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 |
| 109 | |
| 110 | #define TTY_PARANOIA_CHECK 1 |
| 111 | #define CHECK_TTY_COUNT 1 |
| 112 | |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 113 | struct ktermios tty_std_termios = { /* for the benefit of tty drivers */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | .c_iflag = ICRNL | IXON, |
| 115 | .c_oflag = OPOST | ONLCR, |
| 116 | .c_cflag = B38400 | CS8 | CREAD | HUPCL, |
| 117 | .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | |
| 118 | ECHOCTL | ECHOKE | IEXTEN, |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 119 | .c_cc = INIT_C_CC, |
| 120 | .c_ispeed = 38400, |
| 121 | .c_ospeed = 38400 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | }; |
| 123 | |
| 124 | EXPORT_SYMBOL(tty_std_termios); |
| 125 | |
| 126 | /* This list gets poked at by procfs and various bits of boot up code. This |
| 127 | could do with some rationalisation such as pulling the tty proc function |
| 128 | into this file */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 129 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | LIST_HEAD(tty_drivers); /* linked list of tty drivers */ |
| 131 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 132 | /* Mutex to protect creating and releasing a tty. This is shared with |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | vt.c for deeply disgusting hack reasons */ |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 134 | DEFINE_MUTEX(tty_mutex); |
Alan Cox | de2a84f | 2006-09-29 02:00:57 -0700 | [diff] [blame] | 135 | EXPORT_SYMBOL(tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 137 | /* Spinlock to protect the tty->tty_files list */ |
| 138 | DEFINE_SPINLOCK(tty_files_lock); |
| 139 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); |
| 141 | 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] | 142 | ssize_t redirected_tty_write(struct file *, const char __user *, |
| 143 | size_t, loff_t *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | static unsigned int tty_poll(struct file *, poll_table *); |
| 145 | static int tty_open(struct inode *, struct file *); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 146 | long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 147 | #ifdef CONFIG_COMPAT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 148 | static long tty_compat_ioctl(struct file *file, unsigned int cmd, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 149 | unsigned long arg); |
| 150 | #else |
| 151 | #define tty_compat_ioctl NULL |
| 152 | #endif |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 153 | static int __tty_fasync(int fd, struct file *filp, int on); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 154 | static int tty_fasync(int fd, struct file *filp, int on); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 155 | static void release_tty(struct tty_struct *tty, int idx); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 156 | static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty); |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 157 | static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 159 | /** |
| 160 | * alloc_tty_struct - allocate a tty object |
| 161 | * |
| 162 | * Return a new empty tty structure. The data fields have not |
| 163 | * been initialized in any way but has been zeroed |
| 164 | * |
| 165 | * Locking: none |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 166 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 168 | struct tty_struct *alloc_tty_struct(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | { |
Alan Cox | 1266b1e | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 170 | return kzalloc(sizeof(struct tty_struct), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | } |
| 172 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 173 | /** |
| 174 | * free_tty_struct - free a disused tty |
| 175 | * @tty: tty struct to free |
| 176 | * |
| 177 | * Free the write buffers, tty queue and tty memory itself. |
| 178 | * |
| 179 | * Locking: none. Must be called after tty is definitely unused |
| 180 | */ |
| 181 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 182 | void free_tty_struct(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | { |
Dan Carpenter | dc6802a | 2012-07-24 12:52:04 +0100 | [diff] [blame] | 184 | if (!tty) |
| 185 | return; |
Dmitry Eremin-Solenikov | 30004ac | 2010-08-09 18:22:49 +0400 | [diff] [blame] | 186 | if (tty->dev) |
| 187 | put_device(tty->dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | kfree(tty->write_buf); |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 189 | tty_buffer_free_all(tty); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 190 | tty->magic = 0xDEADDEAD; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | kfree(tty); |
| 192 | } |
| 193 | |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 194 | static inline struct tty_struct *file_tty(struct file *file) |
| 195 | { |
| 196 | return ((struct tty_file_private *)file->private_data)->tty; |
| 197 | } |
| 198 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 199 | int tty_alloc_file(struct file *file) |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 200 | { |
| 201 | struct tty_file_private *priv; |
| 202 | |
Pekka Enberg | f573bd1 | 2010-08-24 07:48:34 +0300 | [diff] [blame] | 203 | priv = kmalloc(sizeof(*priv), GFP_KERNEL); |
| 204 | if (!priv) |
| 205 | return -ENOMEM; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 206 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 207 | file->private_data = priv; |
| 208 | |
| 209 | return 0; |
| 210 | } |
| 211 | |
| 212 | /* Associate a new file with the tty structure */ |
| 213 | void tty_add_file(struct tty_struct *tty, struct file *file) |
| 214 | { |
| 215 | struct tty_file_private *priv = file->private_data; |
| 216 | |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 217 | priv->tty = tty; |
| 218 | priv->file = file; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 219 | |
| 220 | spin_lock(&tty_files_lock); |
| 221 | list_add(&priv->list, &tty->tty_files); |
| 222 | spin_unlock(&tty_files_lock); |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 223 | } |
Pekka Enberg | f573bd1 | 2010-08-24 07:48:34 +0300 | [diff] [blame] | 224 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 225 | /** |
| 226 | * tty_free_file - free file->private_data |
| 227 | * |
| 228 | * This shall be used only for fail path handling when tty_add_file was not |
| 229 | * called yet. |
| 230 | */ |
| 231 | void tty_free_file(struct file *file) |
| 232 | { |
| 233 | struct tty_file_private *priv = file->private_data; |
| 234 | |
| 235 | file->private_data = NULL; |
| 236 | kfree(priv); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 237 | } |
| 238 | |
| 239 | /* Delete file from its tty */ |
| 240 | void tty_del_file(struct file *file) |
| 241 | { |
| 242 | struct tty_file_private *priv = file->private_data; |
| 243 | |
| 244 | spin_lock(&tty_files_lock); |
| 245 | list_del(&priv->list); |
| 246 | spin_unlock(&tty_files_lock); |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 247 | tty_free_file(file); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 248 | } |
| 249 | |
| 250 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | #define TTY_NUMBER(tty) ((tty)->index + (tty)->driver->name_base) |
| 252 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 253 | /** |
| 254 | * tty_name - return tty naming |
| 255 | * @tty: tty structure |
| 256 | * @buf: buffer for output |
| 257 | * |
| 258 | * Convert a tty structure into a name. The name reflects the kernel |
| 259 | * naming policy and if udev is in use may not reflect user space |
| 260 | * |
| 261 | * Locking: none |
| 262 | */ |
| 263 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | char *tty_name(struct tty_struct *tty, char *buf) |
| 265 | { |
| 266 | if (!tty) /* Hmm. NULL pointer. That's fun. */ |
| 267 | strcpy(buf, "NULL tty"); |
| 268 | else |
| 269 | strcpy(buf, tty->name); |
| 270 | return buf; |
| 271 | } |
| 272 | |
| 273 | EXPORT_SYMBOL(tty_name); |
| 274 | |
Andrew Morton | d769a66 | 2005-05-05 16:15:50 -0700 | [diff] [blame] | 275 | int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | const char *routine) |
| 277 | { |
| 278 | #ifdef TTY_PARANOIA_CHECK |
| 279 | if (!tty) { |
| 280 | printk(KERN_WARNING |
| 281 | "null TTY for (%d:%d) in %s\n", |
| 282 | imajor(inode), iminor(inode), routine); |
| 283 | return 1; |
| 284 | } |
| 285 | if (tty->magic != TTY_MAGIC) { |
| 286 | printk(KERN_WARNING |
| 287 | "bad magic number for tty struct (%d:%d) in %s\n", |
| 288 | imajor(inode), iminor(inode), routine); |
| 289 | return 1; |
| 290 | } |
| 291 | #endif |
| 292 | return 0; |
| 293 | } |
| 294 | |
| 295 | static int check_tty_count(struct tty_struct *tty, const char *routine) |
| 296 | { |
| 297 | #ifdef CHECK_TTY_COUNT |
| 298 | struct list_head *p; |
| 299 | int count = 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 300 | |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 301 | spin_lock(&tty_files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | list_for_each(p, &tty->tty_files) { |
| 303 | count++; |
| 304 | } |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 305 | spin_unlock(&tty_files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 307 | tty->driver->subtype == PTY_TYPE_SLAVE && |
| 308 | tty->link && tty->link->count) |
| 309 | count++; |
| 310 | if (tty->count != count) { |
| 311 | printk(KERN_WARNING "Warning: dev (%s) tty->count(%d) " |
| 312 | "!= #fd's(%d) in %s\n", |
| 313 | tty->name, tty->count, count, routine); |
| 314 | return count; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 315 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | #endif |
| 317 | return 0; |
| 318 | } |
| 319 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 320 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 321 | * get_tty_driver - find device of a tty |
| 322 | * @dev_t: device identifier |
| 323 | * @index: returns the index of the tty |
| 324 | * |
| 325 | * This routine returns a tty driver structure, given a device number |
| 326 | * and also passes back the index number. |
| 327 | * |
| 328 | * Locking: caller must hold tty_mutex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 330 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | static struct tty_driver *get_tty_driver(dev_t device, int *index) |
| 332 | { |
| 333 | struct tty_driver *p; |
| 334 | |
| 335 | list_for_each_entry(p, &tty_drivers, tty_drivers) { |
| 336 | dev_t base = MKDEV(p->major, p->minor_start); |
| 337 | if (device < base || device >= base + p->num) |
| 338 | continue; |
| 339 | *index = device - base; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 340 | return tty_driver_kref_get(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | } |
| 342 | return NULL; |
| 343 | } |
| 344 | |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 345 | #ifdef CONFIG_CONSOLE_POLL |
| 346 | |
| 347 | /** |
| 348 | * tty_find_polling_driver - find device of a polled tty |
| 349 | * @name: name string to match |
| 350 | * @line: pointer to resulting tty line nr |
| 351 | * |
| 352 | * This routine returns a tty driver structure, given a name |
| 353 | * and the condition that the tty driver is capable of polled |
| 354 | * operation. |
| 355 | */ |
| 356 | struct tty_driver *tty_find_polling_driver(char *name, int *line) |
| 357 | { |
| 358 | struct tty_driver *p, *res = NULL; |
| 359 | int tty_line = 0; |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 360 | int len; |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 361 | char *str, *stp; |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 362 | |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 363 | for (str = name; *str; str++) |
| 364 | if ((*str >= '0' && *str <= '9') || *str == ',') |
| 365 | break; |
| 366 | if (!*str) |
| 367 | return NULL; |
| 368 | |
| 369 | len = str - name; |
| 370 | tty_line = simple_strtoul(str, &str, 10); |
| 371 | |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 372 | mutex_lock(&tty_mutex); |
| 373 | /* Search through the tty devices to look for a match */ |
| 374 | list_for_each_entry(p, &tty_drivers, tty_drivers) { |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 375 | if (strncmp(name, p->name, len) != 0) |
| 376 | continue; |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 377 | stp = str; |
| 378 | if (*stp == ',') |
| 379 | stp++; |
| 380 | if (*stp == '\0') |
| 381 | stp = NULL; |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 382 | |
Nathael Pajani | 6eb68d6 | 2010-09-02 16:06:16 +0200 | [diff] [blame] | 383 | if (tty_line >= 0 && tty_line < p->num && p->ops && |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 384 | p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 385 | res = tty_driver_kref_get(p); |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 386 | *line = tty_line; |
| 387 | break; |
| 388 | } |
| 389 | } |
| 390 | mutex_unlock(&tty_mutex); |
| 391 | |
| 392 | return res; |
| 393 | } |
| 394 | EXPORT_SYMBOL_GPL(tty_find_polling_driver); |
| 395 | #endif |
| 396 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 397 | /** |
| 398 | * tty_check_change - check for POSIX terminal changes |
| 399 | * @tty: tty to check |
| 400 | * |
| 401 | * If we try to write to, or set the state of, a terminal and we're |
| 402 | * not in the foreground, send a SIGTTOU. If the signal is blocked or |
| 403 | * ignored, go ahead and perform the operation. (POSIX 7.2) |
| 404 | * |
Alan Cox | 978e595 | 2008-04-30 00:53:59 -0700 | [diff] [blame] | 405 | * Locking: ctrl_lock |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 407 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 408 | int tty_check_change(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 410 | unsigned long flags; |
| 411 | int ret = 0; |
| 412 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | if (current->signal->tty != tty) |
| 414 | return 0; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 415 | |
| 416 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 417 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 418 | if (!tty->pgrp) { |
| 419 | printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n"); |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 420 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | } |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 422 | if (task_pgrp(current) == tty->pgrp) |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 423 | goto out_unlock; |
| 424 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | if (is_ignored(SIGTTOU)) |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 426 | goto out; |
| 427 | if (is_current_pgrp_orphaned()) { |
| 428 | ret = -EIO; |
| 429 | goto out; |
| 430 | } |
Oleg Nesterov | 040b636 | 2007-06-01 00:46:53 -0700 | [diff] [blame] | 431 | kill_pgrp(task_pgrp(current), SIGTTOU, 1); |
| 432 | set_thread_flag(TIF_SIGPENDING); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 433 | ret = -ERESTARTSYS; |
| 434 | out: |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 435 | return ret; |
| 436 | out_unlock: |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 437 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 438 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | } |
| 440 | |
| 441 | EXPORT_SYMBOL(tty_check_change); |
| 442 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 443 | 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] | 444 | size_t count, loff_t *ppos) |
| 445 | { |
| 446 | return 0; |
| 447 | } |
| 448 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 449 | 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] | 450 | size_t count, loff_t *ppos) |
| 451 | { |
| 452 | return -EIO; |
| 453 | } |
| 454 | |
| 455 | /* No kernel lock held - none needed ;) */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 456 | 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] | 457 | { |
| 458 | return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; |
| 459 | } |
| 460 | |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 461 | static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, |
| 462 | unsigned long arg) |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 463 | { |
| 464 | return cmd == TIOCSPGRP ? -ENOTTY : -EIO; |
| 465 | } |
| 466 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 467 | static long hung_up_tty_compat_ioctl(struct file *file, |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 468 | unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | { |
| 470 | return cmd == TIOCSPGRP ? -ENOTTY : -EIO; |
| 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, |
| 505 | }; |
| 506 | |
| 507 | static DEFINE_SPINLOCK(redirect_lock); |
| 508 | static struct file *redirect; |
| 509 | |
| 510 | /** |
| 511 | * tty_wakeup - request more data |
| 512 | * @tty: terminal |
| 513 | * |
| 514 | * Internal and external helper for wakeups of tty. This function |
| 515 | * informs the line discipline if present that the driver is ready |
| 516 | * to receive more output data. |
| 517 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 518 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 519 | void tty_wakeup(struct tty_struct *tty) |
| 520 | { |
| 521 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 522 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { |
| 524 | ld = tty_ldisc_ref(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 525 | if (ld) { |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 526 | if (ld->ops->write_wakeup) |
| 527 | ld->ops->write_wakeup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | tty_ldisc_deref(ld); |
| 529 | } |
| 530 | } |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 531 | wake_up_interruptible_poll(&tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | } |
| 533 | |
| 534 | EXPORT_SYMBOL_GPL(tty_wakeup); |
| 535 | |
| 536 | /** |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 537 | * __tty_hangup - actual handler for hangup events |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 538 | * @work: tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 539 | * |
Alan Cox | 1bad879 | 2008-07-22 23:38:04 +0100 | [diff] [blame] | 540 | * This can be called by the "eventd" kernel thread. That is process |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 541 | * synchronous but doesn't hold any locks, so we need to make sure we |
| 542 | * have the appropriate locks for what we're doing. |
| 543 | * |
| 544 | * The hangup event clears any pending redirections onto the hung up |
| 545 | * device. It ensures future writes will error and it does the needed |
| 546 | * line discipline hangup and signal delivery. The tty object itself |
| 547 | * remains intact. |
| 548 | * |
| 549 | * Locking: |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 550 | * BTM |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 551 | * redirect lock for undoing redirection |
| 552 | * file list lock for manipulating list of ttys |
| 553 | * tty_ldisc_lock from called functions |
| 554 | * termios_mutex resetting termios data |
| 555 | * tasklist_lock to walk task list for hangup event |
| 556 | * ->siglock to protect ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | */ |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 558 | void __tty_hangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 560 | struct file *cons_filp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | struct file *filp, *f = NULL; |
| 562 | struct task_struct *p; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 563 | struct tty_file_private *priv; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 564 | int closecount = 0, n; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 565 | unsigned long flags; |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 566 | int refs = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | |
| 568 | if (!tty) |
| 569 | return; |
| 570 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | |
| 572 | spin_lock(&redirect_lock); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 573 | if (redirect && file_tty(redirect) == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | f = redirect; |
| 575 | redirect = NULL; |
| 576 | } |
| 577 | spin_unlock(&redirect_lock); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 578 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 579 | tty_lock(tty); |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 580 | |
Jiri Slaby | acfa747 | 2010-11-29 10:16:54 +0100 | [diff] [blame] | 581 | /* some functions below drop BTM, so we need this bit */ |
| 582 | set_bit(TTY_HUPPING, &tty->flags); |
| 583 | |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 584 | /* inuse_filps is protected by the single tty lock, |
| 585 | this really needs to change if we want to flush the |
| 586 | workqueue with the lock held */ |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 587 | check_tty_count(tty, "tty_hangup"); |
Alan Cox | 36ba782 | 2009-11-30 13:18:51 +0000 | [diff] [blame] | 588 | |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 589 | spin_lock(&tty_files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | /* This breaks for file handles being sent over AF_UNIX sockets ? */ |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 591 | list_for_each_entry(priv, &tty->tty_files, list) { |
| 592 | filp = priv->file; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | if (filp->f_op->write == redirected_tty_write) |
| 594 | cons_filp = filp; |
| 595 | if (filp->f_op->write != tty_write) |
| 596 | continue; |
| 597 | closecount++; |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 598 | __tty_fasync(-1, filp, 0); /* can't block */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | filp->f_op = &hung_up_tty_fops; |
