Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/drivers/char/tty_io.c |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 5 | */ |
| 6 | |
| 7 | /* |
| 8 | * 'tty_io.c' gives an orthogonal feeling to tty's, be they consoles |
| 9 | * or rs-channels. It also implements echoing, cooked mode etc. |
| 10 | * |
| 11 | * Kill-line thanks to John T Kohl, who also corrected VMIN = VTIME = 0. |
| 12 | * |
| 13 | * Modified by Theodore Ts'o, 9/14/92, to dynamically allocate the |
| 14 | * tty_struct and tty_queue structures. Previously there was an array |
| 15 | * of 256 tty_struct's which was statically allocated, and the |
| 16 | * tty_queue structures were allocated at boot time. Both are now |
| 17 | * dynamically allocated only when the tty is open. |
| 18 | * |
| 19 | * Also restructured routines so that there is more of a separation |
| 20 | * between the high-level tty routines (tty_io.c and tty_ioctl.c) and |
| 21 | * the low-level tty routines (serial.c, pty.c, console.c). This |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 22 | * makes for cleaner and more compact code. -TYT, 9/17/92 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | * |
| 24 | * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines |
| 25 | * which can be dynamically activated and de-activated by the line |
| 26 | * discipline handling modules (like SLIP). |
| 27 | * |
| 28 | * NOTE: pay no attention to the line discipline code (yet); its |
| 29 | * interface is still subject to change in this version... |
| 30 | * -- TYT, 1/31/92 |
| 31 | * |
| 32 | * Added functionality to the OPOST tty handling. No delays, but all |
| 33 | * other bits should be there. |
| 34 | * -- Nick Holloway <alfie@dcs.warwick.ac.uk>, 27th May 1993. |
| 35 | * |
| 36 | * Rewrote canonical mode and added more termios flags. |
| 37 | * -- julian@uhunix.uhcc.hawaii.edu (J. Cowley), 13Jan94 |
| 38 | * |
| 39 | * Reorganized FASYNC support so mouse code can share it. |
| 40 | * -- ctm@ardi.com, 9Sep95 |
| 41 | * |
| 42 | * New TIOCLINUX variants added. |
| 43 | * -- mj@k332.feld.cvut.cz, 19-Nov-95 |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 44 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | * Restrict vt switching via ioctl() |
| 46 | * -- grif@cs.ucr.edu, 5-Dec-95 |
| 47 | * |
| 48 | * Move console and virtual terminal code to more appropriate files, |
| 49 | * implement CONFIG_VT and generalize console device interface. |
| 50 | * -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97 |
| 51 | * |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 52 | * Rewrote tty_init_dev and tty_release_dev to eliminate races. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | * -- Bill Hawes <whawes@star.net>, June 97 |
| 54 | * |
| 55 | * Added devfs support. |
| 56 | * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 13-Jan-1998 |
| 57 | * |
| 58 | * Added support for a Unix98-style ptmx device. |
| 59 | * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998 |
| 60 | * |
| 61 | * Reduced memory usage for older ARM systems |
| 62 | * -- Russell King <rmk@arm.linux.org.uk> |
| 63 | * |
| 64 | * Move do_SAK() into process context. Less stack use in devfs functions. |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 65 | * alloc_tty_struct() always uses kmalloc() |
| 66 | * -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | */ |
| 68 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | #include <linux/types.h> |
| 70 | #include <linux/major.h> |
| 71 | #include <linux/errno.h> |
| 72 | #include <linux/signal.h> |
| 73 | #include <linux/fcntl.h> |
| 74 | #include <linux/sched.h> |
| 75 | #include <linux/interrupt.h> |
| 76 | #include <linux/tty.h> |
| 77 | #include <linux/tty_driver.h> |
| 78 | #include <linux/tty_flip.h> |
| 79 | #include <linux/devpts_fs.h> |
| 80 | #include <linux/file.h> |
Al Viro | 9f3acc3 | 2008-04-24 07:44:08 -0400 | [diff] [blame] | 81 | #include <linux/fdtable.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | #include <linux/console.h> |
| 83 | #include <linux/timer.h> |
| 84 | #include <linux/ctype.h> |
| 85 | #include <linux/kd.h> |
| 86 | #include <linux/mm.h> |
| 87 | #include <linux/string.h> |
| 88 | #include <linux/slab.h> |
| 89 | #include <linux/poll.h> |
| 90 | #include <linux/proc_fs.h> |
| 91 | #include <linux/init.h> |
| 92 | #include <linux/module.h> |
| 93 | #include <linux/smp_lock.h> |
| 94 | #include <linux/device.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | #include <linux/wait.h> |
| 96 | #include <linux/bitops.h> |
Domen Puncer | b20f3ae | 2005-06-25 14:58:42 -0700 | [diff] [blame] | 97 | #include <linux/delay.h> |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 98 | #include <linux/seq_file.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 100 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | #include <asm/system.h> |
| 102 | |
| 103 | #include <linux/kbd_kern.h> |
| 104 | #include <linux/vt_kern.h> |
| 105 | #include <linux/selection.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | |
| 107 | #include <linux/kmod.h> |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 108 | #include <linux/nsproxy.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | |
| 110 | #undef TTY_DEBUG_HANGUP |
| 111 | |
| 112 | #define TTY_PARANOIA_CHECK 1 |
| 113 | #define CHECK_TTY_COUNT 1 |
| 114 | |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 115 | struct ktermios tty_std_termios = { /* for the benefit of tty drivers */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | .c_iflag = ICRNL | IXON, |
| 117 | .c_oflag = OPOST | ONLCR, |
| 118 | .c_cflag = B38400 | CS8 | CREAD | HUPCL, |
| 119 | .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | |
| 120 | ECHOCTL | ECHOKE | IEXTEN, |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 121 | .c_cc = INIT_C_CC, |
| 122 | .c_ispeed = 38400, |
| 123 | .c_ospeed = 38400 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | }; |
| 125 | |
| 126 | EXPORT_SYMBOL(tty_std_termios); |
| 127 | |
| 128 | /* This list gets poked at by procfs and various bits of boot up code. This |
| 129 | could do with some rationalisation such as pulling the tty proc function |
| 130 | into this file */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 131 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | LIST_HEAD(tty_drivers); /* linked list of tty drivers */ |
