582 | { |
| 3583 | *fops = tty_fops; |
| 3584 | } |
| 3585 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3586 | /* |
| 3587 | * Initialize the console device. This is called *early*, so |
| 3588 | * we can't necessarily depend on lots of kernel help here. |
| 3589 | * Just do some early initializations, and do the complex setup |
| 3590 | * later. |
| 3591 | */ |
| 3592 | void __init console_init(void) |
| 3593 | { |
| 3594 | initcall_t *call; |
| 3595 | |
| 3596 | /* Setup the default TTY line discipline. */ |
Peter Hurley | 2722873 | 2016-01-09 21:35:19 -0800 | [diff] [blame] | 3597 | n_tty_init(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3598 | |
| 3599 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3600 | * set up the console device so that later boot sequences can |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3601 | * inform about problems etc.. |
| 3602 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3603 | call = __con_initcall_start; |
| 3604 | while (call < __con_initcall_end) { |
| 3605 | (*call)(); |
| 3606 | call++; |
| 3607 | } |
| 3608 | } |
| 3609 | |
Al Viro | 2c9ede5 | 2011-07-23 20:24:48 -0400 | [diff] [blame] | 3610 | static char *tty_devnode(struct device *dev, umode_t *mode) |
Kay Sievers | e454cea | 2009-09-18 23:01:12 +0200 | [diff] [blame] | 3611 | { |
| 3612 | if (!mode) |
| 3613 | return NULL; |
| 3614 | if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || |
| 3615 | dev->devt == MKDEV(TTYAUX_MAJOR, 2)) |
| 3616 | *mode = 0666; |
| 3617 | return NULL; |
| 3618 | } |
| 3619 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3620 | static int __init tty_class_init(void) |
| 3621 | { |
gregkh@suse.de | 7fe845d | 2005-03-15 14:23:15 -0800 | [diff] [blame] | 3622 | tty_class = class_create(THIS_MODULE, "tty"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3623 | if (IS_ERR(tty_class)) |
| 3624 | return PTR_ERR(tty_class); |
Kay Sievers | e454cea | 2009-09-18 23:01:12 +0200 | [diff] [blame] | 3625 | tty_class->devnode = tty_devnode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3626 | return 0; |
| 3627 | } |
| 3628 | |
| 3629 | postcore_initcall(tty_class_init); |
| 3630 | |
| 3631 | /* 3/2004 jmc: why do these devices exist? */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3632 | static struct cdev tty_cdev, console_cdev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3633 | |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3634 | static ssize_t show_cons_active(struct device *dev, |
| 3635 | struct device_attribute *attr, char *buf) |
| 3636 | { |
| 3637 | struct console *cs[16]; |
| 3638 | int i = 0; |
| 3639 | struct console *c; |
| 3640 | ssize_t count = 0; |
| 3641 | |
Torben Hohn | ac751ef | 2011-01-25 15:07:35 -0800 | [diff] [blame] | 3642 | console_lock(); |
Kay Sievers | a2a6a82 | 2011-01-09 16:39:14 +0100 | [diff] [blame] | 3643 | for_each_console(c) { |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3644 | if (!c->device) |
| 3645 | continue; |
| 3646 | if (!c->write) |
| 3647 | continue; |
| 3648 | if ((c->flags & CON_ENABLED) == 0) |
| 3649 | continue; |
| 3650 | cs[i++] = c; |
| 3651 | if (i >= ARRAY_SIZE(cs)) |
| 3652 | break; |
| 3653 | } |
Hannes Reinecke | 723abd8 | 2014-02-27 12:30:51 +0100 | [diff] [blame] | 3654 | while (i--) { |
| 3655 | int index = cs[i]->index; |
| 3656 | struct tty_driver *drv = cs[i]->device(cs[i], &index); |
| 3657 | |
| 3658 | /* don't resolve tty0 as some programs depend on it */ |
| 3659 | if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR)) |
| 3660 | count += tty_line_name(drv, index, buf + count); |
| 3661 | else |
| 3662 | count += sprintf(buf + count, "%s%d", |
| 3663 | cs[i]->name, cs[i]->index); |
| 3664 | |
| 3665 | count += sprintf(buf + count, "%c", i ? ' ':'\n'); |
| 3666 | } |
Torben Hohn | ac751ef | 2011-01-25 15:07:35 -0800 | [diff] [blame] | 3667 | console_unlock(); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3668 | |
| 3669 | return count; |
| 3670 | } |
| 3671 | static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL); |
| 3672 | |
Takashi Iwai | 1083a7b | 2015-02-05 11:07:42 +0100 | [diff] [blame] | 3673 | static struct attribute *cons_dev_attrs[] = { |
| 3674 | &dev_attr_active.attr, |
| 3675 | NULL |
| 3676 | }; |
| 3677 | |
| 3678 | ATTRIBUTE_GROUPS(cons_dev); |
| 3679 | |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3680 | static struct device *consdev; |
| 3681 | |
| 3682 | void console_sysfs_notify(void) |
| 3683 | { |
| 3684 | if (consdev) |
| 3685 | sysfs_notify(&consdev->kobj, NULL, "active"); |
| 3686 | } |
| 3687 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3688 | /* |
| 3689 | * Ok, now we can initialize the rest of the tty devices and can count |
| 3690 | * on memory allocations, interrupts etc.. |
| 3691 | */ |
David Howells | 31d1d48 | 2010-08-06 16:34:43 +0100 | [diff] [blame] | 3692 | int __init tty_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3693 | { |
| 3694 | cdev_init(&tty_cdev, &tty_fops); |
| 3695 | if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || |
| 3696 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) |
| 3697 | panic("Couldn't register /dev/tty driver\n"); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3698 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3699 | |
| 3700 | cdev_init(&console_cdev, &console_fops); |
| 3701 | if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || |
| 3702 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) |
| 3703 | panic("Couldn't register /dev/console driver\n"); |
Takashi Iwai | 1083a7b | 2015-02-05 11:07:42 +0100 | [diff] [blame] | 3704 | consdev = device_create_with_groups(tty_class, NULL, |
| 3705 | MKDEV(TTYAUX_MAJOR, 1), NULL, |
| 3706 | cons_dev_groups, "console"); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3707 | if (IS_ERR(consdev)) |
| 3708 | consdev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3709 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3710 | #ifdef CONFIG_VT |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3711 | vty_init(&console_fops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3712 | #endif |
| 3713 | return 0; |
| 3714 | } |
David Howells | 31d1d48 | 2010-08-06 16:34:43 +0100 | [diff] [blame] | 3715 | |