| 600 | } |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 601 | spin_unlock(&tty_files_lock); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 602 | |
Jiri Slaby | acfa747 | 2010-11-29 10:16:54 +0100 | [diff] [blame] | 603 | /* |
| 604 | * it drops BTM and thus races with reopen |
| 605 | * we protect the race by TTY_HUPPING |
| 606 | */ |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 607 | tty_ldisc_hangup(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 608 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | read_lock(&tasklist_lock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 610 | if (tty->session) { |
| 611 | do_each_pid_task(tty->session, PIDTYPE_SID, p) { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 612 | spin_lock_irq(&p->sighand->siglock); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 613 | if (p->signal->tty == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | p->signal->tty = NULL; |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 615 | /* We defer the dereferences outside fo |
| 616 | the tasklist lock */ |
| 617 | refs++; |
| 618 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 619 | if (!p->signal->leader) { |
| 620 | spin_unlock_irq(&p->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | continue; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 622 | } |
| 623 | __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); |
| 624 | __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 625 | put_pid(p->signal->tty_old_pgrp); /* A noop */ |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 626 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 627 | if (tty->pgrp) |
| 628 | p->signal->tty_old_pgrp = get_pid(tty->pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 629 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 630 | spin_unlock_irq(&p->sighand->siglock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 631 | } while_each_pid_task(tty->session, PIDTYPE_SID, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 632 | } |
| 633 | read_unlock(&tasklist_lock); |
| 634 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 635 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 636 | clear_bit(TTY_THROTTLED, &tty->flags); |
| 637 | clear_bit(TTY_PUSH, &tty->flags); |
| 638 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
Eric W. Biederman | d9c1e9a | 2007-03-18 12:45:44 -0600 | [diff] [blame] | 639 | put_pid(tty->session); |
| 640 | put_pid(tty->pgrp); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 641 | tty->session = NULL; |
| 642 | tty->pgrp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 643 | tty->ctrl_status = 0; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 644 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 645 | |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 646 | /* Account for the p->signal references we killed */ |
| 647 | while (refs--) |
| 648 | tty_kref_put(tty); |
| 649 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 650 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 651 | * If one of the devices matches a console pointer, we |
| 652 | * cannot just call hangup() because that will cause |
| 653 | * tty->count and state->count to go out of sync. |
| 654 | * So we just call close() the right number of times. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | */ |
| 656 | if (cons_filp) { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 657 | if (tty->ops->close) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | for (n = 0; n < closecount; n++) |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 659 | tty->ops->close(tty, cons_filp); |
| 660 | } else if (tty->ops->hangup) |
| 661 | (tty->ops->hangup)(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 662 | /* |
| 663 | * We don't want to have driver/ldisc interactions beyond |
| 664 | * the ones we did here. The driver layer expects no |
| 665 | * calls after ->hangup() from the ldisc side. However we |
| 666 | * can't yet guarantee all that. |
| 667 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | set_bit(TTY_HUPPED, &tty->flags); |
Jiri Slaby | acfa747 | 2010-11-29 10:16:54 +0100 | [diff] [blame] | 669 | clear_bit(TTY_HUPPING, &tty->flags); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 670 | tty_ldisc_enable(tty); |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 671 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 672 | tty_unlock(tty); |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 673 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 674 | if (f) |
| 675 | fput(f); |
| 676 | } |
| 677 | |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 678 | static void do_tty_hangup(struct work_struct *work) |
| 679 | { |
| 680 | struct tty_struct *tty = |
| 681 | container_of(work, struct tty_struct, hangup_work); |
| 682 | |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 683 | __tty_hangup(tty); |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 684 | } |
| 685 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 686 | /** |
| 687 | * tty_hangup - trigger a hangup event |
| 688 | * @tty: tty to hangup |
| 689 | * |
| 690 | * A carrier loss (virtual or otherwise) has occurred on this like |
| 691 | * schedule a hangup sequence to run after this event. |
| 692 | */ |
| 693 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 694 | void tty_hangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 695 | { |
| 696 | #ifdef TTY_DEBUG_HANGUP |
| 697 | char buf[64]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | printk(KERN_DEBUG "%s hangup...\n", tty_name(tty, buf)); |
| 699 | #endif |
| 700 | schedule_work(&tty->hangup_work); |
| 701 | } |
| 702 | |
| 703 | EXPORT_SYMBOL(tty_hangup); |
| 704 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 705 | /** |
| 706 | * tty_vhangup - process vhangup |
| 707 | * @tty: tty to hangup |
| 708 | * |
| 709 | * The user has asked via system call for the terminal to be hung up. |
| 710 | * 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] | 711 | * is complete. That guarantee is necessary for security reasons. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 712 | */ |
| 713 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 714 | void tty_vhangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 715 | { |
| 716 | #ifdef TTY_DEBUG_HANGUP |
| 717 | char buf[64]; |
| 718 | |
| 719 | printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty, buf)); |
| 720 | #endif |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 721 | __tty_hangup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 723 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | EXPORT_SYMBOL(tty_vhangup); |
| 725 | |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 726 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 727 | /** |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 728 | * tty_vhangup_self - process vhangup for own ctty |
| 729 | * |
| 730 | * Perform a vhangup on the current controlling tty |
| 731 | */ |
| 732 | |
| 733 | void tty_vhangup_self(void) |
| 734 | { |
| 735 | struct tty_struct *tty; |
| 736 | |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 737 | tty = get_current_tty(); |
| 738 | if (tty) { |
| 739 | tty_vhangup(tty); |
| 740 | tty_kref_put(tty); |
| 741 | } |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 742 | } |
| 743 | |
| 744 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 745 | * tty_hung_up_p - was tty hung up |
| 746 | * @filp: file pointer of tty |
| 747 | * |
| 748 | * Return true if the tty has been subject to a vhangup or a carrier |
| 749 | * loss |
| 750 | */ |
| 751 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 752 | int tty_hung_up_p(struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | { |
| 754 | return (filp->f_op == &hung_up_tty_fops); |
| 755 | } |
| 756 | |
| 757 | EXPORT_SYMBOL(tty_hung_up_p); |
| 758 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 759 | static void session_clear_tty(struct pid *session) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 760 | { |
| 761 | struct task_struct *p; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 762 | do_each_pid_task(session, PIDTYPE_SID, p) { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 763 | proc_clear_tty(p); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 764 | } while_each_pid_task(session, PIDTYPE_SID, p); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 765 | } |
| 766 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 767 | /** |
| 768 | * disassociate_ctty - disconnect controlling tty |
| 769 | * @on_exit: true if exiting so need to "hang up" the session |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 770 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 771 | * This function is typically called only by the session leader, when |
| 772 | * it wants to disassociate itself from its controlling tty. |
| 773 | * |
| 774 | * It performs the following functions: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | * (1) Sends a SIGHUP and SIGCONT to the foreground process group |
| 776 | * (2) Clears the tty from being controlling the session |
| 777 | * (3) Clears the controlling tty for all processes in the |
| 778 | * session group. |
| 779 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 780 | * The argument on_exit is set to 1 if called when a process is |
| 781 | * exiting; it is 0 if called by the ioctl TIOCNOTTY. |
| 782 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 783 | * Locking: |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 784 | * BTM is taken for hysterical raisins, and held when |
| 785 | * called from no_tty(). |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 786 | * tty_mutex is taken to protect tty |
| 787 | * ->siglock is taken to protect ->signal/->sighand |
| 788 | * tasklist_lock is taken to walk process list for sessions |
| 789 | * ->siglock is taken to protect ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 790 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 791 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 792 | void disassociate_ctty(int on_exit) |
| 793 | { |
| 794 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | |
Alan Cox | 5ec93d1 | 2009-11-30 13:18:45 +0000 | [diff] [blame] | 796 | if (!current->signal->leader) |
| 797 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 799 | tty = get_current_tty(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | if (tty) { |
Jiri Slaby | 1411dc4 | 2011-11-09 21:33:18 +0100 | [diff] [blame] | 801 | struct pid *tty_pgrp = get_pid(tty->pgrp); |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 802 | if (on_exit) { |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 803 | if (tty->driver->type != TTY_DRIVER_TYPE_PTY) |
Arnd Bergmann | 11dbf20 | 2010-06-18 14:58:07 +0200 | [diff] [blame] | 804 | tty_vhangup(tty); |
Arnd Bergmann | ddcd9fb | 2010-06-01 22:53:08 +0200 | [diff] [blame] | 805 | } |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 806 | tty_kref_put(tty); |
Jiri Slaby | 1411dc4 | 2011-11-09 21:33:18 +0100 | [diff] [blame] | 807 | if (tty_pgrp) { |
| 808 | kill_pgrp(tty_pgrp, SIGHUP, on_exit); |
| 809 | if (!on_exit) |
| 810 | kill_pgrp(tty_pgrp, SIGCONT, on_exit); |
| 811 | put_pid(tty_pgrp); |
| 812 | } |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 813 | } else if (on_exit) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 814 | struct pid *old_pgrp; |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 815 | spin_lock_irq(¤t->sighand->siglock); |
| 816 | old_pgrp = current->signal->tty_old_pgrp; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 817 | current->signal->tty_old_pgrp = NULL; |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 818 | spin_unlock_irq(¤t->sighand->siglock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 819 | if (old_pgrp) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 820 | kill_pgrp(old_pgrp, SIGHUP, on_exit); |
| 821 | kill_pgrp(old_pgrp, SIGCONT, on_exit); |
| 822 | put_pid(old_pgrp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 824 | return; |
| 825 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 826 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 827 | spin_lock_irq(¤t->sighand->siglock); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 828 | put_pid(current->signal->tty_old_pgrp); |
Randy Dunlap | 23cac8d | 2007-02-20 13:58:05 -0800 | [diff] [blame] | 829 | current->signal->tty_old_pgrp = NULL; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 830 | spin_unlock_irq(¤t->sighand->siglock); |
| 831 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 832 | tty = get_current_tty(); |
| 833 | if (tty) { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 834 | unsigned long flags; |
| 835 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 836 | put_pid(tty->session); |
| 837 | put_pid(tty->pgrp); |
| 838 | tty->session = NULL; |
| 839 | tty->pgrp = NULL; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 840 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 841 | tty_kref_put(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 842 | } else { |
| 843 | #ifdef TTY_DEBUG_HANGUP |
| 844 | printk(KERN_DEBUG "error attempted to write to tty [0x%p]" |
| 845 | " = NULL", tty); |
| 846 | #endif |
| 847 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 848 | |
| 849 | /* Now clear signal->tty under the lock */ |
| 850 | read_lock(&tasklist_lock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 851 | session_clear_tty(task_session(current)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | read_unlock(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | } |
| 854 | |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 855 | /** |
| 856 | * |
| 857 | * no_tty - Ensure the current process does not have a controlling tty |
| 858 | */ |
| 859 | void no_tty(void) |
| 860 | { |
Alan Cox | 3af502b | 2012-05-03 22:21:53 +0100 | [diff] [blame] | 861 | /* FIXME: Review locking here. The tty_lock never covered any race |
| 862 | between a new association and proc_clear_tty but possible we need |
| 863 | to protect against this anyway */ |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 864 | struct task_struct *tsk = current; |
Alan Cox | 5ec93d1 | 2009-11-30 13:18:45 +0000 | [diff] [blame] | 865 | disassociate_ctty(0); |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 866 | proc_clear_tty(tsk); |
| 867 | } |
| 868 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 869 | |
| 870 | /** |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 871 | * stop_tty - propagate flow control |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 872 | * @tty: tty to stop |
| 873 | * |
| 874 | * Perform flow control to the driver. For PTY/TTY pairs we |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 875 | * must also propagate the TIOCKPKT status. May be called |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 876 | * on an already stopped device and will not re-call the driver |
| 877 | * method. |
| 878 | * |
| 879 | * This functionality is used by both the line disciplines for |
| 880 | * halting incoming flow and by the driver. It may therefore be |
| 881 | * called from any context, may be under the tty atomic_write_lock |
| 882 | * but not always. |
| 883 | * |
| 884 | * Locking: |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 885 | * Uses the tty control lock internally |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 886 | */ |
| 887 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 888 | void stop_tty(struct tty_struct *tty) |
| 889 | { |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 890 | unsigned long flags; |
| 891 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 892 | if (tty->stopped) { |
| 893 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 894 | return; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 895 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | tty->stopped = 1; |
| 897 | if (tty->link && tty->link->packet) { |
| 898 | tty->ctrl_status &= ~TIOCPKT_START; |
| 899 | tty->ctrl_status |= TIOCPKT_STOP; |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 900 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 901 | } |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 902 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 903 | if (tty->ops->stop) |
| 904 | (tty->ops->stop)(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 905 | } |
| 906 | |
| 907 | EXPORT_SYMBOL(stop_tty); |
| 908 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 909 | /** |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 910 | * start_tty - propagate flow control |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 911 | * @tty: tty to start |
| 912 | * |
| 913 | * Start a tty that has been stopped if at all possible. Perform |
Robert P. J. Day | 3a4fa0a | 2007-10-19 23:10:43 +0200 | [diff] [blame] | 914 | * any necessary wakeups and propagate the TIOCPKT status. If this |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 915 | * is the tty was previous stopped and is being started then the |
| 916 | * driver start method is invoked and the line discipline woken. |
| 917 | * |
| 918 | * Locking: |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 919 | * ctrl_lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 920 | */ |
| 921 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 922 | void start_tty(struct tty_struct *tty) |
| 923 | { |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 924 | unsigned long flags; |
| 925 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 926 | if (!tty->stopped || tty->flow_stopped) { |
| 927 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 928 | return; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 929 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | tty->stopped = 0; |
| 931 | if (tty->link && tty->link->packet) { |
| 932 | tty->ctrl_status &= ~TIOCPKT_STOP; |
| 933 | tty->ctrl_status |= TIOCPKT_START; |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 934 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | } |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 936 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 937 | if (tty->ops->start) |
| 938 | (tty->ops->start)(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 939 | /* If we have a running line discipline it may need kicking */ |
| 940 | tty_wakeup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 941 | } |
| 942 | |
| 943 | EXPORT_SYMBOL(start_tty); |
| 944 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 945 | /** |
| 946 | * tty_read - read method for tty device files |
| 947 | * @file: pointer to tty file |
| 948 | * @buf: user buffer |
| 949 | * @count: size of user buffer |
| 950 | * @ppos: unused |
| 951 | * |
| 952 | * Perform the read system call function on this terminal device. Checks |
| 953 | * for hung up devices before calling the line discipline method. |
| 954 | * |
| 955 | * Locking: |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 956 | * Locks the line discipline internally while needed. Multiple |
| 957 | * read calls may be outstanding in parallel. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 958 | */ |
| 959 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 960 | 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] | 961 | loff_t *ppos) |
| 962 | { |
| 963 | int i; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 964 | struct inode *inode = file->f_path.dentry->d_inode; |
| 965 | struct tty_struct *tty = file_tty(file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | struct tty_ldisc *ld; |
| 967 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 968 | if (tty_paranoia_check(tty, inode, "tty_read")) |
| 969 | return -EIO; |
| 970 | if (!tty || (test_bit(TTY_IO_ERROR, &tty->flags))) |
| 971 | return -EIO; |
| 972 | |
| 973 | /* We want to wait for the line discipline to sort out in this |
| 974 | situation */ |
| 975 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 976 | if (ld->ops->read) |
| 977 | i = (ld->ops->read)(tty, file, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 978 | else |
| 979 | i = -EIO; |
| 980 | tty_ldisc_deref(ld); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 981 | if (i > 0) |
| 982 | inode->i_atime = current_fs_time(inode->i_sb); |
| 983 | return i; |
| 984 | } |
| 985 | |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 986 | void tty_write_unlock(struct tty_struct *tty) |
Jiri Slaby | 83c6757 | 2011-04-20 10:43:18 +0200 | [diff] [blame] | 987 | __releases(&tty->atomic_write_lock) |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 988 | { |
| 989 | mutex_unlock(&tty->atomic_write_lock); |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 990 | wake_up_interruptible_poll(&tty->write_wait, POLLOUT); |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 991 | } |
| 992 | |
| 993 | int tty_write_lock(struct tty_struct *tty, int ndelay) |
Jiri Slaby | 83c6757 | 2011-04-20 10:43:18 +0200 | [diff] [blame] | 994 | __acquires(&tty->atomic_write_lock) |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 995 | { |
| 996 | if (!mutex_trylock(&tty->atomic_write_lock)) { |
| 997 | if (ndelay) |
| 998 | return -EAGAIN; |
| 999 | if (mutex_lock_interruptible(&tty->atomic_write_lock)) |
| 1000 | return -ERESTARTSYS; |
| 1001 | } |
| 1002 | return 0; |
| 1003 | } |
| 1004 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1005 | /* |
| 1006 | * Split writes up in sane blocksizes to avoid |
| 1007 | * denial-of-service type attacks |
| 1008 | */ |
| 1009 | static inline ssize_t do_tty_write( |
| 1010 | ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), |
| 1011 | struct tty_struct *tty, |
| 1012 | struct file *file, |
| 1013 | const char __user *buf, |
| 1014 | size_t count) |