| 133 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 134 | /* Mutex to protect creating and releasing a tty. This is shared with |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | vt.c for deeply disgusting hack reasons */ |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 136 | DEFINE_MUTEX(tty_mutex); |
Alan Cox | de2a84f | 2006-09-29 02:00:57 -0700 | [diff] [blame] | 137 | EXPORT_SYMBOL(tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *); |
| 140 | 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] | 141 | ssize_t redirected_tty_write(struct file *, const char __user *, |
| 142 | size_t, loff_t *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | static unsigned int tty_poll(struct file *, poll_table *); |
| 144 | static int tty_open(struct inode *, struct file *); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 145 | long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 146 | #ifdef CONFIG_COMPAT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 147 | static long tty_compat_ioctl(struct file *file, unsigned int cmd, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 148 | unsigned long arg); |
| 149 | #else |
| 150 | #define tty_compat_ioctl NULL |
| 151 | #endif |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 152 | static int tty_fasync(int fd, struct file *filp, int on); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 153 | static void release_tty(struct tty_struct *tty, int idx); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 154 | 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] | 155 | 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] | 156 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 157 | /** |
| 158 | * alloc_tty_struct - allocate a tty object |
| 159 | * |
| 160 | * Return a new empty tty structure. The data fields have not |
| 161 | * been initialized in any way but has been zeroed |
| 162 | * |
| 163 | * Locking: none |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 164 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 166 | struct tty_struct *alloc_tty_struct(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | { |
Alan Cox | 1266b1e | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 168 | return kzalloc(sizeof(struct tty_struct), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | } |
| 170 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 171 | /** |
| 172 | * free_tty_struct - free a disused tty |
| 173 | * @tty: tty struct to free |
| 174 | * |
| 175 | * Free the write buffers, tty queue and tty memory itself. |
| 176 | * |
| 177 | * Locking: none. Must be called after tty is definitely unused |
| 178 | */ |
| 179 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 180 | void free_tty_struct(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | { |
| 182 | kfree(tty->write_buf); |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 183 | tty_buffer_free_all(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | kfree(tty); |
| 185 | } |
| 186 | |
| 187 | #define TTY_NUMBER(tty) ((tty)->index + (tty)->driver->name_base) |
| 188 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 189 | /** |
| 190 | * tty_name - return tty naming |
| 191 | * @tty: tty structure |
| 192 | * @buf: buffer for output |
| 193 | * |
| 194 | * Convert a tty structure into a name. The name reflects the kernel |
| 195 | * naming policy and if udev is in use may not reflect user space |
| 196 | * |
| 197 | * Locking: none |
| 198 | */ |
| 199 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | char *tty_name(struct tty_struct *tty, char *buf) |
| 201 | { |
| 202 | if (!tty) /* Hmm. NULL pointer. That's fun. */ |
| 203 | strcpy(buf, "NULL tty"); |
| 204 | else |
| 205 | strcpy(buf, tty->name); |
| 206 | return buf; |
| 207 | } |
| 208 | |
| 209 | EXPORT_SYMBOL(tty_name); |
| 210 | |
Andrew Morton | d769a66 | 2005-05-05 16:15:50 -0700 | [diff] [blame] | 211 | int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | const char *routine) |
| 213 | { |
| 214 | #ifdef TTY_PARANOIA_CHECK |
| 215 | if (!tty) { |
| 216 | printk(KERN_WARNING |
| 217 | "null TTY for (%d:%d) in %s\n", |
| 218 | imajor(inode), iminor(inode), routine); |
| 219 | return 1; |
| 220 | } |
| 221 | if (tty->magic != TTY_MAGIC) { |
| 222 | printk(KERN_WARNING |
| 223 | "bad magic number for tty struct (%d:%d) in %s\n", |
| 224 | imajor(inode), iminor(inode), routine); |
| 225 | return 1; |
| 226 | } |
| 227 | #endif |
| 228 | return 0; |
| 229 | } |
| 230 | |
| 231 | static int check_tty_count(struct tty_struct *tty, const char *routine) |
| 232 | { |
| 233 | #ifdef CHECK_TTY_COUNT |
| 234 | struct list_head *p; |
| 235 | int count = 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 236 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | file_list_lock(); |
| 238 | list_for_each(p, &tty->tty_files) { |
| 239 | count++; |
| 240 | } |
| 241 | file_list_unlock(); |
| 242 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 243 | tty->driver->subtype == PTY_TYPE_SLAVE && |
| 244 | tty->link && tty->link->count) |
| 245 | count++; |
| 246 | if (tty->count != count) { |
| 247 | printk(KERN_WARNING "Warning: dev (%s) tty->count(%d) " |
| 248 | "!= #fd's(%d) in %s\n", |
| 249 | tty->name, tty->count, count, routine); |
| 250 | return count; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 251 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | #endif |
| 253 | return 0; |
| 254 | } |
| 255 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 256 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 257 | * get_tty_driver - find device of a tty |
| 258 | * @dev_t: device identifier |
| 259 | * @index: returns the index of the tty |
| 260 | * |
| 261 | * This routine returns a tty driver structure, given a device number |
| 262 | * and also passes back the index number. |
| 263 | * |
| 264 | * Locking: caller must hold tty_mutex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 266 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | static struct tty_driver *get_tty_driver(dev_t device, int *index) |
| 268 | { |
| 269 | struct tty_driver *p; |
| 270 | |
| 271 | list_for_each_entry(p, &tty_drivers, tty_drivers) { |
| 272 | dev_t base = MKDEV(p->major, p->minor_start); |
| 273 | if (device < base || device >= base + p->num) |
| 274 | continue; |
| 275 | *index = device - base; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 276 | return tty_driver_kref_get(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | } |
| 278 | return NULL; |
| 279 | } |
| 280 | |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 281 | #ifdef CONFIG_CONSOLE_POLL |
| 282 | |
| 283 | /** |
| 284 | * tty_find_polling_driver - find device of a polled tty |
| 285 | * @name: name string to match |
| 286 | * @line: pointer to resulting tty line nr |
| 287 | * |
| 288 | * This routine returns a tty driver structure, given a name |
| 289 | * and the condition that the tty driver is capable of polled |
| 290 | * operation. |
| 291 | */ |
| 292 | struct tty_driver *tty_find_polling_driver(char *name, int *line) |
| 293 | { |
| 294 | struct tty_driver *p, *res = NULL; |
| 295 | int tty_line = 0; |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 296 | int len; |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 297 | char *str, *stp; |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 298 | |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 299 | for (str = name; *str; str++) |
| 300 | if ((*str >= '0' && *str <= '9') || *str == ',') |
| 301 | break; |
| 302 | if (!*str) |
| 303 | return NULL; |
| 304 | |
| 305 | len = str - name; |
| 306 | tty_line = simple_strtoul(str, &str, 10); |
| 307 | |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 308 | mutex_lock(&tty_mutex); |
| 309 | /* Search through the tty devices to look for a match */ |
| 310 | list_for_each_entry(p, &tty_drivers, tty_drivers) { |
Jason Wessel | 0dca0fd | 2008-09-26 10:36:42 -0500 | [diff] [blame] | 311 | if (strncmp(name, p->name, len) != 0) |
| 312 | continue; |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 313 | stp = str; |
| 314 | if (*stp == ',') |
| 315 | stp++; |
| 316 | if (*stp == '\0') |
| 317 | stp = NULL; |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 318 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 319 | if (tty_line >= 0 && tty_line <= p->num && p->ops && |
Alan Cox | 5f0878a | 2009-06-11 12:46:41 +0100 | [diff] [blame] | 320 | p->ops->poll_init && !p->ops->poll_init(p, tty_line, stp)) { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 321 | res = tty_driver_kref_get(p); |
Jason Wessel | f2d937f | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 322 | *line = tty_line; |
| 323 | break; |
| 324 | } |
| 325 | } |
| 326 | mutex_unlock(&tty_mutex); |
| 327 | |
| 328 | return res; |
| 329 | } |
| 330 | EXPORT_SYMBOL_GPL(tty_find_polling_driver); |
| 331 | #endif |
| 332 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 333 | /** |
| 334 | * tty_check_change - check for POSIX terminal changes |
| 335 | * @tty: tty to check |
| 336 | * |
| 337 | * If we try to write to, or set the state of, a terminal and we're |
| 338 | * not in the foreground, send a SIGTTOU. If the signal is blocked or |
| 339 | * ignored, go ahead and perform the operation. (POSIX 7.2) |
| 340 | * |
Alan Cox | 978e595 | 2008-04-30 00:53:59 -0700 | [diff] [blame] | 341 | * Locking: ctrl_lock |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 343 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 344 | int tty_check_change(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 346 | unsigned long flags; |
| 347 | int ret = 0; |
| 348 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | if (current->signal->tty != tty) |
| 350 | return 0; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 351 | |
| 352 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 353 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 354 | if (!tty->pgrp) { |
| 355 | printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n"); |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 356 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | } |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 358 | if (task_pgrp(current) == tty->pgrp) |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 359 | goto out_unlock; |
| 360 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | if (is_ignored(SIGTTOU)) |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 362 | goto out; |
| 363 | if (is_current_pgrp_orphaned()) { |
| 364 | ret = -EIO; |
| 365 | goto out; |
| 366 | } |
Oleg Nesterov | 040b636 | 2007-06-01 00:46:53 -0700 | [diff] [blame] | 367 | kill_pgrp(task_pgrp(current), SIGTTOU, 1); |
| 368 | set_thread_flag(TIF_SIGPENDING); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 369 | ret = -ERESTARTSYS; |
| 370 | out: |
Andrew Morton | 9ffee4c | 2008-05-14 16:05:58 -0700 | [diff] [blame] | 371 | return ret; |
| 372 | out_unlock: |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 373 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 374 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | } |
| 376 | |
| 377 | EXPORT_SYMBOL(tty_check_change); |
| 378 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 379 | 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] | 380 | size_t count, loff_t *ppos) |
| 381 | { |
| 382 | return 0; |
| 383 | } |
| 384 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 385 | 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] | 386 | size_t count, loff_t *ppos) |
| 387 | { |
| 388 | return -EIO; |
| 389 | } |
| 390 | |
| 391 | /* No kernel lock held - none needed ;) */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 392 | 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] | 393 | { |
| 394 | return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; |
| 395 | } |
| 396 | |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 397 | static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, |
| 398 | unsigned long arg) |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 399 | { |
| 400 | return cmd == TIOCSPGRP ? -ENOTTY : -EIO; |
| 401 | } |
| 402 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 403 | static long hung_up_tty_compat_ioctl(struct file *file, |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 404 | unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | { |
| 406 | return cmd == TIOCSPGRP ? -ENOTTY : -EIO; |
| 407 | } |
| 408 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 409 | static const struct file_operations tty_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | .llseek = no_llseek, |