| 1015 | { |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1016 | ssize_t ret, written = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1017 | unsigned int chunk; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1018 | |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1019 | ret = tty_write_lock(tty, file->f_flags & O_NDELAY); |
| 1020 | if (ret < 0) |
| 1021 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1022 | |
| 1023 | /* |
| 1024 | * We chunk up writes into a temporary buffer. This |
| 1025 | * simplifies low-level drivers immensely, since they |
| 1026 | * don't have locking issues and user mode accesses. |
| 1027 | * |
| 1028 | * But if TTY_NO_WRITE_SPLIT is set, we should use a |
| 1029 | * big chunk-size.. |
| 1030 | * |
| 1031 | * The default chunk-size is 2kB, because the NTTY |
| 1032 | * layer has problems with bigger chunks. It will |
| 1033 | * claim to be able to handle more characters than |
| 1034 | * it actually does. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1035 | * |
| 1036 | * FIXME: This can probably go away now except that 64K chunks |
| 1037 | * are too likely to fail unless switched to vmalloc... |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | */ |
| 1039 | chunk = 2048; |
| 1040 | if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) |
| 1041 | chunk = 65536; |
| 1042 | if (count < chunk) |
| 1043 | chunk = count; |
| 1044 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1045 | /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1046 | if (tty->write_cnt < chunk) { |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 1047 | unsigned char *buf_chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1048 | |
| 1049 | if (chunk < 1024) |
| 1050 | chunk = 1024; |
| 1051 | |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 1052 | buf_chunk = kmalloc(chunk, GFP_KERNEL); |
| 1053 | if (!buf_chunk) { |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1054 | ret = -ENOMEM; |
| 1055 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1056 | } |
| 1057 | kfree(tty->write_buf); |
| 1058 | tty->write_cnt = chunk; |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 1059 | tty->write_buf = buf_chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1060 | } |
| 1061 | |
| 1062 | /* Do the write .. */ |
| 1063 | for (;;) { |
| 1064 | size_t size = count; |
| 1065 | if (size > chunk) |
| 1066 | size = chunk; |
| 1067 | ret = -EFAULT; |
| 1068 | if (copy_from_user(tty->write_buf, buf, size)) |
| 1069 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | ret = write(tty, file, tty->write_buf, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1071 | if (ret <= 0) |
| 1072 | break; |
| 1073 | written += ret; |
| 1074 | buf += ret; |
| 1075 | count -= ret; |
| 1076 | if (!count) |
| 1077 | break; |
| 1078 | ret = -ERESTARTSYS; |
| 1079 | if (signal_pending(current)) |
| 1080 | break; |
| 1081 | cond_resched(); |
| 1082 | } |
| 1083 | if (written) { |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 1084 | struct inode *inode = file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1085 | inode->i_mtime = current_fs_time(inode->i_sb); |
| 1086 | ret = written; |
| 1087 | } |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1088 | out: |
| 1089 | tty_write_unlock(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1090 | return ret; |
| 1091 | } |
| 1092 | |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1093 | /** |
| 1094 | * tty_write_message - write a message to a certain tty, not just the console. |
| 1095 | * @tty: the destination tty_struct |
| 1096 | * @msg: the message to write |
| 1097 | * |
| 1098 | * This is used for messages that need to be redirected to a specific tty. |
| 1099 | * We don't put it into the syslog queue right now maybe in the future if |
| 1100 | * really needed. |
| 1101 | * |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 1102 | * 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] | 1103 | */ |
| 1104 | |
| 1105 | void tty_write_message(struct tty_struct *tty, char *msg) |
| 1106 | { |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1107 | if (tty) { |
| 1108 | mutex_lock(&tty->atomic_write_lock); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1109 | tty_lock(tty); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1110 | if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) { |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1111 | tty_unlock(tty); |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1112 | tty->ops->write(tty, msg, strlen(msg)); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1113 | } else |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1114 | tty_unlock(tty); |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1115 | tty_write_unlock(tty); |
| 1116 | } |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1117 | return; |
| 1118 | } |
| 1119 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1120 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1121 | /** |
| 1122 | * tty_write - write method for tty device file |
| 1123 | * @file: tty file pointer |
| 1124 | * @buf: user data to write |
| 1125 | * @count: bytes to write |
| 1126 | * @ppos: unused |
| 1127 | * |
| 1128 | * Write data to a tty device via the line discipline. |
| 1129 | * |
| 1130 | * Locking: |
| 1131 | * Locks the line discipline as required |
| 1132 | * Writes to the tty driver are serialized by the atomic_write_lock |
| 1133 | * and are then processed in chunks to the device. The line discipline |
Joe Peterson | a88a69c | 2009-01-02 13:40:53 +0000 | [diff] [blame] | 1134 | * write method will not be invoked in parallel for each device. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1135 | */ |
| 1136 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1137 | static ssize_t tty_write(struct file *file, const char __user *buf, |
| 1138 | size_t count, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1139 | { |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 1140 | struct inode *inode = file->f_path.dentry->d_inode; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1141 | struct tty_struct *tty = file_tty(file); |
| 1142 | struct tty_ldisc *ld; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | ssize_t ret; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1144 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1145 | if (tty_paranoia_check(tty, inode, "tty_write")) |
| 1146 | return -EIO; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1147 | if (!tty || !tty->ops->write || |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1148 | (test_bit(TTY_IO_ERROR, &tty->flags))) |
| 1149 | return -EIO; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1150 | /* Short term debug to catch buggy drivers */ |
| 1151 | if (tty->ops->write_room == NULL) |
| 1152 | printk(KERN_ERR "tty driver %s lacks a write_room method.\n", |
| 1153 | tty->driver->name); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1154 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1155 | if (!ld->ops->write) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1156 | ret = -EIO; |
| 1157 | else |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1158 | ret = do_tty_write(ld->ops->write, tty, file, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1159 | tty_ldisc_deref(ld); |
| 1160 | return ret; |
| 1161 | } |
| 1162 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1163 | ssize_t redirected_tty_write(struct file *file, const char __user *buf, |
| 1164 | size_t count, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | { |
| 1166 | struct file *p = NULL; |
| 1167 | |
| 1168 | spin_lock(&redirect_lock); |
| 1169 | if (redirect) { |
| 1170 | get_file(redirect); |
| 1171 | p = redirect; |
| 1172 | } |
| 1173 | spin_unlock(&redirect_lock); |
| 1174 | |
| 1175 | if (p) { |
| 1176 | ssize_t res; |
| 1177 | res = vfs_write(p, buf, count, &p->f_pos); |
| 1178 | fput(p); |
| 1179 | return res; |
| 1180 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | return tty_write(file, buf, count, ppos); |
| 1182 | } |
| 1183 | |
| 1184 | static char ptychar[] = "pqrstuvwxyzabcde"; |
| 1185 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1186 | /** |
| 1187 | * pty_line_name - generate name for a pty |
| 1188 | * @driver: the tty driver in use |
| 1189 | * @index: the minor number |
| 1190 | * @p: output buffer of at least 6 bytes |
| 1191 | * |
| 1192 | * Generate a name from a driver reference and write it to the output |
| 1193 | * buffer. |
| 1194 | * |
| 1195 | * Locking: None |
| 1196 | */ |
| 1197 | 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] | 1198 | { |
| 1199 | int i = index + driver->name_base; |
| 1200 | /* ->name is initialized to "ttyp", but "tty" is expected */ |
| 1201 | sprintf(p, "%s%c%x", |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1202 | driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, |
| 1203 | ptychar[i >> 4 & 0xf], i & 0xf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1204 | } |
| 1205 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1206 | /** |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1207 | * tty_line_name - generate name for a tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1208 | * @driver: the tty driver in use |
| 1209 | * @index: the minor number |
| 1210 | * @p: output buffer of at least 7 bytes |
| 1211 | * |
| 1212 | * Generate a name from a driver reference and write it to the output |
| 1213 | * buffer. |
| 1214 | * |
| 1215 | * Locking: None |
| 1216 | */ |
| 1217 | static void tty_line_name(struct tty_driver *driver, int index, char *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1218 | { |
Jiri Slaby | 0019b40 | 2012-08-08 22:26:43 +0200 | [diff] [blame] | 1219 | if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE) |
| 1220 | strcpy(p, driver->name); |
| 1221 | else |
| 1222 | sprintf(p, "%s%d", driver->name, index + driver->name_base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1223 | } |
| 1224 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1225 | /** |
| 1226 | * tty_driver_lookup_tty() - find an existing tty, if any |
| 1227 | * @driver: the driver for the tty |
| 1228 | * @idx: the minor number |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1229 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1230 | * Return the tty, if found or ERR_PTR() otherwise. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1231 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1232 | * Locking: tty_mutex must be held. If tty is found, the mutex must |
| 1233 | * be held until the 'fast-open' is also done. Will change once we |
| 1234 | * have refcounting in the driver and per driver locking |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1235 | */ |
Jason Wessel | a47d545 | 2009-01-02 13:43:04 +0000 | [diff] [blame] | 1236 | static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1237 | struct inode *inode, int idx) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1238 | { |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1239 | if (driver->ops->lookup) |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1240 | return driver->ops->lookup(driver, inode, idx); |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1241 | |
Jiri Slaby | d483426 | 2012-03-05 14:51:53 +0100 | [diff] [blame] | 1242 | return driver->ttys[idx]; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1243 | } |
| 1244 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1245 | /** |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1246 | * tty_init_termios - helper for termios setup |
| 1247 | * @tty: the tty to set up |
| 1248 | * |
| 1249 | * Initialise the termios structures for this tty. Thus runs under |
| 1250 | * the tty_mutex currently so we can be relaxed about ordering. |
| 1251 | */ |
| 1252 | |
| 1253 | int tty_init_termios(struct tty_struct *tty) |
| 1254 | { |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 1255 | struct ktermios *tp; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1256 | int idx = tty->index; |
| 1257 | |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1258 | if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) |
| 1259 | tty->termios = tty->driver->init_termios; |
| 1260 | else { |
| 1261 | /* Check for lazy saved data */ |
| 1262 | tp = tty->driver->termios[idx]; |
| 1263 | if (tp != NULL) |
| 1264 | tty->termios = *tp; |
| 1265 | else |
| 1266 | tty->termios = tty->driver->init_termios; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1267 | } |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1268 | /* Compatibility until drivers always set this */ |
Alan Cox | adc8d74 | 2012-07-14 15:31:47 +0100 | [diff] [blame] | 1269 | tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios); |
| 1270 | tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1271 | return 0; |
| 1272 | } |
Alan Cox | fe1ae7f | 2009-09-19 13:13:33 -0700 | [diff] [blame] | 1273 | EXPORT_SYMBOL_GPL(tty_init_termios); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1274 | |
Jiri Slaby | 66d450e | 2012-01-30 21:14:28 +0100 | [diff] [blame] | 1275 | int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty) |
| 1276 | { |
| 1277 | int ret = tty_init_termios(tty); |
| 1278 | if (ret) |
| 1279 | return ret; |
| 1280 | |
| 1281 | tty_driver_kref_get(driver); |
| 1282 | tty->count++; |
| 1283 | driver->ttys[tty->index] = tty; |
| 1284 | return 0; |
| 1285 | } |
| 1286 | EXPORT_SYMBOL_GPL(tty_standard_install); |
| 1287 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1288 | /** |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1289 | * tty_driver_install_tty() - install a tty entry in the driver |
| 1290 | * @driver: the driver for the tty |
| 1291 | * @tty: the tty |
| 1292 | * |
| 1293 | * Install a tty object into the driver tables. The tty->index field |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1294 | * will be set by the time this is called. This method is responsible |
| 1295 | * for ensuring any need additional structures are allocated and |
| 1296 | * configured. |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1297 | * |
| 1298 | * Locking: tty_mutex for now |
| 1299 | */ |
| 1300 | static int tty_driver_install_tty(struct tty_driver *driver, |
| 1301 | struct tty_struct *tty) |
| 1302 | { |
Jiri Slaby | 66d450e | 2012-01-30 21:14:28 +0100 | [diff] [blame] | 1303 | return driver->ops->install ? driver->ops->install(driver, tty) : |
| 1304 | tty_standard_install(driver, tty); |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1305 | } |
| 1306 | |
| 1307 | /** |
| 1308 | * tty_driver_remove_tty() - remove a tty from the driver tables |
| 1309 | * @driver: the driver for the tty |
| 1310 | * @idx: the minor number |
| 1311 | * |
| 1312 | * Remvoe a tty object from the driver tables. The tty->index field |
| 1313 | * will be set by the time this is called. |
| 1314 | * |
| 1315 | * Locking: tty_mutex for now |
| 1316 | */ |
Jiri Slaby | 24d406a | 2011-08-10 14:59:28 +0200 | [diff] [blame] | 1317 | 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] | 1318 | { |
| 1319 | if (driver->ops->remove) |
| 1320 | driver->ops->remove(driver, tty); |
| 1321 | else |
| 1322 | driver->ttys[tty->index] = NULL; |
| 1323 | } |
| 1324 | |
| 1325 | /* |
| 1326 | * tty_reopen() - fast re-open of an open tty |
| 1327 | * @tty - the tty to open |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1328 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1329 | * Return 0 on success, -errno on error. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1330 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1331 | * Locking: tty_mutex must be held from the time the tty was found |
| 1332 | * till this open completes. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1333 | */ |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1334 | static int tty_reopen(struct tty_struct *tty) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1335 | { |
| 1336 | struct tty_driver *driver = tty->driver; |
| 1337 | |
Jiri Slaby | e2efafb | 2010-11-29 10:16:53 +0100 | [diff] [blame] | 1338 | if (test_bit(TTY_CLOSING, &tty->flags) || |
Jiri Slaby | acfa747 | 2010-11-29 10:16:54 +0100 | [diff] [blame] | 1339 | test_bit(TTY_HUPPING, &tty->flags) || |
Jiri Slaby | e2efafb | 2010-11-29 10:16:53 +0100 | [diff] [blame] | 1340 | test_bit(TTY_LDISC_CHANGING, &tty->flags)) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1341 | return -EIO; |
| 1342 | |
| 1343 | if (driver->type == TTY_DRIVER_TYPE_PTY && |
| 1344 | driver->subtype == PTY_TYPE_MASTER) { |
| 1345 | /* |
| 1346 | * special case for PTY masters: only one open permitted, |
| 1347 | * and the slave side open count is incremented as well. |
| 1348 | */ |
| 1349 | if (tty->count) |
| 1350 | return -EIO; |
| 1351 | |
| 1352 | tty->link->count++; |
| 1353 | } |
| 1354 | tty->count++; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1355 | |
Alan Cox | 1aa4bed | 2009-06-16 17:01:33 +0100 | [diff] [blame] | 1356 | mutex_lock(&tty->ldisc_mutex); |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1357 | WARN_ON(!test_bit(TTY_LDISC, &tty->flags)); |
Alan Cox | 1aa4bed | 2009-06-16 17:01:33 +0100 | [diff] [blame] | 1358 | mutex_unlock(&tty->ldisc_mutex); |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1359 | |
| 1360 | return 0; |
| 1361 | } |
| 1362 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1363 | /** |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1364 | * tty_init_dev - initialise a tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1365 | * @driver: tty driver we are opening a device on |
| 1366 | * @idx: device index |
Alan Cox | 15582d3 | 2008-10-13 10:41:03 +0100 | [diff] [blame] | 1367 | * @ret_tty: returned tty structure |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1368 | * |
| 1369 | * Prepare a tty device. This may not be a "new" clean device but |
| 1370 | * could also be an active device. The pty drivers require special |
| 1371 | * handling because of this. |
| 1372 | * |
| 1373 | * Locking: |
| 1374 | * The function is called under the tty_mutex, which |
| 1375 | * protects us from the tty struct or driver itself going away. |
| 1376 | * |
| 1377 | * On exit the tty device has the line discipline attached and |
| 1378 | * a reference count of 1. If a pair was created for pty/tty use |
| 1379 | * and the other was a pty master then it too has a reference count of 1. |
| 1380 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1381 | * 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] | 1382 | * failed open. The new code protects the open with a mutex, so it's |
| 1383 | * really quite straightforward. The mutex locking can probably be |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1384 | * relaxed for the (most common) case of reopening a tty. |
| 1385 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1386 | |
Konstantin Khlebnikov | 593a27c | 2012-01-05 13:04:21 +0400 | [diff] [blame] | 1387 | struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1388 | { |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1389 | struct tty_struct *tty; |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1390 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1391 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1392 | /* |
| 1393 | * First time open is complex, especially for PTY devices. |
| 1394 | * This code guarantees that either everything succeeds and the |
| 1395 | * TTY is ready for operation, or else the table slots are vacated |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1396 | * and the allocated memory released. (Except that the termios |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1397 | * and locked termios may be retained.) |
| 1398 | */ |
| 1399 | |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1400 | if (!try_module_get(driver->owner)) |
| 1401 | return ERR_PTR(-ENODEV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1402 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1403 | tty = alloc_tty_struct(); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1404 | if (!tty) { |
| 1405 | retval = -ENOMEM; |
| 1406 | goto err_module_put; |
| 1407 | } |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1408 | initialize_tty_struct(tty, driver, idx); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1409 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1410 | tty_lock(tty); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1411 | retval = tty_driver_install_tty(driver, tty); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1412 | if (retval < 0) |
Jiri Slaby | a9dccdd | 2011-03-23 10:48:36 +0100 | [diff] [blame] | 1413 | goto err_deinit_tty; |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1414 | |
Jiri Slaby | 04831dc | 2012-06-04 13:35:36 +0200 | [diff] [blame] | 1415 | if (!tty->port) |
| 1416 | tty->port = driver->ports[idx]; |
| 1417 | |
Jiri Slaby | 5d4121c | 2012-08-17 14:27:52 +0200 | [diff] [blame] | 1418 | WARN_RATELIMIT(!tty->port, |
| 1419 | "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", |
| 1420 | __func__, tty->driver->name); |
| 1421 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1422 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1423 | * Structures all installed ... call the ldisc open routines. |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1424 | * If we fail here just call release_tty to clean up. No need |
| 1425 | * to decrement the use counts, as release_tty doesn't care. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1426 | */ |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1427 | retval = tty_ldisc_setup(tty, tty->link); |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1428 | if (retval) |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1429 | goto err_release_tty; |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1430 | /* Return the tty locked so that it cannot vanish under the caller */ |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1431 | return tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1432 | |
Jiri Slaby | a9dccdd | 2011-03-23 10:48:36 +0100 | [diff] [blame] | 1433 | err_deinit_tty: |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1434 | tty_unlock(tty); |
Jiri Slaby | a9dccdd | 2011-03-23 10:48:36 +0100 | [diff] [blame] | 1435 | deinitialize_tty_struct(tty); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1436 | free_tty_struct(tty); |
| 1437 | err_module_put: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1438 | module_put(driver->owner); |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1439 | return ERR_PTR(retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1440 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1441 | /* call the tty release_tty routine to clean out this slot */ |
Jiri Slaby | d554350 | 2011-03-23 10:48:32 +0100 | [diff] [blame] | 1442 | err_release_tty: |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1443 | tty_unlock(tty); |
Manuel Zerpies | 5a3c6b2 | 2011-06-16 14:07:22 +0200 | [diff] [blame] | 1444 | printk_ratelimited(KERN_INFO "tty_init_dev: ldisc open failed, " |
Akinobu Mita | 4050914 | 2006-09-29 02:01:27 -0700 | [diff] [blame] | 1445 | "clearing slot %d\n", idx); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1446 | release_tty(tty, idx); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1447 | return ERR_PTR(retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1448 | } |
| 1449 | |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1450 | void tty_free_termios(struct tty_struct *tty) |
| 1451 | { |
| 1452 | struct ktermios *tp; |
| 1453 | int idx = tty->index; |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1454 | |
| 1455 | /* If the port is going to reset then it has no termios to save */ |
| 1456 | if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) |
| 1457 | return; |
| 1458 | |
| 1459 | /* Stash the termios data */ |
| 1460 | tp = tty->driver->termios[idx]; |
| 1461 | if (tp == NULL) { |
| 1462 | tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL); |
| 1463 | if (tp == NULL) { |
| 1464 | pr_warn("tty: no memory to save termios state.\n"); |
| 1465 | return; |
| 1466 | } |
Dan Carpenter | 4ac5d70 | 2012-07-24 12:51:52 +0100 | [diff] [blame] | 1467 | tty->driver->termios[idx] = tp; |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1468 | } |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1469 | *tp = tty->termios; |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1470 | } |
| 1471 | EXPORT_SYMBOL(tty_free_termios); |
| 1472 | |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1473 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1474 | /** |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1475 | * release_one_tty - release tty structure memory |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1476 | * @kref: kref of tty we are obliterating |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1477 | * |
| 1478 | * Releases memory associated with a tty structure, and clears out the |
| 1479 | * driver table slots. This function is called when a device is no longer |
| 1480 | * in use. It also gets called when setup of a device fails. |
| 1481 | * |
| 1482 | * Locking: |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1483 | * takes the file list lock internally when working on the list |
| 1484 | * of ttys that the driver keeps. |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1485 | * |
| 1486 | * 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] | 1487 | * cleanup ops can sleep (needed for USB at least) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1488 | */ |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1489 | static void release_one_tty(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1490 | { |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1491 | struct tty_struct *tty = |
| 1492 | container_of(work, struct tty_struct, hangup_work); |
Alan Cox | 6f967f7 | 2008-10-13 10:37:36 +0100 | [diff] [blame] | 1493 | struct tty_driver *driver = tty->driver; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1494 | |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1495 | if (tty->ops->cleanup) |
| 1496 | tty->ops->cleanup(tty); |
| 1497 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1498 | tty->magic = 0; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 1499 | tty_driver_kref_put(driver); |
Alan Cox | 6f967f7 | 2008-10-13 10:37:36 +0100 | [diff] [blame] | 1500 | module_put(driver->owner); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1501 | |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 1502 | spin_lock(&tty_files_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1503 | list_del_init(&tty->tty_files); |
Nick Piggin | ee2ffa0 | 2010-08-18 04:37:35 +1000 | [diff] [blame] | 1504 | spin_unlock(&tty_files_lock); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1505 | |
Oleg Nesterov | 6da8d86 | 2010-04-02 18:05:12 +0200 | [diff] [blame] | 1506 | put_pid(tty->pgrp); |
| 1507 | put_pid(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1508 | free_tty_struct(tty); |
| 1509 | } |
| 1510 | |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1511 | static void queue_release_one_tty(struct kref *kref) |
| 1512 | { |
| 1513 | struct tty_struct *tty = container_of(kref, struct tty_struct, kref); |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1514 | |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1515 | /* The hangup queue is now free so we can reuse it rather than |
| 1516 | waste a chunk of memory for each port */ |
| 1517 | INIT_WORK(&tty->hangup_work, release_one_tty); |
| 1518 | schedule_work(&tty->hangup_work); |
| 1519 | } |
| 1520 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1521 | /** |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1522 | * tty_kref_put - release a tty kref |
| 1523 | * @tty: tty device |
| 1524 | * |
| 1525 | * Release a reference to a tty device and if need be let the kref |
| 1526 | * layer destruct the object for us |
| 1527 | */ |
| 1528 | |
| 1529 | void tty_kref_put(struct tty_struct *tty) |
| 1530 | { |
| 1531 | if (tty) |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1532 | kref_put(&tty->kref, queue_release_one_tty); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1533 | } |
| 1534 | EXPORT_SYMBOL(tty_kref_put); |
| 1535 | |
| 1536 | /** |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1537 | * release_tty - release tty structure memory |
| 1538 | * |
| 1539 | * Release both @tty and a possible linked partner (think pty pair), |
| 1540 | * and decrement the refcount of the backing module. |
| 1541 | * |
| 1542 | * Locking: |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1543 | * tty_mutex |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1544 | * takes the file list lock internally when working on the list |
| 1545 | * of ttys that the driver keeps. |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1546 | * |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1547 | */ |
| 1548 | static void release_tty(struct tty_struct *tty, int idx) |
| 1549 | { |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1550 | /* This should always be true but check for the moment */ |
| 1551 | WARN_ON(tty->index != idx); |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1552 | WARN_ON(!mutex_is_locked(&tty_mutex)); |
Alan Cox | 36b3c07 | 2012-07-17 17:06:57 +0100 | [diff] [blame] | 1553 | if (tty->ops->shutdown) |
| 1554 | tty->ops->shutdown(tty); |
| 1555 | tty_free_termios(tty); |
| 1556 | tty_driver_remove_tty(tty->driver, tty); |
| 1557 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1558 | if (tty->link) |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1559 | tty_kref_put(tty->link); |
| 1560 | tty_kref_put(tty); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1561 | } |
| 1562 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1563 | /** |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1564 | * tty_release_checks - check a tty before real release |
| 1565 | * @tty: tty to check |
| 1566 | * @o_tty: link of @tty (if any) |
| 1567 | * @idx: index of the tty |
| 1568 | * |
| 1569 | * Performs some paranoid checking before true release of the @tty. |
| 1570 | * This is a no-op unless TTY_PARANOIA_CHECK is defined. |
| 1571 | */ |
| 1572 | static int tty_release_checks(struct tty_struct *tty, struct tty_struct *o_tty, |
| 1573 | int idx) |
| 1574 | { |
| 1575 | #ifdef TTY_PARANOIA_CHECK |
| 1576 | if (idx < 0 || idx >= tty->driver->num) { |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1577 | printk(KERN_DEBUG "%s: bad idx when trying to free (%s)\n", |
| 1578 | __func__, tty->name); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1579 | return -1; |
| 1580 | } |
| 1581 | |
| 1582 | /* not much to check for devpts */ |
| 1583 | if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) |
| 1584 | return 0; |
| 1585 | |
| 1586 | if (tty != tty->driver->ttys[idx]) { |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1587 | printk(KERN_DEBUG "%s: driver.table[%d] not tty for (%s)\n", |
| 1588 | __func__, idx, tty->name); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1589 | return -1; |
| 1590 | } |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1591 | if (tty->driver->other) { |
| 1592 | if (o_tty != tty->driver->other->ttys[idx]) { |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1593 | printk(KERN_DEBUG "%s: other->table[%d] not o_tty for (%s)\n", |
| 1594 | __func__, idx, tty->name); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1595 | return -1; |
| 1596 | } |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1597 | if (o_tty->link != tty) { |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1598 | printk(KERN_DEBUG "%s: bad pty pointers\n", __func__); |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1599 | return -1; |
| 1600 | } |
| 1601 | } |
| 1602 | #endif |
| 1603 | return 0; |
| 1604 | } |
| 1605 | |
| 1606 | /** |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1607 | * tty_release - vfs callback for close |
| 1608 | * @inode: inode of tty |
| 1609 | * @filp: file pointer for handle to tty |
| 1610 | * |
| 1611 | * Called the last time each file handle is closed that references |
| 1612 | * this tty. There may however be several such references. |
| 1613 | * |
| 1614 | * Locking: |
| 1615 | * Takes bkl. See tty_release_dev |
| 1616 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1617 | * Even releasing the tty structures is a tricky business.. We have |
| 1618 | * to be very careful that the structures are all released at the |
| 1619 | * same time, as interrupts might otherwise get the wrong pointers. |
| 1620 | * |
| 1621 | * WSH 09/09/97: rewritten to avoid some nasty race conditions that could |
| 1622 | * lead to double frees or releasing memory still in use. |
| 1623 | */ |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1624 | |
| 1625 | int tty_release(struct inode *inode, struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1626 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1627 | struct tty_struct *tty = file_tty(filp); |
| 1628 | struct tty_struct *o_tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1629 | int pty_master, tty_closing, o_tty_closing, do_sleep; |
Paul Fulghum | 14a6283 | 2006-04-10 22:54:19 -0700 | [diff] [blame] | 1630 | int devpts; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1631 | int idx; |
| 1632 | char buf[64]; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1633 | |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1634 | if (tty_paranoia_check(tty, inode, __func__)) |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1635 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1636 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1637 | tty_lock(tty); |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1638 | check_tty_count(tty, __func__); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1639 | |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 1640 | __tty_fasync(-1, filp, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1641 | |
| 1642 | idx = tty->index; |
| 1643 | pty_master = (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 1644 | tty->driver->subtype == PTY_TYPE_MASTER); |
| 1645 | devpts = (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) != 0; |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1646 | /* Review: parallel close */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1647 | o_tty = tty->link; |
| 1648 | |
Jiri Slaby | 955787ca | 2011-11-11 10:47:23 +0100 | [diff] [blame] | 1649 | if (tty_release_checks(tty, o_tty, idx)) { |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1650 | tty_unlock(tty); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1651 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1652 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1653 | |
| 1654 | #ifdef TTY_DEBUG_HANGUP |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1655 | printk(KERN_DEBUG "%s: %s (tty count=%d)...\n", __func__, |
| 1656 | tty_name(tty, buf), tty->count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1657 | #endif |
| 1658 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1659 | if (tty->ops->close) |
| 1660 | tty->ops->close(tty, filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1661 | |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1662 | tty_unlock(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1663 | /* |
| 1664 | * Sanity check: if tty->count is going to zero, there shouldn't be |
| 1665 | * any waiters on tty->read_wait or tty->write_wait. We test the |
| 1666 | * wait queues and kick everyone out _before_ actually starting to |
| 1667 | * close. This ensures that we won't block while releasing the tty |
| 1668 | * structure. |
| 1669 | * |
| 1670 | * The test for the o_tty closing is necessary, since the master and |
| 1671 | * slave sides may close in any order. If the slave side closes out |
| 1672 | * first, its count will be one, since the master side holds an open. |
| 1673 | * Thus this test wouldn't be triggered at the time the slave closes, |
| 1674 | * so we do it now. |
| 1675 | * |
| 1676 | * Note that it's possible for the tty to be opened again while we're |
| 1677 | * flushing out waiters. By recalculating the closing flags before |
| 1678 | * each iteration we avoid any problems. |
| 1679 | */ |
| 1680 | while (1) { |
| 1681 | /* Guard against races with tty->count changes elsewhere and |
| 1682 | opens on /dev/tty */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1683 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1684 | mutex_lock(&tty_mutex); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1685 | tty_lock_pair(tty, o_tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1686 | tty_closing = tty->count <= 1; |
| 1687 | o_tty_closing = o_tty && |
| 1688 | (o_tty->count <= (pty_master ? 1 : 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1689 | do_sleep = 0; |
| 1690 | |
| 1691 | if (tty_closing) { |
| 1692 | if (waitqueue_active(&tty->read_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1693 | wake_up_poll(&tty->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1694 | do_sleep++; |
| 1695 | } |
| 1696 | if (waitqueue_active(&tty->write_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1697 | wake_up_poll(&tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1698 | do_sleep++; |
| 1699 | } |
| 1700 | } |
| 1701 | if (o_tty_closing) { |
| 1702 | if (waitqueue_active(&o_tty->read_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1703 | wake_up_poll(&o_tty->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1704 | do_sleep++; |
| 1705 | } |
| 1706 | if (waitqueue_active(&o_tty->write_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1707 | wake_up_poll(&o_tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1708 | do_sleep++; |
| 1709 | } |
| 1710 | } |
| 1711 | if (!do_sleep) |
| 1712 | break; |
| 1713 | |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1714 | printk(KERN_WARNING "%s: %s: read/write wait queue active!\n", |
| 1715 | __func__, tty_name(tty, buf)); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1716 | tty_unlock_pair(tty, o_tty); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1717 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1718 | schedule(); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1719 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1720 | |
| 1721 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1722 | * The closing flags are now consistent with the open counts on |
| 1723 | * both sides, and we've completed the last operation that could |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1724 | * block, so it's safe to proceed with closing. |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1725 | * |
| 1726 | * We must *not* drop the tty_mutex until we ensure that a further |
| 1727 | * entry into tty_open can not pick up this tty. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1728 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1729 | if (pty_master) { |
| 1730 | if (--o_tty->count < 0) { |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1731 | printk(KERN_WARNING "%s: bad pty slave count (%d) for %s\n", |
| 1732 | __func__, o_tty->count, tty_name(o_tty, buf)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1733 | o_tty->count = 0; |
| 1734 | } |
| 1735 | } |
| 1736 | if (--tty->count < 0) { |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1737 | printk(KERN_WARNING "%s: bad tty->count (%d) for %s\n", |
| 1738 | __func__, tty->count, tty_name(tty, buf)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1739 | tty->count = 0; |
| 1740 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1741 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1742 | /* |
| 1743 | * We've decremented tty->count, so we need to remove this file |
| 1744 | * descriptor off the tty->tty_files list; this serves two |
| 1745 | * purposes: |
| 1746 | * - check_tty_count sees the correct number of file descriptors |
| 1747 | * associated with this tty. |
| 1748 | * - do_tty_hangup no longer sees this file descriptor as |
| 1749 | * something that needs to be handled for hangups. |
| 1750 | */ |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1751 | tty_del_file(filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1752 | |
| 1753 | /* |
| 1754 | * Perform some housekeeping before deciding whether to return. |
| 1755 | * |
| 1756 | * Set the TTY_CLOSING flag if this was the last open. In the |
| 1757 | * case of a pty we may have to wait around for the other side |
| 1758 | * to close, and TTY_CLOSING makes sure we can't be reopened. |
| 1759 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1760 | if (tty_closing) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1761 | set_bit(TTY_CLOSING, &tty->flags); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1762 | if (o_tty_closing) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1763 | set_bit(TTY_CLOSING, &o_tty->flags); |
| 1764 | |
| 1765 | /* |
| 1766 | * If _either_ side is closing, make sure there aren't any |
| 1767 | * processes that still think tty or o_tty is their controlling |
| 1768 | * tty. |
| 1769 | */ |
| 1770 | if (tty_closing || o_tty_closing) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1771 | read_lock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1772 | session_clear_tty(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1773 | if (o_tty) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1774 | session_clear_tty(o_tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1775 | read_unlock(&tasklist_lock); |
| 1776 | } |
| 1777 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1778 | mutex_unlock(&tty_mutex); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1779 | tty_unlock_pair(tty, o_tty); |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1780 | /* At this point the TTY_CLOSING flag should ensure a dead tty |
| 1781 | cannot be re-opened by a racing opener */ |
Paul Fulghum | da96582 | 2006-02-14 13:53:00 -0800 | [diff] [blame] | 1782 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1783 | /* check whether both sides are closing ... */ |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1784 | if (!tty_closing || (o_tty && !o_tty_closing)) |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1785 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1786 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1787 | #ifdef TTY_DEBUG_HANGUP |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1788 | printk(KERN_DEBUG "%s: freeing tty structure...\n", __func__); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1789 | #endif |
| 1790 | /* |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1791 | * Ask the line discipline code to release its structures |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1792 | */ |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1793 | tty_ldisc_release(tty, o_tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1794 | /* |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1795 | * The release_tty function takes care of the details of clearing |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1796 | * the slots and preserving the termios structure. The tty_unlock_pair |
| 1797 | * should be safe as we keep a kref while the tty is locked (so the |
| 1798 | * unlock never unlocks a freed tty). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1799 | */ |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1800 | mutex_lock(&tty_mutex); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1801 | release_tty(tty, idx); |
Alan Cox | d155255 | 2012-07-27 18:02:54 +0100 | [diff] [blame] | 1802 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1803 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1804 | /* Make this pty number available for reallocation */ |