| 411 | .read = tty_read, |
| 412 | .write = tty_write, |
| 413 | .poll = tty_poll, |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 414 | .unlocked_ioctl = tty_ioctl, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 415 | .compat_ioctl = tty_compat_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 416 | .open = tty_open, |
| 417 | .release = tty_release, |
| 418 | .fasync = tty_fasync, |
| 419 | }; |
| 420 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 421 | static const struct file_operations console_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | .llseek = no_llseek, |
| 423 | .read = tty_read, |
| 424 | .write = redirected_tty_write, |
| 425 | .poll = tty_poll, |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 426 | .unlocked_ioctl = tty_ioctl, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 427 | .compat_ioctl = tty_compat_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | .open = tty_open, |
| 429 | .release = tty_release, |
| 430 | .fasync = tty_fasync, |
| 431 | }; |
| 432 | |
Arjan van de Ven | 62322d2 | 2006-07-03 00:24:21 -0700 | [diff] [blame] | 433 | static const struct file_operations hung_up_tty_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | .llseek = no_llseek, |
| 435 | .read = hung_up_tty_read, |
| 436 | .write = hung_up_tty_write, |
| 437 | .poll = hung_up_tty_poll, |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 438 | .unlocked_ioctl = hung_up_tty_ioctl, |
Paul Fulghum | 38ad2ed | 2007-06-16 10:15:55 -0700 | [diff] [blame] | 439 | .compat_ioctl = hung_up_tty_compat_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | .release = tty_release, |
| 441 | }; |
| 442 | |
| 443 | static DEFINE_SPINLOCK(redirect_lock); |
| 444 | static struct file *redirect; |
| 445 | |
| 446 | /** |
| 447 | * tty_wakeup - request more data |
| 448 | * @tty: terminal |
| 449 | * |
| 450 | * Internal and external helper for wakeups of tty. This function |
| 451 | * informs the line discipline if present that the driver is ready |
| 452 | * to receive more output data. |
| 453 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 454 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | void tty_wakeup(struct tty_struct *tty) |
| 456 | { |
| 457 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 458 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) { |
| 460 | ld = tty_ldisc_ref(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 461 | if (ld) { |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 462 | if (ld->ops->write_wakeup) |
| 463 | ld->ops->write_wakeup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | tty_ldisc_deref(ld); |
| 465 | } |
| 466 | } |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 467 | wake_up_interruptible_poll(&tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | } |
| 469 | |
| 470 | EXPORT_SYMBOL_GPL(tty_wakeup); |
| 471 | |
| 472 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 473 | * do_tty_hangup - actual handler for hangup events |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 474 | * @work: tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 475 | * |
Alan Cox | 1bad879 | 2008-07-22 23:38:04 +0100 | [diff] [blame] | 476 | * This can be called by the "eventd" kernel thread. That is process |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 477 | * synchronous but doesn't hold any locks, so we need to make sure we |
| 478 | * have the appropriate locks for what we're doing. |
| 479 | * |
| 480 | * The hangup event clears any pending redirections onto the hung up |
| 481 | * device. It ensures future writes will error and it does the needed |
| 482 | * line discipline hangup and signal delivery. The tty object itself |
| 483 | * remains intact. |
| 484 | * |
| 485 | * Locking: |
| 486 | * BKL |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 487 | * redirect lock for undoing redirection |
| 488 | * file list lock for manipulating list of ttys |
| 489 | * tty_ldisc_lock from called functions |
| 490 | * termios_mutex resetting termios data |
| 491 | * tasklist_lock to walk task list for hangup event |
| 492 | * ->siglock to protect ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 493 | */ |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 494 | static void do_tty_hangup(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | { |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 496 | struct tty_struct *tty = |
| 497 | container_of(work, struct tty_struct, hangup_work); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 498 | struct file *cons_filp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | struct file *filp, *f = NULL; |
| 500 | struct task_struct *p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | int closecount = 0, n; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 502 | unsigned long flags; |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 503 | int refs = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | |
| 505 | if (!tty) |
| 506 | return; |
| 507 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | |
| 509 | spin_lock(&redirect_lock); |
| 510 | if (redirect && redirect->private_data == tty) { |
| 511 | f = redirect; |
| 512 | redirect = NULL; |
| 513 | } |
| 514 | spin_unlock(&redirect_lock); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 515 | |
Alan Cox | 38c70b2 | 2009-11-30 13:18:40 +0000 | [diff] [blame] | 516 | /* inuse_filps is protected by the single kernel lock */ |
| 517 | lock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | check_tty_count(tty, "do_tty_hangup"); |
Alan Cox | 36ba782 | 2009-11-30 13:18:51 +0000 | [diff] [blame] | 519 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | file_list_lock(); |
| 521 | /* This breaks for file handles being sent over AF_UNIX sockets ? */ |
Eric Dumazet | 2f51201 | 2005-10-30 15:02:16 -0800 | [diff] [blame] | 522 | list_for_each_entry(filp, &tty->tty_files, f_u.fu_list) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | if (filp->f_op->write == redirected_tty_write) |
| 524 | cons_filp = filp; |
| 525 | if (filp->f_op->write != tty_write) |
| 526 | continue; |
| 527 | closecount++; |
| 528 | tty_fasync(-1, filp, 0); /* can't block */ |
| 529 | filp->f_op = &hung_up_tty_fops; |
| 530 | } |