Sukadev Bhattiprolu | 718a916 | 2008-04-30 00:54:21 -0700 | [diff] [blame] | 1805 | if (devpts) |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1806 | devpts_kill_index(inode, idx); |
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 | } |
| 1809 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1810 | /** |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1811 | * tty_open_current_tty - get tty of current task for open |
| 1812 | * @device: device number |
| 1813 | * @filp: file pointer to tty |
| 1814 | * @return: tty of the current task iff @device is /dev/tty |
| 1815 | * |
| 1816 | * We cannot return driver and index like for the other nodes because |
| 1817 | * devpts will not work then. It expects inodes to be from devpts FS. |
Alan Cox | 3af502b | 2012-05-03 22:21:53 +0100 | [diff] [blame] | 1818 | * |
| 1819 | * We need to move to returning a refcounted object from all the lookup |
| 1820 | * paths including this one. |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1821 | */ |
| 1822 | static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) |
| 1823 | { |
| 1824 | struct tty_struct *tty; |
| 1825 | |
| 1826 | if (device != MKDEV(TTYAUX_MAJOR, 0)) |
| 1827 | return NULL; |
| 1828 | |
| 1829 | tty = get_current_tty(); |
| 1830 | if (!tty) |
| 1831 | return ERR_PTR(-ENXIO); |
| 1832 | |
| 1833 | filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ |
| 1834 | /* noctty = 1; */ |
| 1835 | tty_kref_put(tty); |
| 1836 | /* FIXME: we put a reference and return a TTY! */ |
Alan Cox | 3af502b | 2012-05-03 22:21:53 +0100 | [diff] [blame] | 1837 | /* This is only safe because the caller holds tty_mutex */ |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1838 | return tty; |
| 1839 | } |
| 1840 | |
| 1841 | /** |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1842 | * tty_lookup_driver - lookup a tty driver for a given device file |
| 1843 | * @device: device number |
| 1844 | * @filp: file pointer to tty |
| 1845 | * @noctty: set if the device should not become a controlling tty |
| 1846 | * @index: index for the device in the @return driver |
| 1847 | * @return: driver for this inode (with increased refcount) |
| 1848 | * |
| 1849 | * If @return is not erroneous, the caller is responsible to decrement the |
| 1850 | * refcount by tty_driver_kref_put. |
| 1851 | * |
| 1852 | * Locking: tty_mutex protects get_tty_driver |
| 1853 | */ |
| 1854 | static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp, |
| 1855 | int *noctty, int *index) |
| 1856 | { |
| 1857 | struct tty_driver *driver; |
| 1858 | |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1859 | switch (device) { |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1860 | #ifdef CONFIG_VT |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1861 | case MKDEV(TTY_MAJOR, 0): { |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1862 | extern struct tty_driver *console_driver; |
| 1863 | driver = tty_driver_kref_get(console_driver); |
| 1864 | *index = fg_console; |
| 1865 | *noctty = 1; |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1866 | break; |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1867 | } |
| 1868 | #endif |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1869 | case MKDEV(TTYAUX_MAJOR, 1): { |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1870 | struct tty_driver *console_driver = console_device(index); |
| 1871 | if (console_driver) { |
| 1872 | driver = tty_driver_kref_get(console_driver); |
| 1873 | if (driver) { |
| 1874 | /* Don't let /dev/console block */ |
| 1875 | filp->f_flags |= O_NONBLOCK; |
| 1876 | *noctty = 1; |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1877 | break; |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1878 | } |
| 1879 | } |
| 1880 | return ERR_PTR(-ENODEV); |
| 1881 | } |
Jiri Slaby | 2cd0050 | 2011-11-09 21:33:22 +0100 | [diff] [blame] | 1882 | default: |
| 1883 | driver = get_tty_driver(device, index); |
| 1884 | if (!driver) |
| 1885 | return ERR_PTR(-ENODEV); |
| 1886 | break; |
| 1887 | } |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1888 | return driver; |
| 1889 | } |
| 1890 | |
| 1891 | /** |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1892 | * tty_open - open a tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1893 | * @inode: inode of device file |
| 1894 | * @filp: file pointer to tty |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1895 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1896 | * tty_open and tty_release keep up the tty count that contains the |
| 1897 | * number of opens done on a tty. We cannot use the inode-count, as |
| 1898 | * different inodes might point to the same tty. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1899 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1900 | * Open-counting is needed for pty masters, as well as for keeping |
| 1901 | * track of serial lines: DTR is dropped when the last close happens. |
| 1902 | * (This is not done solely through tty->count, now. - Ted 1/27/92) |
| 1903 | * |
| 1904 | * The termios state of a pty is reset on first open so that |
| 1905 | * settings don't persist across reuse. |
| 1906 | * |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1907 | * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev. |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1908 | * tty->count should protect the rest. |
| 1909 | * ->siglock protects ->signal/->sighand |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1910 | * |
| 1911 | * Note: the tty_unlock/lock cases without a ref are only safe due to |
| 1912 | * tty_mutex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1913 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1914 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1915 | static int tty_open(struct inode *inode, struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1916 | { |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1917 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1918 | int noctty, retval; |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1919 | struct tty_driver *driver = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1920 | int index; |
| 1921 | dev_t device = inode->i_rdev; |
Andrew Morton | 846c151 | 2009-04-02 16:56:36 -0700 | [diff] [blame] | 1922 | unsigned saved_flags = filp->f_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1923 | |
| 1924 | nonseekable_open(inode, filp); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1925 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1926 | retry_open: |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 1927 | retval = tty_alloc_file(filp); |
| 1928 | if (retval) |
| 1929 | return -ENOMEM; |
| 1930 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1931 | noctty = filp->f_flags & O_NOCTTY; |
| 1932 | index = -1; |
| 1933 | retval = 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1934 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1935 | mutex_lock(&tty_mutex); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1936 | /* This is protected by the tty_mutex */ |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1937 | tty = tty_open_current_tty(device, filp); |
| 1938 | if (IS_ERR(tty)) { |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 1939 | retval = PTR_ERR(tty); |
| 1940 | goto err_unlock; |
Jiri Slaby | 5b5e704 | 2011-11-09 21:33:20 +0100 | [diff] [blame] | 1941 | } else if (!tty) { |
| 1942 | driver = tty_lookup_driver(device, filp, &noctty, &index); |
| 1943 | if (IS_ERR(driver)) { |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 1944 | retval = PTR_ERR(driver); |
| 1945 | goto err_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1946 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1947 | |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1948 | /* check whether we're reopening an existing tty */ |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1949 | tty = tty_driver_lookup_tty(driver, inode, index); |
Eric Paris | 808ffa3 | 2009-01-27 11:50:37 +0000 | [diff] [blame] | 1950 | if (IS_ERR(tty)) { |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 1951 | retval = PTR_ERR(tty); |
| 1952 | goto err_unlock; |
Eric Paris | 808ffa3 | 2009-01-27 11:50:37 +0000 | [diff] [blame] | 1953 | } |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1954 | } |
| 1955 | |
| 1956 | if (tty) { |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1957 | tty_lock(tty); |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1958 | retval = tty_reopen(tty); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1959 | if (retval < 0) { |
| 1960 | tty_unlock(tty); |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1961 | tty = ERR_PTR(retval); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1962 | } |
| 1963 | } else /* Returns with the tty_lock held for now */ |
Konstantin Khlebnikov | 593a27c | 2012-01-05 13:04:21 +0400 | [diff] [blame] | 1964 | tty = tty_init_dev(driver, index); |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1965 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1966 | mutex_unlock(&tty_mutex); |
Jiri Slaby | b82154a | 2011-11-09 21:33:19 +0100 | [diff] [blame] | 1967 | if (driver) |
| 1968 | tty_driver_kref_put(driver); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1969 | if (IS_ERR(tty)) { |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 1970 | retval = PTR_ERR(tty); |
| 1971 | goto err_file; |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1972 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1973 | |
Jiri Slaby | fa90e1c | 2011-10-12 11:32:43 +0200 | [diff] [blame] | 1974 | tty_add_file(tty, filp); |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 1975 | |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1976 | check_tty_count(tty, __func__); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1977 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 1978 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 1979 | noctty = 1; |
| 1980 | #ifdef TTY_DEBUG_HANGUP |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1981 | printk(KERN_DEBUG "%s: opening %s...\n", __func__, tty->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1982 | #endif |
Herton Ronaldo Krzesinski | 909bc77 | 2011-03-31 15:35:31 -0300 | [diff] [blame] | 1983 | if (tty->ops->open) |
| 1984 | retval = tty->ops->open(tty, filp); |
| 1985 | else |
| 1986 | retval = -ENODEV; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1987 | filp->f_flags = saved_flags; |
| 1988 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1989 | if (!retval && test_bit(TTY_EXCLUSIVE, &tty->flags) && |
| 1990 | !capable(CAP_SYS_ADMIN)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1991 | retval = -EBUSY; |
| 1992 | |
| 1993 | if (retval) { |
| 1994 | #ifdef TTY_DEBUG_HANGUP |
Jiri Slaby | 9de44bd | 2011-11-09 21:33:24 +0100 | [diff] [blame] | 1995 | printk(KERN_DEBUG "%s: error %d in opening %s...\n", __func__, |
| 1996 | retval, tty->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1997 | #endif |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 1998 | tty_unlock(tty); /* need to call tty_release without BTM */ |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1999 | tty_release(inode, filp); |
Arnd Bergmann | 64ba3dc3 | 2010-06-01 22:53:02 +0200 | [diff] [blame] | 2000 | if (retval != -ERESTARTSYS) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2001 | return retval; |
Arnd Bergmann | 64ba3dc3 | 2010-06-01 22:53:02 +0200 | [diff] [blame] | 2002 | |
| 2003 | if (signal_pending(current)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2004 | return retval; |
Arnd Bergmann | 64ba3dc3 | 2010-06-01 22:53:02 +0200 | [diff] [blame] | 2005 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2006 | schedule(); |
| 2007 | /* |
| 2008 | * Need to reset f_op in case a hangup happened. |
| 2009 | */ |
| 2010 | if (filp->f_op == &hung_up_tty_fops) |
| 2011 | filp->f_op = &tty_fops; |
| 2012 | goto retry_open; |
| 2013 | } |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2014 | tty_unlock(tty); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 2015 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2016 | |
| 2017 | mutex_lock(&tty_mutex); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2018 | tty_lock(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2019 | spin_lock_irq(¤t->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2020 | if (!noctty && |
| 2021 | current->signal->leader && |
| 2022 | !current->signal->tty && |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2023 | tty->session == NULL) |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 2024 | __proc_set_tty(current, tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2025 | spin_unlock_irq(¤t->sighand->siglock); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2026 | tty_unlock(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2027 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2028 | return 0; |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 2029 | err_unlock: |
Jiri Slaby | ba5db44 | 2011-11-09 21:33:21 +0100 | [diff] [blame] | 2030 | mutex_unlock(&tty_mutex); |
| 2031 | /* after locks to avoid deadlock */ |
| 2032 | if (!IS_ERR_OR_NULL(driver)) |
| 2033 | tty_driver_kref_put(driver); |
| 2034 | err_file: |
| 2035 | tty_free_file(filp); |
| 2036 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2037 | } |
| 2038 | |
Jonathan Corbet | 39d95b9 | 2008-05-16 09:10:50 -0600 | [diff] [blame] | 2039 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2040 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2041 | /** |
| 2042 | * tty_poll - check tty status |
| 2043 | * @filp: file being polled |
| 2044 | * @wait: poll wait structures to update |
| 2045 | * |
| 2046 | * Call the line discipline polling method to obtain the poll |
| 2047 | * status of the device. |
| 2048 | * |
| 2049 | * Locking: locks called line discipline but ldisc poll method |
| 2050 | * may be re-entered freely by other callers. |
| 2051 | */ |
| 2052 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2053 | static unsigned int tty_poll(struct file *filp, poll_table *wait) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2054 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2055 | struct tty_struct *tty = file_tty(filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2056 | struct tty_ldisc *ld; |
| 2057 | int ret = 0; |
| 2058 | |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 2059 | if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_poll")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2060 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2061 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2062 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2063 | if (ld->ops->poll) |
| 2064 | ret = (ld->ops->poll)(tty, filp, wait); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2065 | tty_ldisc_deref(ld); |
| 2066 | return ret; |
| 2067 | } |
| 2068 | |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 2069 | static int __tty_fasync(int fd, struct file *filp, int on) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2070 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2071 | struct tty_struct *tty = file_tty(filp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2072 | unsigned long flags; |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2073 | int retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2074 | |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 2075 | if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_fasync")) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2076 | goto out; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2077 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2078 | retval = fasync_helper(fd, filp, on, &tty->fasync); |
| 2079 | if (retval <= 0) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2080 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2081 | |
| 2082 | if (on) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2083 | enum pid_type type; |
| 2084 | struct pid *pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2085 | if (!waitqueue_active(&tty->read_wait)) |
| 2086 | tty->minimum_to_wake = 1; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2087 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2088 | if (tty->pgrp) { |
| 2089 | pid = tty->pgrp; |
| 2090 | type = PIDTYPE_PGID; |
| 2091 | } else { |
| 2092 | pid = task_pid(current); |
| 2093 | type = PIDTYPE_PID; |
| 2094 | } |
Linus Torvalds | 80e1e82 | 2010-02-07 10:11:23 -0800 | [diff] [blame] | 2095 | get_pid(pid); |
Greg Kroah-Hartman | 7036251 | 2009-12-17 07:07:19 -0800 | [diff] [blame] | 2096 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 80e1e82 | 2010-02-07 10:11:23 -0800 | [diff] [blame] | 2097 | retval = __f_setown(filp, pid, type, 0); |
| 2098 | put_pid(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2099 | if (retval) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2100 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2101 | } else { |
| 2102 | if (!tty->fasync && !waitqueue_active(&tty->read_wait)) |
| 2103 | tty->minimum_to_wake = N_TTY_BUF_SIZE; |
| 2104 | } |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2105 | retval = 0; |
| 2106 | out: |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 2107 | return retval; |
| 2108 | } |
| 2109 | |
| 2110 | static int tty_fasync(int fd, struct file *filp, int on) |
| 2111 | { |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2112 | struct tty_struct *tty = file_tty(filp); |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 2113 | int retval; |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2114 | |
| 2115 | tty_lock(tty); |
Arnd Bergmann | ec79d60 | 2010-06-01 22:53:01 +0200 | [diff] [blame] | 2116 | retval = __tty_fasync(fd, filp, on); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2117 | tty_unlock(tty); |
| 2118 | |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 2119 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2120 | } |
| 2121 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2122 | /** |
| 2123 | * tiocsti - fake input character |
| 2124 | * @tty: tty to fake input into |
| 2125 | * @p: pointer to character |
| 2126 | * |
Robert P. J. Day | 3a4fa0a | 2007-10-19 23:10:43 +0200 | [diff] [blame] | 2127 | * Fake input to a tty device. Does the necessary locking and |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2128 | * input management. |
| 2129 | * |
| 2130 | * FIXME: does not honour flow control ?? |
| 2131 | * |
| 2132 | * Locking: |
| 2133 | * Called functions take tty_ldisc_lock |
| 2134 | * current->signal->tty check is safe without locks |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2135 | * |
| 2136 | * FIXME: may race normal receive processing |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2137 | */ |
| 2138 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2139 | static int tiocsti(struct tty_struct *tty, char __user *p) |
| 2140 | { |
| 2141 | char ch, mbz = 0; |
| 2142 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2143 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2144 | if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) |
| 2145 | return -EPERM; |
| 2146 | if (get_user(ch, p)) |
| 2147 | return -EFAULT; |
Al Viro | 1e64174 | 2008-12-09 09:23:33 +0000 | [diff] [blame] | 2148 | tty_audit_tiocsti(tty, ch); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2149 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2150 | ld->ops->receive_buf(tty, &ch, &mbz, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2151 | tty_ldisc_deref(ld); |
| 2152 | return 0; |
| 2153 | } |
| 2154 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2155 | /** |
| 2156 | * tiocgwinsz - implement window query ioctl |
| 2157 | * @tty; tty |
| 2158 | * @arg: user buffer for result |
| 2159 | * |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2160 | * Copies the kernel idea of the window size into the user buffer. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2161 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2162 | * Locking: tty->termios_mutex is taken to ensure the winsize data |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2163 | * is consistent. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2164 | */ |
| 2165 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2166 | static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2167 | { |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2168 | int err; |
| 2169 | |
Arjan van de Ven | 5785c95 | 2006-09-29 02:00:43 -0700 | [diff] [blame] | 2170 | mutex_lock(&tty->termios_mutex); |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2171 | err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); |
Arjan van de Ven | 5785c95 | 2006-09-29 02:00:43 -0700 | [diff] [blame] | 2172 | mutex_unlock(&tty->termios_mutex); |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2173 | |
| 2174 | return err ? -EFAULT: 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2175 | } |
| 2176 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2177 | /** |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2178 | * tty_do_resize - resize event |
| 2179 | * @tty: tty being resized |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2180 | * @rows: rows (character) |
| 2181 | * @cols: cols (character) |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2182 | * |
Daniel Mack | 3ad2f3f | 2010-02-03 08:01:28 +0800 | [diff] [blame] | 2183 | * Update the termios variables and send the necessary signals to |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2184 | * peform a terminal resize correctly |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2185 | */ |