| 531 | file_list_unlock(); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 532 | |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 533 | tty_ldisc_hangup(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 534 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 535 | read_lock(&tasklist_lock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 536 | if (tty->session) { |
| 537 | do_each_pid_task(tty->session, PIDTYPE_SID, p) { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 538 | spin_lock_irq(&p->sighand->siglock); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 539 | if (p->signal->tty == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | p->signal->tty = NULL; |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 541 | /* We defer the dereferences outside fo |
| 542 | the tasklist lock */ |
| 543 | refs++; |
| 544 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 545 | if (!p->signal->leader) { |
| 546 | spin_unlock_irq(&p->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | continue; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 548 | } |
| 549 | __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); |
| 550 | __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 551 | put_pid(p->signal->tty_old_pgrp); /* A noop */ |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 552 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 553 | if (tty->pgrp) |
| 554 | p->signal->tty_old_pgrp = get_pid(tty->pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 555 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 556 | spin_unlock_irq(&p->sighand->siglock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 557 | } while_each_pid_task(tty->session, PIDTYPE_SID, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 558 | } |
| 559 | read_unlock(&tasklist_lock); |
| 560 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 561 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 562 | clear_bit(TTY_THROTTLED, &tty->flags); |
| 563 | clear_bit(TTY_PUSH, &tty->flags); |
| 564 | clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); |
Eric W. Biederman | d9c1e9a | 2007-03-18 12:45:44 -0600 | [diff] [blame] | 565 | put_pid(tty->session); |
| 566 | put_pid(tty->pgrp); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 567 | tty->session = NULL; |
| 568 | tty->pgrp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 569 | tty->ctrl_status = 0; |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 570 | set_bit(TTY_HUPPED, &tty->flags); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 571 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 572 | |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 573 | /* Account for the p->signal references we killed */ |
| 574 | while (refs--) |
| 575 | tty_kref_put(tty); |
| 576 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 578 | * If one of the devices matches a console pointer, we |
| 579 | * cannot just call hangup() because that will cause |
| 580 | * tty->count and state->count to go out of sync. |
| 581 | * So we just call close() the right number of times. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 582 | */ |
| 583 | if (cons_filp) { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 584 | if (tty->ops->close) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 585 | for (n = 0; n < closecount; n++) |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 586 | tty->ops->close(tty, cons_filp); |
| 587 | } else if (tty->ops->hangup) |
| 588 | (tty->ops->hangup)(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 589 | /* |
| 590 | * We don't want to have driver/ldisc interactions beyond |
| 591 | * the ones we did here. The driver layer expects no |
| 592 | * calls after ->hangup() from the ldisc side. However we |
| 593 | * can't yet guarantee all that. |
| 594 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 595 | set_bit(TTY_HUPPED, &tty->flags); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 596 | tty_ldisc_enable(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | unlock_kernel(); |
| 598 | if (f) |
| 599 | fput(f); |
| 600 | } |
| 601 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 602 | /** |
| 603 | * tty_hangup - trigger a hangup event |
| 604 | * @tty: tty to hangup |
| 605 | * |
| 606 | * A carrier loss (virtual or otherwise) has occurred on this like |
| 607 | * schedule a hangup sequence to run after this event. |
| 608 | */ |
| 609 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 610 | void tty_hangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | { |
| 612 | #ifdef TTY_DEBUG_HANGUP |
| 613 | char buf[64]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | printk(KERN_DEBUG "%s hangup...\n", tty_name(tty, buf)); |
| 615 | #endif |
| 616 | schedule_work(&tty->hangup_work); |
| 617 | } |
| 618 | |
| 619 | EXPORT_SYMBOL(tty_hangup); |
| 620 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 621 | /** |
| 622 | * tty_vhangup - process vhangup |
| 623 | * @tty: tty to hangup |
| 624 | * |
| 625 | * The user has asked via system call for the terminal to be hung up. |
| 626 | * 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] | 627 | * is complete. That guarantee is necessary for security reasons. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 628 | */ |
| 629 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 630 | void tty_vhangup(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | { |
| 632 | #ifdef TTY_DEBUG_HANGUP |
| 633 | char buf[64]; |
| 634 | |
| 635 | printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty, buf)); |
| 636 | #endif |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 637 | do_tty_hangup(&tty->hangup_work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 639 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | EXPORT_SYMBOL(tty_vhangup); |
| 641 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 642 | /** |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 643 | * tty_vhangup_self - process vhangup for own ctty |
| 644 | * |
| 645 | * Perform a vhangup on the current controlling tty |
| 646 | */ |
| 647 | |
| 648 | void tty_vhangup_self(void) |
| 649 | { |
| 650 | struct tty_struct *tty; |
| 651 | |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 652 | tty = get_current_tty(); |
| 653 | if (tty) { |
| 654 | tty_vhangup(tty); |
| 655 | tty_kref_put(tty); |
| 656 | } |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 657 | } |
| 658 | |
| 659 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 660 | * tty_hung_up_p - was tty hung up |
| 661 | * @filp: file pointer of tty |
| 662 | * |
| 663 | * Return true if the tty has been subject to a vhangup or a carrier |
| 664 | * loss |
| 665 | */ |
| 666 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 667 | int tty_hung_up_p(struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | { |
| 669 | return (filp->f_op == &hung_up_tty_fops); |
| 670 | } |
| 671 | |
| 672 | EXPORT_SYMBOL(tty_hung_up_p); |
| 673 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 674 | static void session_clear_tty(struct pid *session) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 675 | { |
| 676 | struct task_struct *p; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 677 | do_each_pid_task(session, PIDTYPE_SID, p) { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 678 | proc_clear_tty(p); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 679 | } while_each_pid_task(session, PIDTYPE_SID, p); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 680 | } |
| 681 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 682 | /** |
| 683 | * disassociate_ctty - disconnect controlling tty |
| 684 | * @on_exit: true if exiting so need to "hang up" the session |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 686 | * This function is typically called only by the session leader, when |
| 687 | * it wants to disassociate itself from its controlling tty. |
| 688 | * |
| 689 | * It performs the following functions: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 690 | * (1) Sends a SIGHUP and SIGCONT to the foreground process group |
| 691 | * (2) Clears the tty from being controlling the session |
| 692 | * (3) Clears the controlling tty for all processes in the |
| 693 | * session group. |
| 694 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 695 | * The argument on_exit is set to 1 if called when a process is |
| 696 | * exiting; it is 0 if called by the ioctl TIOCNOTTY. |
| 697 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 698 | * Locking: |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 699 | * BKL is taken for hysterical raisins |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 700 | * tty_mutex is taken to protect tty |
| 701 | * ->siglock is taken to protect ->signal/->sighand |
| 702 | * tasklist_lock is taken to walk process list for sessions |
| 703 | * ->siglock is taken to protect ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 705 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | void disassociate_ctty(int on_exit) |
| 707 | { |
| 708 | struct tty_struct *tty; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 709 | struct pid *tty_pgrp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | |
Alan Cox | 5ec93d1 | 2009-11-30 13:18:45 +0000 | [diff] [blame] | 711 | if (!current->signal->leader) |
| 712 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 714 | tty = get_current_tty(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 715 | if (tty) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 716 | tty_pgrp = get_pid(tty->pgrp); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 717 | lock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) |
| 719 | tty_vhangup(tty); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 720 | unlock_kernel(); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 721 | tty_kref_put(tty); |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 722 | } else if (on_exit) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 723 | struct pid *old_pgrp; |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 724 | spin_lock_irq(¤t->sighand->siglock); |
| 725 | old_pgrp = current->signal->tty_old_pgrp; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 726 | current->signal->tty_old_pgrp = NULL; |
Eric W. Biederman | 680a967 | 2007-02-12 00:52:52 -0800 | [diff] [blame] | 727 | spin_unlock_irq(¤t->sighand->siglock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 728 | if (old_pgrp) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 729 | kill_pgrp(old_pgrp, SIGHUP, on_exit); |
| 730 | kill_pgrp(old_pgrp, SIGCONT, on_exit); |
| 731 | put_pid(old_pgrp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | return; |
| 734 | } |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 735 | if (tty_pgrp) { |
| 736 | kill_pgrp(tty_pgrp, SIGHUP, on_exit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | if (!on_exit) |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 738 | kill_pgrp(tty_pgrp, SIGCONT, on_exit); |
| 739 | put_pid(tty_pgrp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 740 | } |
| 741 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 742 | spin_lock_irq(¤t->sighand->siglock); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 743 | put_pid(current->signal->tty_old_pgrp); |
Randy Dunlap | 23cac8d | 2007-02-20 13:58:05 -0800 | [diff] [blame] | 744 | current->signal->tty_old_pgrp = NULL; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 745 | spin_unlock_irq(¤t->sighand->siglock); |
| 746 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 747 | tty = get_current_tty(); |
| 748 | if (tty) { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 749 | unsigned long flags; |
| 750 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 751 | put_pid(tty->session); |
| 752 | put_pid(tty->pgrp); |
| 753 | tty->session = NULL; |
| 754 | tty->pgrp = NULL; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 755 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 756 | tty_kref_put(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 757 | } else { |
| 758 | #ifdef TTY_DEBUG_HANGUP |
| 759 | printk(KERN_DEBUG "error attempted to write to tty [0x%p]" |
| 760 | " = NULL", tty); |
| 761 | #endif |
| 762 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | |
| 764 | /* Now clear signal->tty under the lock */ |
| 765 | read_lock(&tasklist_lock); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 766 | session_clear_tty(task_session(current)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | read_unlock(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | } |
| 769 | |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 770 | /** |
| 771 | * |