| 2186 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2187 | int tty_do_resize(struct tty_struct *tty, struct winsize *ws) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2188 | { |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2189 | struct pid *pgrp; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2190 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2191 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2192 | /* Lock the tty */ |
| 2193 | mutex_lock(&tty->termios_mutex); |
| 2194 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) |
Alan Cox | ca9bda0 | 2006-09-29 02:00:03 -0700 | [diff] [blame] | 2195 | goto done; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2196 | /* Get the PID values and reference them so we can |
| 2197 | avoid holding the tty ctrl lock while sending signals */ |
| 2198 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 2199 | pgrp = get_pid(tty->pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2200 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 2201 | |
| 2202 | if (pgrp) |
| 2203 | kill_pgrp(pgrp, SIGWINCH, 1); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2204 | put_pid(pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2205 | |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2206 | tty->winsize = *ws; |
Alan Cox | ca9bda0 | 2006-09-29 02:00:03 -0700 | [diff] [blame] | 2207 | done: |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2208 | mutex_unlock(&tty->termios_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2209 | return 0; |
| 2210 | } |
| 2211 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2212 | /** |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2213 | * tiocswinsz - implement window size set ioctl |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2214 | * @tty; tty side of tty |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2215 | * @arg: user buffer for result |
| 2216 | * |
| 2217 | * Copies the user idea of the window size to the kernel. Traditionally |
| 2218 | * this is just advisory information but for the Linux console it |
| 2219 | * actually has driver level meaning and triggers a VC resize. |
| 2220 | * |
| 2221 | * Locking: |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2222 | * Driver dependent. The default do_resize method takes the |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2223 | * tty termios mutex and ctrl_lock. The console takes its own lock |
| 2224 | * then calls into the default method. |
| 2225 | */ |
| 2226 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2227 | static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2228 | { |
| 2229 | struct winsize tmp_ws; |
| 2230 | if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) |
| 2231 | return -EFAULT; |
| 2232 | |
| 2233 | if (tty->ops->resize) |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2234 | return tty->ops->resize(tty, &tmp_ws); |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2235 | else |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2236 | return tty_do_resize(tty, &tmp_ws); |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2237 | } |
| 2238 | |
| 2239 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2240 | * tioccons - allow admin to move logical console |
| 2241 | * @file: the file to become console |
| 2242 | * |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2243 | * Allow the administrator to move the redirected console device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2244 | * |
| 2245 | * Locking: uses redirect_lock to guard the redirect information |
| 2246 | */ |
| 2247 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2248 | static int tioccons(struct file *file) |
| 2249 | { |
| 2250 | if (!capable(CAP_SYS_ADMIN)) |
| 2251 | return -EPERM; |
| 2252 | if (file->f_op->write == redirected_tty_write) { |
| 2253 | struct file *f; |
| 2254 | spin_lock(&redirect_lock); |
| 2255 | f = redirect; |
| 2256 | redirect = NULL; |
| 2257 | spin_unlock(&redirect_lock); |
| 2258 | if (f) |
| 2259 | fput(f); |
| 2260 | return 0; |
| 2261 | } |
| 2262 | spin_lock(&redirect_lock); |
| 2263 | if (redirect) { |
| 2264 | spin_unlock(&redirect_lock); |
| 2265 | return -EBUSY; |
| 2266 | } |
| 2267 | get_file(file); |
| 2268 | redirect = file; |
| 2269 | spin_unlock(&redirect_lock); |
| 2270 | return 0; |
| 2271 | } |
| 2272 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2273 | /** |
| 2274 | * fionbio - non blocking ioctl |
| 2275 | * @file: file to set blocking value |
| 2276 | * @p: user parameter |
| 2277 | * |
| 2278 | * Historical tty interfaces had a blocking control ioctl before |
| 2279 | * the generic functionality existed. This piece of history is preserved |
| 2280 | * in the expected tty API of posix OS's. |
| 2281 | * |
Alan Cox | 6146b9a | 2009-09-19 13:13:19 -0700 | [diff] [blame] | 2282 | * Locking: none, the open file handle ensures it won't go away. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2283 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2284 | |
| 2285 | static int fionbio(struct file *file, int __user *p) |
| 2286 | { |
| 2287 | int nonblock; |
| 2288 | |
| 2289 | if (get_user(nonblock, p)) |
| 2290 | return -EFAULT; |
| 2291 | |
Jonathan Corbet | db1dd4d | 2009-02-06 15:25:24 -0700 | [diff] [blame] | 2292 | spin_lock(&file->f_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2293 | if (nonblock) |
| 2294 | file->f_flags |= O_NONBLOCK; |
| 2295 | else |
| 2296 | file->f_flags &= ~O_NONBLOCK; |
Jonathan Corbet | db1dd4d | 2009-02-06 15:25:24 -0700 | [diff] [blame] | 2297 | spin_unlock(&file->f_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2298 | return 0; |
| 2299 | } |
| 2300 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2301 | /** |
| 2302 | * tiocsctty - set controlling tty |
| 2303 | * @tty: tty structure |
| 2304 | * @arg: user argument |
| 2305 | * |
| 2306 | * This ioctl is used to manage job control. It permits a session |
| 2307 | * leader to set this tty as the controlling tty for the session. |
| 2308 | * |
| 2309 | * Locking: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2310 | * Takes tty_mutex() to protect tty instance |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2311 | * Takes tasklist_lock internally to walk sessions |
| 2312 | * Takes ->siglock() when updating signal->tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2313 | */ |
| 2314 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2315 | static int tiocsctty(struct tty_struct *tty, int arg) |
| 2316 | { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2317 | int ret = 0; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2318 | if (current->signal->leader && (task_session(current) == tty->session)) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2319 | return ret; |
| 2320 | |
| 2321 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2322 | /* |
| 2323 | * The process must be a session leader and |
| 2324 | * not have a controlling tty already. |
| 2325 | */ |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2326 | if (!current->signal->leader || current->signal->tty) { |
| 2327 | ret = -EPERM; |
| 2328 | goto unlock; |
| 2329 | } |
| 2330 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2331 | if (tty->session) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2332 | /* |
| 2333 | * This tty is already the controlling |
| 2334 | * tty for another session group! |
| 2335 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2336 | if (arg == 1 && capable(CAP_SYS_ADMIN)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2337 | /* |
| 2338 | * Steal it away |
| 2339 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2340 | read_lock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2341 | session_clear_tty(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2342 | read_unlock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2343 | } else { |
| 2344 | ret = -EPERM; |
| 2345 | goto unlock; |
| 2346 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2347 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2348 | proc_set_tty(current, tty); |
| 2349 | unlock: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2350 | mutex_unlock(&tty_mutex); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2351 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2352 | } |
| 2353 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2354 | /** |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2355 | * tty_get_pgrp - return a ref counted pgrp pid |
| 2356 | * @tty: tty to read |
| 2357 | * |
| 2358 | * Returns a refcounted instance of the pid struct for the process |
| 2359 | * group controlling the tty. |
| 2360 | */ |
| 2361 | |
| 2362 | struct pid *tty_get_pgrp(struct tty_struct *tty) |
| 2363 | { |
| 2364 | unsigned long flags; |
| 2365 | struct pid *pgrp; |
| 2366 | |
| 2367 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 2368 | pgrp = get_pid(tty->pgrp); |
| 2369 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 2370 | |
| 2371 | return pgrp; |
| 2372 | } |
| 2373 | EXPORT_SYMBOL_GPL(tty_get_pgrp); |
| 2374 | |
| 2375 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2376 | * tiocgpgrp - get process group |
| 2377 | * @tty: tty passed by user |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2378 | * @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] | 2379 | * @p: returned pid |
| 2380 | * |
| 2381 | * Obtain the process group of the tty. If there is no process group |
| 2382 | * return an error. |
| 2383 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2384 | * Locking: none. Reference to current->signal->tty is safe. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2385 | */ |
| 2386 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2387 | static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2388 | { |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2389 | struct pid *pid; |
| 2390 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2391 | /* |
| 2392 | * (tty == real_tty) is a cheap way of |
| 2393 | * testing if the tty is NOT a master pty. |
| 2394 | */ |
| 2395 | if (tty == real_tty && current->signal->tty != real_tty) |
| 2396 | return -ENOTTY; |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2397 | pid = tty_get_pgrp(real_tty); |
| 2398 | ret = put_user(pid_vnr(pid), p); |
| 2399 | put_pid(pid); |
| 2400 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2401 | } |
| 2402 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2403 | /** |
| 2404 | * tiocspgrp - attempt to set process group |
| 2405 | * @tty: tty passed by user |
| 2406 | * @real_tty: tty side device matching tty passed by user |
| 2407 | * @p: pid pointer |
| 2408 | * |
| 2409 | * Set the process group of the tty to the session passed. Only |
| 2410 | * permitted where the tty session is our session. |
| 2411 | * |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2412 | * Locking: RCU, ctrl lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2413 | */ |
| 2414 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2415 | static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2416 | { |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2417 | struct pid *pgrp; |
| 2418 | pid_t pgrp_nr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2419 | int retval = tty_check_change(real_tty); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2420 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2421 | |
| 2422 | if (retval == -EIO) |
| 2423 | return -ENOTTY; |
| 2424 | if (retval) |
| 2425 | return retval; |
| 2426 | if (!current->signal->tty || |
| 2427 | (current->signal->tty != real_tty) || |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2428 | (real_tty->session != task_session(current))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2429 | return -ENOTTY; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2430 | if (get_user(pgrp_nr, p)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2431 | return -EFAULT; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2432 | if (pgrp_nr < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2433 | return -EINVAL; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2434 | rcu_read_lock(); |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 2435 | pgrp = find_vpid(pgrp_nr); |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2436 | retval = -ESRCH; |
| 2437 | if (!pgrp) |
| 2438 | goto out_unlock; |
| 2439 | retval = -EPERM; |
| 2440 | if (session_of_pgrp(pgrp) != task_session(current)) |
| 2441 | goto out_unlock; |
| 2442 | retval = 0; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2443 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2444 | put_pid(real_tty->pgrp); |
| 2445 | real_tty->pgrp = get_pid(pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2446 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2447 | out_unlock: |
| 2448 | rcu_read_unlock(); |
| 2449 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2450 | } |
| 2451 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2452 | /** |
| 2453 | * tiocgsid - get session id |
| 2454 | * @tty: tty passed by user |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2455 | * @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] | 2456 | * @p: pointer to returned session id |
| 2457 | * |
| 2458 | * Obtain the session id of the tty. If there is no session |
| 2459 | * return an error. |
| 2460 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2461 | * Locking: none. Reference to current->signal->tty is safe. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2462 | */ |
| 2463 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2464 | static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2465 | { |
| 2466 | /* |
| 2467 | * (tty == real_tty) is a cheap way of |
| 2468 | * testing if the tty is NOT a master pty. |
| 2469 | */ |
| 2470 | if (tty == real_tty && current->signal->tty != real_tty) |
| 2471 | return -ENOTTY; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2472 | if (!real_tty->session) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2473 | return -ENOTTY; |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 2474 | return put_user(pid_vnr(real_tty->session), p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2475 | } |
| 2476 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2477 | /** |
| 2478 | * tiocsetd - set line discipline |
| 2479 | * @tty: tty device |
| 2480 | * @p: pointer to user data |
| 2481 | * |
| 2482 | * Set the line discipline according to user request. |
| 2483 | * |
| 2484 | * Locking: see tty_set_ldisc, this function is just a helper |
| 2485 | */ |
| 2486 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2487 | static int tiocsetd(struct tty_struct *tty, int __user *p) |
| 2488 | { |
| 2489 | int ldisc; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2490 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2491 | |
| 2492 | if (get_user(ldisc, p)) |
| 2493 | return -EFAULT; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2494 | |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2495 | ret = tty_set_ldisc(tty, ldisc); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2496 | |
| 2497 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2498 | } |
| 2499 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2500 | /** |
| 2501 | * send_break - performed time break |
| 2502 | * @tty: device to break on |
| 2503 | * @duration: timeout in mS |
| 2504 | * |
| 2505 | * Perform a timed break on hardware that lacks its own driver level |
| 2506 | * timed break functionality. |
| 2507 | * |
| 2508 | * Locking: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2509 | * atomic_write_lock serializes |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2510 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2511 | */ |
| 2512 | |
Domen Puncer | b20f3ae | 2005-06-25 14:58:42 -0700 | [diff] [blame] | 2513 | static int send_break(struct tty_struct *tty, unsigned int duration) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2514 | { |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2515 | int retval; |
| 2516 | |
| 2517 | if (tty->ops->break_ctl == NULL) |
| 2518 | return 0; |
| 2519 | |
| 2520 | if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) |
| 2521 | retval = tty->ops->break_ctl(tty, duration); |
| 2522 | else { |
| 2523 | /* Do the work ourselves */ |
| 2524 | if (tty_write_lock(tty, 0) < 0) |
| 2525 | return -EINTR; |
| 2526 | retval = tty->ops->break_ctl(tty, -1); |
| 2527 | if (retval) |
| 2528 | goto out; |
| 2529 | if (!signal_pending(current)) |
| 2530 | msleep_interruptible(duration); |
| 2531 | retval = tty->ops->break_ctl(tty, 0); |
| 2532 | out: |
| 2533 | tty_write_unlock(tty); |
| 2534 | if (signal_pending(current)) |
| 2535 | retval = -EINTR; |
| 2536 | } |
| 2537 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2538 | } |
| 2539 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2540 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2541 | * tty_tiocmget - get modem status |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2542 | * @tty: tty device |
| 2543 | * @file: user file pointer |
| 2544 | * @p: pointer to result |
| 2545 | * |
| 2546 | * Obtain the modem status bits from the tty driver if the feature |
| 2547 | * is supported. Return -EINVAL if it is not available. |
| 2548 | * |
| 2549 | * Locking: none (up to the driver) |
| 2550 | */ |
| 2551 | |
Alan Cox | 60b33c1 | 2011-02-14 16:26:14 +0000 | [diff] [blame] | 2552 | static int tty_tiocmget(struct tty_struct *tty, int __user *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2553 | { |
| 2554 | int retval = -EINVAL; |
| 2555 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2556 | if (tty->ops->tiocmget) { |
Alan Cox | 60b33c1 | 2011-02-14 16:26:14 +0000 | [diff] [blame] | 2557 | retval = tty->ops->tiocmget(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2558 | |
| 2559 | if (retval >= 0) |
| 2560 | retval = put_user(retval, p); |
| 2561 | } |
| 2562 | return retval; |
| 2563 | } |
| 2564 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2565 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2566 | * tty_tiocmset - set modem status |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2567 | * @tty: tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2568 | * @cmd: command - clear bits, set bits or set all |
| 2569 | * @p: pointer to desired bits |
| 2570 | * |
| 2571 | * Set the modem status bits from the tty driver if the feature |
| 2572 | * is supported. Return -EINVAL if it is not available. |
| 2573 | * |
| 2574 | * Locking: none (up to the driver) |
| 2575 | */ |
| 2576 | |
Alan Cox | 20b9d17 | 2011-02-14 16:26:50 +0000 | [diff] [blame] | 2577 | static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2578 | unsigned __user *p) |
| 2579 | { |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2580 | int retval; |
| 2581 | unsigned int set, clear, val; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2582 | |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2583 | if (tty->ops->tiocmset == NULL) |
| 2584 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2585 | |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2586 | retval = get_user(val, p); |
| 2587 | if (retval) |
| 2588 | return retval; |
| 2589 | set = clear = 0; |
| 2590 | switch (cmd) { |
| 2591 | case TIOCMBIS: |
| 2592 | set = val; |
| 2593 | break; |
| 2594 | case TIOCMBIC: |
| 2595 | clear = val; |
| 2596 | break; |
| 2597 | case TIOCMSET: |
| 2598 | set = val; |
| 2599 | clear = ~val; |
| 2600 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2601 | } |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2602 | set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; |
| 2603 | clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; |
Alan Cox | 20b9d17 | 2011-02-14 16:26:50 +0000 | [diff] [blame] | 2604 | return tty->ops->tiocmset(tty, set, clear); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2605 | } |
| 2606 | |
Alan Cox | d281da7 | 2010-09-16 18:21:24 +0100 | [diff] [blame] | 2607 | static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) |
| 2608 | { |
| 2609 | int retval = -EINVAL; |
| 2610 | struct serial_icounter_struct icount; |
| 2611 | memset(&icount, 0, sizeof(icount)); |
| 2612 | if (tty->ops->get_icount) |
| 2613 | retval = tty->ops->get_icount(tty, &icount); |
| 2614 | if (retval != 0) |
| 2615 | return retval; |
| 2616 | if (copy_to_user(arg, &icount, sizeof(icount))) |
| 2617 | return -EFAULT; |
| 2618 | return 0; |
| 2619 | } |
| 2620 | |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2621 | struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) |
| 2622 | { |
| 2623 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 2624 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 2625 | tty = tty->link; |
| 2626 | return tty; |
| 2627 | } |
| 2628 | EXPORT_SYMBOL(tty_pair_get_tty); |
| 2629 | |
| 2630 | struct tty_struct *tty_pair_get_pty(struct tty_struct *tty) |
| 2631 | { |
| 2632 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 2633 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 2634 | return tty; |
| 2635 | return tty->link; |
| 2636 | } |
| 2637 | EXPORT_SYMBOL(tty_pair_get_pty); |
| 2638 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2639 | /* |
| 2640 | * Split this up, as gcc can choke on it otherwise.. |
| 2641 | */ |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2642 | long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2643 | { |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2644 | struct tty_struct *tty = file_tty(file); |
| 2645 | struct tty_struct *real_tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2646 | void __user *p = (void __user *)arg; |
| 2647 | int retval; |
| 2648 | struct tty_ldisc *ld; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2649 | struct inode *inode = file->f_dentry->d_inode; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2650 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2651 | if (tty_paranoia_check(tty, inode, "tty_ioctl")) |
| 2652 | return -EINVAL; |