| 772 | * no_tty - Ensure the current process does not have a controlling tty |
| 773 | */ |
| 774 | void no_tty(void) |
| 775 | { |
| 776 | struct task_struct *tsk = current; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 777 | lock_kernel(); |
Alan Cox | 5ec93d1 | 2009-11-30 13:18:45 +0000 | [diff] [blame] | 778 | disassociate_ctty(0); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 779 | unlock_kernel(); |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 780 | proc_clear_tty(tsk); |
| 781 | } |
| 782 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 783 | |
| 784 | /** |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 785 | * stop_tty - propagate flow control |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 786 | * @tty: tty to stop |
| 787 | * |
| 788 | * 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] | 789 | * must also propagate the TIOCKPKT status. May be called |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 790 | * on an already stopped device and will not re-call the driver |
| 791 | * method. |
| 792 | * |
| 793 | * This functionality is used by both the line disciplines for |
| 794 | * halting incoming flow and by the driver. It may therefore be |
| 795 | * called from any context, may be under the tty atomic_write_lock |
| 796 | * but not always. |
| 797 | * |
| 798 | * Locking: |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 799 | * Uses the tty control lock internally |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 800 | */ |
| 801 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | void stop_tty(struct tty_struct *tty) |
| 803 | { |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 804 | unsigned long flags; |
| 805 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 806 | if (tty->stopped) { |
| 807 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | return; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 809 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | tty->stopped = 1; |
| 811 | if (tty->link && tty->link->packet) { |
| 812 | tty->ctrl_status &= ~TIOCPKT_START; |
| 813 | tty->ctrl_status |= TIOCPKT_STOP; |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 814 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | } |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 816 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 817 | if (tty->ops->stop) |
| 818 | (tty->ops->stop)(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | } |
| 820 | |
| 821 | EXPORT_SYMBOL(stop_tty); |
| 822 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 823 | /** |
Robert P. J. Day | beb7dd8 | 2007-05-09 07:14:03 +0200 | [diff] [blame] | 824 | * start_tty - propagate flow control |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 825 | * @tty: tty to start |
| 826 | * |
| 827 | * 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] | 828 | * any necessary wakeups and propagate the TIOCPKT status. If this |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 829 | * is the tty was previous stopped and is being started then the |
| 830 | * driver start method is invoked and the line discipline woken. |
| 831 | * |
| 832 | * Locking: |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 833 | * ctrl_lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 834 | */ |
| 835 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 836 | void start_tty(struct tty_struct *tty) |
| 837 | { |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 838 | unsigned long flags; |
| 839 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 840 | if (!tty->stopped || tty->flow_stopped) { |
| 841 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 842 | return; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 843 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 844 | tty->stopped = 0; |
| 845 | if (tty->link && tty->link->packet) { |
| 846 | tty->ctrl_status &= ~TIOCPKT_STOP; |
| 847 | tty->ctrl_status |= TIOCPKT_START; |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 848 | wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 849 | } |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 850 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 851 | if (tty->ops->start) |
| 852 | (tty->ops->start)(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | /* If we have a running line discipline it may need kicking */ |
| 854 | tty_wakeup(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | } |
| 856 | |
| 857 | EXPORT_SYMBOL(start_tty); |
| 858 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 859 | /** |
| 860 | * tty_read - read method for tty device files |
| 861 | * @file: pointer to tty file |
| 862 | * @buf: user buffer |
| 863 | * @count: size of user buffer |
| 864 | * @ppos: unused |
| 865 | * |
| 866 | * Perform the read system call function on this terminal device. Checks |
| 867 | * for hung up devices before calling the line discipline method. |
| 868 | * |
| 869 | * Locking: |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 870 | * Locks the line discipline internally while needed. Multiple |
| 871 | * read calls may be outstanding in parallel. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 872 | */ |
| 873 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 874 | 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] | 875 | loff_t *ppos) |
| 876 | { |
| 877 | int i; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 878 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 879 | struct inode *inode; |
| 880 | struct tty_ldisc *ld; |
| 881 | |
| 882 | tty = (struct tty_struct *)file->private_data; |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 883 | inode = file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 884 | if (tty_paranoia_check(tty, inode, "tty_read")) |
| 885 | return -EIO; |
| 886 | if (!tty || (test_bit(TTY_IO_ERROR, &tty->flags))) |
| 887 | return -EIO; |
| 888 | |
| 889 | /* We want to wait for the line discipline to sort out in this |
| 890 | situation */ |
| 891 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 892 | if (ld->ops->read) |
| 893 | i = (ld->ops->read)(tty, file, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 894 | else |
| 895 | i = -EIO; |
| 896 | tty_ldisc_deref(ld); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | if (i > 0) |
| 898 | inode->i_atime = current_fs_time(inode->i_sb); |