| 2653 | |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2654 | real_tty = tty_pair_get_tty(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2655 | |
| 2656 | /* |
| 2657 | * Factor out some common prep work |
| 2658 | */ |
| 2659 | switch (cmd) { |
| 2660 | case TIOCSETD: |
| 2661 | case TIOCSBRK: |
| 2662 | case TIOCCBRK: |
| 2663 | case TCSBRK: |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2664 | case TCSBRKP: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2665 | retval = tty_check_change(tty); |
| 2666 | if (retval) |
| 2667 | return retval; |
| 2668 | if (cmd != TIOCCBRK) { |
| 2669 | tty_wait_until_sent(tty, 0); |
| 2670 | if (signal_pending(current)) |
| 2671 | return -EINTR; |
| 2672 | } |
| 2673 | break; |
| 2674 | } |
| 2675 | |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2676 | /* |
| 2677 | * Now do the stuff. |
| 2678 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2679 | switch (cmd) { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2680 | case TIOCSTI: |
| 2681 | return tiocsti(tty, p); |
| 2682 | case TIOCGWINSZ: |
Alan Cox | 8f52002 | 2008-10-13 10:38:46 +0100 | [diff] [blame] | 2683 | return tiocgwinsz(real_tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2684 | case TIOCSWINSZ: |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2685 | return tiocswinsz(real_tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2686 | case TIOCCONS: |
| 2687 | return real_tty != tty ? -EINVAL : tioccons(file); |
| 2688 | case FIONBIO: |
| 2689 | return fionbio(file, p); |
| 2690 | case TIOCEXCL: |
| 2691 | set_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2692 | return 0; |
| 2693 | case TIOCNXCL: |
| 2694 | clear_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2695 | return 0; |
| 2696 | case TIOCNOTTY: |
| 2697 | if (current->signal->tty != tty) |
| 2698 | return -ENOTTY; |
| 2699 | no_tty(); |
| 2700 | return 0; |
| 2701 | case TIOCSCTTY: |
| 2702 | return tiocsctty(tty, arg); |
| 2703 | case TIOCGPGRP: |
| 2704 | return tiocgpgrp(tty, real_tty, p); |
| 2705 | case TIOCSPGRP: |
| 2706 | return tiocspgrp(tty, real_tty, p); |
| 2707 | case TIOCGSID: |
| 2708 | return tiocgsid(tty, real_tty, p); |
| 2709 | case TIOCGETD: |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 2710 | return put_user(tty->ldisc->ops->num, (int __user *)p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2711 | case TIOCSETD: |
| 2712 | return tiocsetd(tty, p); |
Kay Sievers | 3c95c98 | 2011-02-17 18:39:28 +0100 | [diff] [blame] | 2713 | case TIOCVHANGUP: |
| 2714 | if (!capable(CAP_SYS_ADMIN)) |
| 2715 | return -EPERM; |
| 2716 | tty_vhangup(tty); |
| 2717 | return 0; |
Werner Fink | b7b8de0 | 2010-12-03 12:48:23 +0100 | [diff] [blame] | 2718 | case TIOCGDEV: |
| 2719 | { |
| 2720 | unsigned int ret = new_encode_dev(tty_devnum(real_tty)); |
| 2721 | return put_user(ret, (unsigned int __user *)p); |
| 2722 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2723 | /* |
| 2724 | * Break handling |
| 2725 | */ |
| 2726 | case TIOCSBRK: /* Turn break on, unconditionally */ |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2727 | if (tty->ops->break_ctl) |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2728 | return tty->ops->break_ctl(tty, -1); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2729 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2730 | case TIOCCBRK: /* Turn break off, unconditionally */ |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2731 | if (tty->ops->break_ctl) |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2732 | return tty->ops->break_ctl(tty, 0); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2733 | return 0; |
| 2734 | case TCSBRK: /* SVID version: non-zero arg --> no break */ |
| 2735 | /* non-zero arg means wait for all output data |
| 2736 | * to be sent (performed above) but don't send break. |
| 2737 | * This is used by the tcdrain() termios function. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2738 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2739 | if (!arg) |
| 2740 | return send_break(tty, 250); |
| 2741 | return 0; |
| 2742 | case TCSBRKP: /* support for POSIX tcsendbreak() */ |
| 2743 | return send_break(tty, arg ? arg*100 : 250); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2744 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2745 | case TIOCMGET: |
Alan Cox | 60b33c1 | 2011-02-14 16:26:14 +0000 | [diff] [blame] | 2746 | return tty_tiocmget(tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2747 | case TIOCMSET: |
| 2748 | case TIOCMBIC: |
| 2749 | case TIOCMBIS: |
Alan Cox | 20b9d17 | 2011-02-14 16:26:50 +0000 | [diff] [blame] | 2750 | return tty_tiocmset(tty, cmd, p); |
Alan Cox | d281da7 | 2010-09-16 18:21:24 +0100 | [diff] [blame] | 2751 | case TIOCGICOUNT: |
| 2752 | retval = tty_tiocgicount(tty, p); |
| 2753 | /* For the moment allow fall through to the old method */ |
| 2754 | if (retval != -EINVAL) |
| 2755 | return retval; |
| 2756 | break; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2757 | case TCFLSH: |
| 2758 | switch (arg) { |
| 2759 | case TCIFLUSH: |
| 2760 | case TCIOFLUSH: |
| 2761 | /* flush tty buffer and allow ldisc to process ioctl */ |
| 2762 | tty_buffer_flush(tty); |
Paul Fulghum | c5c34d4 | 2007-05-12 10:36:55 -0700 | [diff] [blame] | 2763 | break; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2764 | } |
| 2765 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2766 | } |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2767 | if (tty->ops->ioctl) { |
Alan Cox | 6caa76b | 2011-02-14 16:27:22 +0000 | [diff] [blame] | 2768 | retval = (tty->ops->ioctl)(tty, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2769 | if (retval != -ENOIOCTLCMD) |
| 2770 | return retval; |
| 2771 | } |
| 2772 | ld = tty_ldisc_ref_wait(tty); |
| 2773 | retval = -EINVAL; |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2774 | if (ld->ops->ioctl) { |
| 2775 | retval = ld->ops->ioctl(tty, file, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2776 | if (retval == -ENOIOCTLCMD) |
Wanlong Gao | bbb63c5 | 2012-08-27 15:23:12 +0800 | [diff] [blame^] | 2777 | retval = -ENOTTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2778 | } |
| 2779 | tty_ldisc_deref(ld); |
| 2780 | return retval; |
| 2781 | } |
| 2782 | |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2783 | #ifdef CONFIG_COMPAT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2784 | static long tty_compat_ioctl(struct file *file, unsigned int cmd, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2785 | unsigned long arg) |
| 2786 | { |
| 2787 | struct inode *inode = file->f_dentry->d_inode; |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2788 | struct tty_struct *tty = file_tty(file); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2789 | struct tty_ldisc *ld; |
| 2790 | int retval = -ENOIOCTLCMD; |
| 2791 | |
| 2792 | if (tty_paranoia_check(tty, inode, "tty_ioctl")) |
| 2793 | return -EINVAL; |
| 2794 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2795 | if (tty->ops->compat_ioctl) { |
Alan Cox | 6caa76b | 2011-02-14 16:27:22 +0000 | [diff] [blame] | 2796 | retval = (tty->ops->compat_ioctl)(tty, cmd, arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2797 | if (retval != -ENOIOCTLCMD) |
| 2798 | return retval; |
| 2799 | } |
| 2800 | |
| 2801 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2802 | if (ld->ops->compat_ioctl) |
| 2803 | retval = ld->ops->compat_ioctl(tty, file, cmd, arg); |
Thomas Meyer | 8193c42 | 2011-10-05 23:13:13 +0200 | [diff] [blame] | 2804 | else |
| 2805 | retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2806 | tty_ldisc_deref(ld); |
| 2807 | |
| 2808 | return retval; |
| 2809 | } |
| 2810 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2811 | |
| 2812 | /* |
| 2813 | * This implements the "Secure Attention Key" --- the idea is to |
| 2814 | * prevent trojan horses by killing all processes associated with this |
| 2815 | * tty when the user hits the "Secure Attention Key". Required for |
| 2816 | * super-paranoid applications --- see the Orange Book for more details. |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2817 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2818 | * This code could be nicer; ideally it should send a HUP, wait a few |
| 2819 | * seconds, then send a INT, and then a KILL signal. But you then |
| 2820 | * have to coordinate with the init process, since all processes associated |
| 2821 | * with the current tty must be dead before the new getty is allowed |
| 2822 | * to spawn. |
| 2823 | * |
| 2824 | * Now, if it would be correct ;-/ The current code has a nasty hole - |
| 2825 | * it doesn't catch files in flight. We may send the descriptor to ourselves |
| 2826 | * via AF_UNIX socket, close it and later fetch from socket. FIXME. |
| 2827 | * |
| 2828 | * Nasty bug: do_SAK is being called in interrupt context. This can |
| 2829 | * deadlock. We punt it up to process context. AKPM - 16Mar2001 |
| 2830 | */ |
Eric W. Biederman | 8b6312f | 2007-02-10 01:44:34 -0800 | [diff] [blame] | 2831 | void __do_SAK(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2832 | { |
| 2833 | #ifdef TTY_SOFT_SAK |
| 2834 | tty_hangup(tty); |
| 2835 | #else |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2836 | struct task_struct *g, *p; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2837 | struct pid *session; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2838 | int i; |
| 2839 | struct file *filp; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 2840 | struct fdtable *fdt; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2841 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2842 | if (!tty) |
| 2843 | return; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2844 | session = tty->session; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2845 | |
Dan Carpenter | b3f13de | 2006-12-13 00:35:09 -0800 | [diff] [blame] | 2846 | tty_ldisc_flush(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2847 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2848 | tty_driver_flush_buffer(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2849 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2850 | read_lock(&tasklist_lock); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2851 | /* Kill the entire session */ |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2852 | do_each_pid_task(session, PIDTYPE_SID, p) { |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2853 | printk(KERN_NOTICE "SAK: killed process %d" |
Oleg Nesterov | 1b0f7ff | 2009-04-02 16:58:39 -0700 | [diff] [blame] | 2854 | " (%s): task_session(p)==tty->session\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2855 | task_pid_nr(p), p->comm); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2856 | send_sig(SIGKILL, p, 1); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2857 | } while_each_pid_task(session, PIDTYPE_SID, p); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2858 | /* Now kill any processes that happen to have the |
| 2859 | * tty open. |
| 2860 | */ |
| 2861 | do_each_thread(g, p) { |
| 2862 | if (p->signal->tty == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2863 | printk(KERN_NOTICE "SAK: killed process %d" |
Oleg Nesterov | 1b0f7ff | 2009-04-02 16:58:39 -0700 | [diff] [blame] | 2864 | " (%s): task_session(p)==tty->session\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2865 | task_pid_nr(p), p->comm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2866 | send_sig(SIGKILL, p, 1); |
| 2867 | continue; |
| 2868 | } |
| 2869 | task_lock(p); |
| 2870 | if (p->files) { |
Dipankar Sarma | ca99c1d | 2006-04-18 22:21:46 -0700 | [diff] [blame] | 2871 | /* |
| 2872 | * We don't take a ref to the file, so we must |
| 2873 | * hold ->file_lock instead. |
| 2874 | */ |
| 2875 | spin_lock(&p->files->file_lock); |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 2876 | fdt = files_fdtable(p->files); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2877 | for (i = 0; i < fdt->max_fds; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2878 | filp = fcheck_files(p->files, i); |
| 2879 | if (!filp) |
| 2880 | continue; |
| 2881 | if (filp->f_op->read == tty_read && |
Nick Piggin | d996b62 | 2010-08-18 04:37:36 +1000 | [diff] [blame] | 2882 | file_tty(filp) == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2883 | printk(KERN_NOTICE "SAK: killed process %d" |
| 2884 | " (%s): fd#%d opened to the tty\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2885 | task_pid_nr(p), p->comm, i); |
Eric W. Biederman | 20ac943 | 2006-04-13 04:49:07 -0600 | [diff] [blame] | 2886 | force_sig(SIGKILL, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2887 | break; |
| 2888 | } |
| 2889 | } |
Dipankar Sarma | ca99c1d | 2006-04-18 22:21:46 -0700 | [diff] [blame] | 2890 | spin_unlock(&p->files->file_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2891 | } |
| 2892 | task_unlock(p); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2893 | } while_each_thread(g, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2894 | read_unlock(&tasklist_lock); |
| 2895 | #endif |
| 2896 | } |
| 2897 | |
Eric W. Biederman | 8b6312f | 2007-02-10 01:44:34 -0800 | [diff] [blame] | 2898 | static void do_SAK_work(struct work_struct *work) |
| 2899 | { |
| 2900 | struct tty_struct *tty = |
| 2901 | container_of(work, struct tty_struct, SAK_work); |
| 2902 | __do_SAK(tty); |
| 2903 | } |
| 2904 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2905 | /* |
| 2906 | * The tq handling here is a little racy - tty->SAK_work may already be queued. |
| 2907 | * Fortunately we don't need to worry, because if ->SAK_work is already queued, |
| 2908 | * the values which we write to it will be identical to the values which it |
| 2909 | * already has. --akpm |
| 2910 | */ |
| 2911 | void do_SAK(struct tty_struct *tty) |
| 2912 | { |
| 2913 | if (!tty) |
| 2914 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2915 | schedule_work(&tty->SAK_work); |
| 2916 | } |
| 2917 | |
| 2918 | EXPORT_SYMBOL(do_SAK); |
| 2919 | |
Dmitry Eremin-Solenikov | 30004ac | 2010-08-09 18:22:49 +0400 | [diff] [blame] | 2920 | static int dev_match_devt(struct device *dev, void *data) |
| 2921 | { |
| 2922 | dev_t *devt = data; |
| 2923 | return dev->devt == *devt; |
| 2924 | } |
| 2925 | |
| 2926 | /* Must put_device() after it's unused! */ |
| 2927 | static struct device *tty_get_device(struct tty_struct *tty) |
| 2928 | { |
| 2929 | dev_t devt = tty_devnum(tty); |
| 2930 | return class_find_device(tty_class, NULL, &devt, dev_match_devt); |
| 2931 | } |
| 2932 | |
| 2933 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2934 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2935 | * initialize_tty_struct |
| 2936 | * @tty: tty to initialize |
| 2937 | * |
| 2938 | * This subroutine initializes a tty structure that has been newly |
| 2939 | * allocated. |
| 2940 | * |
| 2941 | * Locking: none - tty in question must not be exposed at this point |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2942 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2943 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 2944 | void initialize_tty_struct(struct tty_struct *tty, |
| 2945 | struct tty_driver *driver, int idx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2946 | { |
| 2947 | memset(tty, 0, sizeof(struct tty_struct)); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 2948 | kref_init(&tty->kref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2949 | tty->magic = TTY_MAGIC; |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 2950 | tty_ldisc_init(tty); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2951 | tty->session = NULL; |
| 2952 | tty->pgrp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2953 | tty->overrun_time = jiffies; |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 2954 | tty_buffer_init(tty); |
Alan Cox | 89c8d91 | 2012-08-08 16:30:13 +0100 | [diff] [blame] | 2955 | mutex_init(&tty->legacy_mutex); |
Arjan van de Ven | 5785c95 | 2006-09-29 02:00:43 -0700 | [diff] [blame] | 2956 | mutex_init(&tty->termios_mutex); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 2957 | mutex_init(&tty->ldisc_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2958 | init_waitqueue_head(&tty->write_wait); |
| 2959 | init_waitqueue_head(&tty->read_wait); |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 2960 | INIT_WORK(&tty->hangup_work, do_tty_hangup); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 2961 | mutex_init(&tty->atomic_read_lock); |
| 2962 | mutex_init(&tty->atomic_write_lock); |
Joe Peterson | a88a69c | 2009-01-02 13:40:53 +0000 | [diff] [blame] | 2963 | mutex_init(&tty->output_lock); |
| 2964 | mutex_init(&tty->echo_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2965 | spin_lock_init(&tty->read_lock); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2966 | spin_lock_init(&tty->ctrl_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2967 | INIT_LIST_HEAD(&tty->tty_files); |
Eric W. Biederman | 7f1f86a | 2007-02-13 14:38:58 -0700 | [diff] [blame] | 2968 | INIT_WORK(&tty->SAK_work, do_SAK_work); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 2969 | |
| 2970 | tty->driver = driver; |
| 2971 | tty->ops = driver->ops; |
| 2972 | tty->index = idx; |
| 2973 | tty_line_name(driver, idx, tty->name); |
Dmitry Eremin-Solenikov | 30004ac | 2010-08-09 18:22:49 +0400 | [diff] [blame] | 2974 | tty->dev = tty_get_device(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2975 | } |
| 2976 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2977 | /** |
Jiri Slaby | 6716671 | 2011-03-23 10:48:35 +0100 | [diff] [blame] | 2978 | * deinitialize_tty_struct |
| 2979 | * @tty: tty to deinitialize |
| 2980 | * |
| 2981 | * This subroutine deinitializes a tty structure that has been newly |
| 2982 | * allocated but tty_release cannot be called on that yet. |
| 2983 | * |
| 2984 | * Locking: none - tty in question must not be exposed at this point |
| 2985 | */ |
| 2986 | void deinitialize_tty_struct(struct tty_struct *tty) |
| 2987 | { |
| 2988 | tty_ldisc_deinit(tty); |
| 2989 | } |
| 2990 | |
| 2991 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2992 | * tty_put_char - write one character to a tty |
| 2993 | * @tty: tty |
| 2994 | * @ch: character |
| 2995 | * |
| 2996 | * Write one byte to the tty using the provided put_char method |
| 2997 | * if present. Returns the number of characters successfully output. |
| 2998 | * |
| 2999 | * Note: the specific put_char operation in the driver layer may go |
| 3000 | * away soon. Don't call it directly, use this method |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3001 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3002 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3003 | int tty_put_char(struct tty_struct *tty, unsigned char ch) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3004 | { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3005 | if (tty->ops->put_char) |
| 3006 | return tty->ops->put_char(tty, ch); |
| 3007 | return tty->ops->write(tty, &ch, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3008 | } |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3009 | EXPORT_SYMBOL_GPL(tty_put_char); |
| 3010 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3011 | struct class *tty_class; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3012 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3013 | static int tty_cdev_add(struct tty_driver *driver, dev_t dev, |
| 3014 | unsigned int index, unsigned int count) |
| 3015 | { |
| 3016 | /* init here, since reused cdevs cause crashes */ |
| 3017 | cdev_init(&driver->cdevs[index], &tty_fops); |
| 3018 | driver->cdevs[index].owner = driver->owner; |
| 3019 | return cdev_add(&driver->cdevs[index], dev, count); |
| 3020 | } |
| 3021 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3022 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3023 | * tty_register_device - register a tty device |
| 3024 | * @driver: the tty driver that describes the tty device |
| 3025 | * @index: the index in the tty driver for this tty device |
| 3026 | * @device: a struct device that is associated with this tty device. |
| 3027 | * This field is optional, if there is no known struct device |
| 3028 | * for this tty device it can be set to NULL safely. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3029 | * |
Greg Kroah-Hartman | 01107d3 | 2006-08-07 22:19:37 -0700 | [diff] [blame] | 3030 | * Returns a pointer to the struct device for this tty device |
| 3031 | * (or ERR_PTR(-EFOO) on error). |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 3032 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3033 | * This call is required to be made to register an individual tty device |
| 3034 | * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If |
| 3035 | * that bit is not set, this function should not be called by a tty |
| 3036 | * driver. |
| 3037 | * |
| 3038 | * Locking: ?? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3039 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3040 | |
Greg Kroah-Hartman | 01107d3 | 2006-08-07 22:19:37 -0700 | [diff] [blame] | 3041 | struct device *tty_register_device(struct tty_driver *driver, unsigned index, |
| 3042 | struct device *device) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3043 | { |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3044 | struct device *ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3045 | char name[64]; |
| 3046 | dev_t dev = MKDEV(driver->major, driver->minor_start) + index; |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3047 | bool cdev = false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3048 | |
| 3049 | if (index >= driver->num) { |
| 3050 | printk(KERN_ERR "Attempt to register invalid tty line number " |
| 3051 | " (%d).\n", index); |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 3052 | return ERR_PTR(-EINVAL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3053 | } |
| 3054 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3055 | if (driver->type == TTY_DRIVER_TYPE_PTY) |
| 3056 | pty_line_name(driver, index, name); |
| 3057 | else |
| 3058 | tty_line_name(driver, index, name); |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 3059 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3060 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) { |
| 3061 | int error = tty_cdev_add(driver, dev, index, 1); |
| 3062 | if (error) |
| 3063 | return ERR_PTR(error); |
| 3064 | cdev = true; |
| 3065 | } |
| 3066 | |
| 3067 | ret = device_create(tty_class, device, dev, NULL, name); |
| 3068 | if (IS_ERR(ret) && cdev) |
| 3069 | cdev_del(&driver->cdevs[index]); |
| 3070 | |
| 3071 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3072 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3073 | EXPORT_SYMBOL(tty_register_device); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3074 | |
| 3075 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3076 | * tty_unregister_device - unregister a tty device |
| 3077 | * @driver: the tty driver that describes the tty device |
| 3078 | * @index: the index in the tty driver for this tty device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3079 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3080 | * If a tty device is registered with a call to tty_register_device() then |
| 3081 | * this function must be called when the tty device is gone. |
| 3082 | * |
| 3083 | * Locking: ?? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3084 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 3085 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3086 | void tty_unregister_device(struct tty_driver *driver, unsigned index) |
| 3087 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3088 | device_destroy(tty_class, |
| 3089 | MKDEV(driver->major, driver->minor_start) + index); |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3090 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) |
| 3091 | cdev_del(&driver->cdevs[index]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3092 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3093 | EXPORT_SYMBOL(tty_unregister_device); |
| 3094 | |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3095 | /** |
| 3096 | * __tty_alloc_driver -- allocate tty driver |
| 3097 | * @lines: count of lines this driver can handle at most |
| 3098 | * @owner: module which is repsonsible for this driver |
| 3099 | * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags |
| 3100 | * |
| 3101 | * This should not be called directly, some of the provided macros should be |
| 3102 | * used instead. Use IS_ERR and friends on @retval. |
| 3103 | */ |
| 3104 | struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner, |
| 3105 | unsigned long flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3106 | { |
| 3107 | struct tty_driver *driver; |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3108 | unsigned int cdevs = 1; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3109 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3110 | |
Jiri Slaby | 0019b40 | 2012-08-08 22:26:43 +0200 | [diff] [blame] | 3111 | if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1)) |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3112 | return ERR_PTR(-EINVAL); |
| 3113 | |
Jean Delvare | 506eb99 | 2007-07-15 23:40:14 -0700 | [diff] [blame] | 3114 | driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3115 | if (!driver) |
| 3116 | return ERR_PTR(-ENOMEM); |
| 3117 | |
| 3118 | kref_init(&driver->kref); |
| 3119 | driver->magic = TTY_DRIVER_MAGIC; |
| 3120 | driver->num = lines; |
| 3121 | driver->owner = owner; |
| 3122 | driver->flags = flags; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3123 | |
| 3124 | if (!(flags & TTY_DRIVER_DEVPTS_MEM)) { |
| 3125 | driver->ttys = kcalloc(lines, sizeof(*driver->ttys), |
| 3126 | GFP_KERNEL); |
| 3127 | driver->termios = kcalloc(lines, sizeof(*driver->termios), |
| 3128 | GFP_KERNEL); |
| 3129 | if (!driver->ttys || !driver->termios) { |
| 3130 | err = -ENOMEM; |
| 3131 | goto err_free_all; |
| 3132 | } |
| 3133 | } |
| 3134 | |
| 3135 | if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) { |
| 3136 | driver->ports = kcalloc(lines, sizeof(*driver->ports), |
| 3137 | GFP_KERNEL); |
| 3138 | if (!driver->ports) { |
| 3139 | err = -ENOMEM; |
| 3140 | goto err_free_all; |
| 3141 | } |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3142 | cdevs = lines; |
| 3143 | } |
| 3144 | |
| 3145 | driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL); |
| 3146 | if (!driver->cdevs) { |
| 3147 | err = -ENOMEM; |
| 3148 | goto err_free_all; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3149 | } |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3150 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3151 | return driver; |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3152 | err_free_all: |
| 3153 | kfree(driver->ports); |
| 3154 | kfree(driver->ttys); |
| 3155 | kfree(driver->termios); |
| 3156 | kfree(driver); |
| 3157 | return ERR_PTR(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3158 | } |
Jiri Slaby | 7f0bc6a | 2012-08-07 21:47:42 +0200 | [diff] [blame] | 3159 | EXPORT_SYMBOL(__tty_alloc_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3160 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3161 | static void destruct_tty_driver(struct kref *kref) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3162 | { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3163 | struct tty_driver *driver = container_of(kref, struct tty_driver, kref); |
| 3164 | int i; |
| 3165 | struct ktermios *tp; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3166 | |
| 3167 | if (driver->flags & TTY_DRIVER_INSTALLED) { |
| 3168 | /* |
| 3169 | * Free the termios and termios_locked structures because |
| 3170 | * we don't want to get memory leaks when modular tty |
| 3171 | * drivers are removed from the kernel. |
| 3172 | */ |
| 3173 | for (i = 0; i < driver->num; i++) { |
| 3174 | tp = driver->termios[i]; |
| 3175 | if (tp) { |
| 3176 | driver->termios[i] = NULL; |
| 3177 | kfree(tp); |
| 3178 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3179 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) |
| 3180 | tty_unregister_device(driver, i); |
| 3181 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3182 | proc_tty_unregister_driver(driver); |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3183 | if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) |
| 3184 | cdev_del(&driver->cdevs[0]); |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3185 | } |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3186 | kfree(driver->cdevs); |
Jiri Slaby | 04831dc | 2012-06-04 13:35:36 +0200 | [diff] [blame] | 3187 | kfree(driver->ports); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3188 | kfree(driver->termios); |
| 3189 | kfree(driver->ttys); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3190 | kfree(driver); |
| 3191 | } |
| 3192 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3193 | void tty_driver_kref_put(struct tty_driver *driver) |
| 3194 | { |
| 3195 | kref_put(&driver->kref, destruct_tty_driver); |
| 3196 | } |
| 3197 | EXPORT_SYMBOL(tty_driver_kref_put); |
| 3198 | |
Jeff Dike | b68e31d | 2006-10-02 02:17:18 -0700 | [diff] [blame] | 3199 | void tty_set_operations(struct tty_driver *driver, |
| 3200 | const struct tty_operations *op) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3201 | { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 3202 | driver->ops = op; |
| 3203 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3204 | EXPORT_SYMBOL(tty_set_operations); |
| 3205 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3206 | void put_tty_driver(struct tty_driver *d) |
| 3207 | { |
| 3208 | tty_driver_kref_put(d); |
| 3209 | } |
| 3210 | EXPORT_SYMBOL(put_tty_driver); |
| 3211 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3212 | /* |
| 3213 | * Called by a tty driver to register itself. |
| 3214 | */ |
| 3215 | int tty_register_driver(struct tty_driver *driver) |
| 3216 | { |
| 3217 | int error; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3218 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3219 | dev_t dev; |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3220 | struct device *d; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3221 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3222 | if (!driver->major) { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3223 | error = alloc_chrdev_region(&dev, driver->minor_start, |
| 3224 | driver->num, driver->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3225 | if (!error) { |
| 3226 | driver->major = MAJOR(dev); |
| 3227 | driver->minor_start = MINOR(dev); |
| 3228 | } |
| 3229 | } else { |
| 3230 | dev = MKDEV(driver->major, driver->minor_start); |
Geert Uytterhoeven | e5717c4 | 2007-02-20 15:45:21 +0100 | [diff] [blame] | 3231 | error = register_chrdev_region(dev, driver->num, driver->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3232 | } |
Jiri Slaby | 9bb8a3d | 2012-06-04 13:35:35 +0200 | [diff] [blame] | 3233 | if (error < 0) |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3234 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3235 | |
Jiri Slaby | 7e73eca | 2012-08-08 22:26:44 +0200 | [diff] [blame] | 3236 | if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) { |
| 3237 | error = tty_cdev_add(driver, dev, 0, driver->num); |
| 3238 | if (error) |
| 3239 | goto err_unreg_char; |
| 3240 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3241 | |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3242 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3243 | list_add(&driver->tty_drivers, &tty_drivers); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3244 | mutex_unlock(&tty_mutex); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3245 | |
| 3246 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3247 | for (i = 0; i < driver->num; i++) { |
| 3248 | d = tty_register_device(driver, i, NULL); |
| 3249 | if (IS_ERR(d)) { |
| 3250 | error = PTR_ERR(d); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3251 | goto err_unreg_devs; |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3252 | } |
| 3253 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3254 | } |
| 3255 | proc_tty_register_driver(driver); |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3256 | driver->flags |= TTY_DRIVER_INSTALLED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3257 | return 0; |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3258 | |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3259 | err_unreg_devs: |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3260 | for (i--; i >= 0; i--) |
| 3261 | tty_unregister_device(driver, i); |
| 3262 | |
| 3263 | mutex_lock(&tty_mutex); |
| 3264 | list_del(&driver->tty_drivers); |
| 3265 | mutex_unlock(&tty_mutex); |
| 3266 | |
Jiri Slaby | 9bb8a3d | 2012-06-04 13:35:35 +0200 | [diff] [blame] | 3267 | err_unreg_char: |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3268 | unregister_chrdev_region(dev, driver->num); |
Jiri Slaby | 16a0208 | 2012-08-08 22:26:42 +0200 | [diff] [blame] | 3269 | err: |
Vasiliy Kulikov | b670bde | 2010-09-05 22:32:22 +0400 | [diff] [blame] | 3270 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3271 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3272 | EXPORT_SYMBOL(tty_register_driver); |
| 3273 | |
| 3274 | /* |
| 3275 | * Called by a tty driver to unregister itself. |
| 3276 | */ |
| 3277 | int tty_unregister_driver(struct tty_driver *driver) |
| 3278 | { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3279 | #if 0 |
| 3280 | /* FIXME */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3281 | if (driver->refcount) |
| 3282 | return -EBUSY; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3283 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3284 | unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), |
| 3285 | driver->num); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3286 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3287 | list_del(&driver->tty_drivers); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3288 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3289 | return 0; |
| 3290 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3291 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3292 | EXPORT_SYMBOL(tty_unregister_driver); |
| 3293 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3294 | dev_t tty_devnum(struct tty_struct *tty) |
| 3295 | { |
| 3296 | return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; |
| 3297 | } |
| 3298 | EXPORT_SYMBOL(tty_devnum); |
| 3299 | |
| 3300 | void proc_clear_tty(struct task_struct *p) |
| 3301 | { |
Arjan van de Ven | 7c3b1dc | 2008-10-15 10:52:34 +0100 | [diff] [blame] | 3302 | unsigned long flags; |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3303 | struct tty_struct *tty; |
Arjan van de Ven | 7c3b1dc | 2008-10-15 10:52:34 +0100 | [diff] [blame] | 3304 | spin_lock_irqsave(&p->sighand->siglock, flags); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3305 | tty = p->signal->tty; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3306 | p->signal->tty = NULL; |
Arjan van de Ven | 7c3b1dc | 2008-10-15 10:52:34 +0100 | [diff] [blame] | 3307 | spin_unlock_irqrestore(&p->sighand->siglock, flags); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3308 | tty_kref_put(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3309 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3310 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 3311 | /* Called under the sighand lock */ |
| 3312 | |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 3313 | static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3314 | { |
| 3315 | if (tty) { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 3316 | unsigned long flags; |
| 3317 | /* We should not have a session or pgrp to put here but.... */ |
| 3318 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | d9c1e9a | 2007-03-18 12:45:44 -0600 | [diff] [blame] | 3319 | put_pid(tty->session); |
| 3320 | put_pid(tty->pgrp); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3321 | tty->pgrp = get_pid(task_pgrp(tsk)); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 3322 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 3323 | tty->session = get_pid(task_session(tsk)); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3324 | if (tsk->signal->tty) { |
| 3325 | printk(KERN_DEBUG "tty not NULL!!\n"); |
| 3326 | tty_kref_put(tsk->signal->tty); |
| 3327 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3328 | } |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 3329 | put_pid(tsk->signal->tty_old_pgrp); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3330 | tsk->signal->tty = tty_kref_get(tty); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3331 | tsk->signal->tty_old_pgrp = NULL; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3332 | } |
| 3333 | |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 3334 | static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3335 | { |
| 3336 | spin_lock_irq(&tsk->sighand->siglock); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 3337 | __proc_set_tty(tsk, tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3338 | spin_unlock_irq(&tsk->sighand->siglock); |
| 3339 | } |
| 3340 | |
| 3341 | struct tty_struct *get_current_tty(void) |
| 3342 | { |
| 3343 | struct tty_struct *tty; |
Alan Cox | 934e6eb | 2008-10-13 10:40:43 +0100 | [diff] [blame] | 3344 | unsigned long flags; |
| 3345 | |
| 3346 | spin_lock_irqsave(¤t->sighand->siglock, flags); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 3347 | tty = tty_kref_get(current->signal->tty); |
Alan Cox | 934e6eb | 2008-10-13 10:40:43 +0100 | [diff] [blame] | 3348 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3349 | return tty; |
| 3350 | } |
Heiko Carstens | a311f74 | 2006-12-13 00:33:41 -0800 | [diff] [blame] | 3351 | EXPORT_SYMBOL_GPL(get_current_tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3352 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3353 | void tty_default_fops(struct file_operations *fops) |
| 3354 | { |
| 3355 | *fops = tty_fops; |
| 3356 | } |
| 3357 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3358 | /* |
| 3359 | * Initialize the console device. This is called *early*, so |
| 3360 | * we can't necessarily depend on lots of kernel help here. |
| 3361 | * Just do some early initializations, and do the complex setup |
| 3362 | * later. |
| 3363 | */ |
| 3364 | void __init console_init(void) |
| 3365 | { |
| 3366 | initcall_t *call; |
| 3367 | |
| 3368 | /* Setup the default TTY line discipline. */ |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 3369 | tty_ldisc_begin(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3370 | |
| 3371 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3372 | * set up the console device so that later boot sequences can |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3373 | * inform about problems etc.. |
| 3374 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3375 | call = __con_initcall_start; |
| 3376 | while (call < __con_initcall_end) { |
| 3377 | (*call)(); |
| 3378 | call++; |
| 3379 | } |
| 3380 | } |
| 3381 | |
Al Viro | 2c9ede5 | 2011-07-23 20:24:48 -0400 | [diff] [blame] | 3382 | static char *tty_devnode(struct device *dev, umode_t *mode) |
Kay Sievers | e454cea | 2009-09-18 23:01:12 +0200 | [diff] [blame] | 3383 | { |
| 3384 | if (!mode) |
| 3385 | return NULL; |
| 3386 | if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || |
| 3387 | dev->devt == MKDEV(TTYAUX_MAJOR, 2)) |
| 3388 | *mode = 0666; |
| 3389 | return NULL; |
| 3390 | } |
| 3391 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3392 | static int __init tty_class_init(void) |
| 3393 | { |
gregkh@suse.de | 7fe845d | 2005-03-15 14:23:15 -0800 | [diff] [blame] | 3394 | tty_class = class_create(THIS_MODULE, "tty"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3395 | if (IS_ERR(tty_class)) |
| 3396 | return PTR_ERR(tty_class); |
Kay Sievers | e454cea | 2009-09-18 23:01:12 +0200 | [diff] [blame] | 3397 | tty_class->devnode = tty_devnode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3398 | return 0; |
| 3399 | } |
| 3400 | |
| 3401 | postcore_initcall(tty_class_init); |
| 3402 | |
| 3403 | /* 3/2004 jmc: why do these devices exist? */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3404 | static struct cdev tty_cdev, console_cdev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3405 | |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3406 | static ssize_t show_cons_active(struct device *dev, |
| 3407 | struct device_attribute *attr, char *buf) |
| 3408 | { |
| 3409 | struct console *cs[16]; |
| 3410 | int i = 0; |
| 3411 | struct console *c; |
| 3412 | ssize_t count = 0; |
| 3413 | |
Torben Hohn | ac751ef | 2011-01-25 15:07:35 -0800 | [diff] [blame] | 3414 | console_lock(); |
Kay Sievers | a2a6a82 | 2011-01-09 16:39:14 +0100 | [diff] [blame] | 3415 | for_each_console(c) { |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3416 | if (!c->device) |
| 3417 | continue; |
| 3418 | if (!c->write) |
| 3419 | continue; |
| 3420 | if ((c->flags & CON_ENABLED) == 0) |
| 3421 | continue; |
| 3422 | cs[i++] = c; |
| 3423 | if (i >= ARRAY_SIZE(cs)) |
| 3424 | break; |
| 3425 | } |
| 3426 | while (i--) |
| 3427 | count += sprintf(buf + count, "%s%d%c", |
| 3428 | cs[i]->name, cs[i]->index, i ? ' ':'\n'); |
Torben Hohn | ac751ef | 2011-01-25 15:07:35 -0800 | [diff] [blame] | 3429 | console_unlock(); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3430 | |
| 3431 | return count; |
| 3432 | } |
| 3433 | static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL); |
| 3434 | |
| 3435 | static struct device *consdev; |
| 3436 | |
| 3437 | void console_sysfs_notify(void) |
| 3438 | { |
| 3439 | if (consdev) |
| 3440 | sysfs_notify(&consdev->kobj, NULL, "active"); |
| 3441 | } |
| 3442 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3443 | /* |
| 3444 | * Ok, now we can initialize the rest of the tty devices and can count |
| 3445 | * on memory allocations, interrupts etc.. |
| 3446 | */ |
David Howells | 31d1d48 | 2010-08-06 16:34:43 +0100 | [diff] [blame] | 3447 | int __init tty_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3448 | { |
| 3449 | cdev_init(&tty_cdev, &tty_fops); |
| 3450 | if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || |
| 3451 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) |
| 3452 | panic("Couldn't register /dev/tty driver\n"); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3453 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3454 | |
| 3455 | cdev_init(&console_cdev, &console_fops); |
| 3456 | if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || |
| 3457 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) |
| 3458 | panic("Couldn't register /dev/console driver\n"); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3459 | consdev = device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL, |
Greg Kroah-Hartman | 47aa579 | 2008-05-21 12:52:33 -0700 | [diff] [blame] | 3460 | "console"); |
Kay Sievers | fbc92a3 | 2010-12-01 18:51:05 +0100 | [diff] [blame] | 3461 | if (IS_ERR(consdev)) |
| 3462 | consdev = NULL; |
| 3463 | else |
Kay Sievers | a2a6a82 | 2011-01-09 16:39:14 +0100 | [diff] [blame] | 3464 | WARN_ON(device_create_file(consdev, &dev_attr_active) < 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3465 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3466 | #ifdef CONFIG_VT |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3467 | vty_init(&console_fops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3468 | #endif |
| 3469 | return 0; |
| 3470 | } |
David Howells | 31d1d48 | 2010-08-06 16:34:43 +0100 | [diff] [blame] | 3471 | |