| 899 | return i; |
| 900 | } |
| 901 | |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 902 | void tty_write_unlock(struct tty_struct *tty) |
| 903 | { |
| 904 | mutex_unlock(&tty->atomic_write_lock); |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 905 | wake_up_interruptible_poll(&tty->write_wait, POLLOUT); |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 906 | } |
| 907 | |
| 908 | int tty_write_lock(struct tty_struct *tty, int ndelay) |
| 909 | { |
| 910 | if (!mutex_trylock(&tty->atomic_write_lock)) { |
| 911 | if (ndelay) |
| 912 | return -EAGAIN; |
| 913 | if (mutex_lock_interruptible(&tty->atomic_write_lock)) |
| 914 | return -ERESTARTSYS; |
| 915 | } |
| 916 | return 0; |
| 917 | } |
| 918 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 919 | /* |
| 920 | * Split writes up in sane blocksizes to avoid |
| 921 | * denial-of-service type attacks |
| 922 | */ |
| 923 | static inline ssize_t do_tty_write( |
| 924 | ssize_t (*write)(struct tty_struct *, struct file *, const unsigned char *, size_t), |
| 925 | struct tty_struct *tty, |
| 926 | struct file *file, |
| 927 | const char __user *buf, |
| 928 | size_t count) |
| 929 | { |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 930 | ssize_t ret, written = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | unsigned int chunk; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 932 | |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 933 | ret = tty_write_lock(tty, file->f_flags & O_NDELAY); |
| 934 | if (ret < 0) |
| 935 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | |
| 937 | /* |
| 938 | * We chunk up writes into a temporary buffer. This |
| 939 | * simplifies low-level drivers immensely, since they |
| 940 | * don't have locking issues and user mode accesses. |
| 941 | * |
| 942 | * But if TTY_NO_WRITE_SPLIT is set, we should use a |
| 943 | * big chunk-size.. |
| 944 | * |
| 945 | * The default chunk-size is 2kB, because the NTTY |
| 946 | * layer has problems with bigger chunks. It will |
| 947 | * claim to be able to handle more characters than |
| 948 | * it actually does. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 949 | * |
| 950 | * FIXME: This can probably go away now except that 64K chunks |
| 951 | * are too likely to fail unless switched to vmalloc... |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 952 | */ |
| 953 | chunk = 2048; |
| 954 | if (test_bit(TTY_NO_WRITE_SPLIT, &tty->flags)) |
| 955 | chunk = 65536; |
| 956 | if (count < chunk) |
| 957 | chunk = count; |
| 958 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 959 | /* write_buf/write_cnt is protected by the atomic_write_lock mutex */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 960 | if (tty->write_cnt < chunk) { |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 961 | unsigned char *buf_chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 962 | |
| 963 | if (chunk < 1024) |
| 964 | chunk = 1024; |
| 965 | |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 966 | buf_chunk = kmalloc(chunk, GFP_KERNEL); |
| 967 | if (!buf_chunk) { |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 968 | ret = -ENOMEM; |
| 969 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 970 | } |
| 971 | kfree(tty->write_buf); |
| 972 | tty->write_cnt = chunk; |
Jason Wessel | 402fda9 | 2008-10-13 10:45:36 +0100 | [diff] [blame] | 973 | tty->write_buf = buf_chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 974 | } |
| 975 | |
| 976 | /* Do the write .. */ |
| 977 | for (;;) { |
| 978 | size_t size = count; |
| 979 | if (size > chunk) |
| 980 | size = chunk; |
| 981 | ret = -EFAULT; |
| 982 | if (copy_from_user(tty->write_buf, buf, size)) |
| 983 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 984 | ret = write(tty, file, tty->write_buf, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 985 | if (ret <= 0) |
| 986 | break; |
| 987 | written += ret; |
| 988 | buf += ret; |
| 989 | count -= ret; |
| 990 | if (!count) |
| 991 | break; |
| 992 | ret = -ERESTARTSYS; |
| 993 | if (signal_pending(current)) |
| 994 | break; |
| 995 | cond_resched(); |
| 996 | } |
| 997 | if (written) { |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 998 | struct inode *inode = file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 999 | inode->i_mtime = current_fs_time(inode->i_sb); |
| 1000 | ret = written; |
| 1001 | } |
Alan Cox | 9c1729d | 2007-07-15 23:39:43 -0700 | [diff] [blame] | 1002 | out: |
| 1003 | tty_write_unlock(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1004 | return ret; |
| 1005 | } |
| 1006 | |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1007 | /** |
| 1008 | * tty_write_message - write a message to a certain tty, not just the console. |
| 1009 | * @tty: the destination tty_struct |
| 1010 | * @msg: the message to write |
| 1011 | * |
| 1012 | * This is used for messages that need to be redirected to a specific tty. |
| 1013 | * We don't put it into the syslog queue right now maybe in the future if |
| 1014 | * really needed. |
| 1015 | * |
| 1016 | * We must still hold the BKL and test the CLOSING flag for the moment. |
| 1017 | */ |
| 1018 | |
| 1019 | void tty_write_message(struct tty_struct *tty, char *msg) |
| 1020 | { |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1021 | if (tty) { |
| 1022 | mutex_lock(&tty->atomic_write_lock); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1023 | lock_kernel(); |
| 1024 | if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) { |
| 1025 | unlock_kernel(); |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1026 | tty->ops->write(tty, msg, strlen(msg)); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1027 | } else |
| 1028 | unlock_kernel(); |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1029 | tty_write_unlock(tty); |
| 1030 | } |
Alan Cox | 95f9bfc | 2008-10-13 10:39:23 +0100 | [diff] [blame] | 1031 | return; |
| 1032 | } |
| 1033 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1034 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1035 | /** |
| 1036 | * tty_write - write method for tty device file |
| 1037 | * @file: tty file pointer |
| 1038 | * @buf: user data to write |
| 1039 | * @count: bytes to write |
| 1040 | * @ppos: unused |
| 1041 | * |
| 1042 | * Write data to a tty device via the line discipline. |
| 1043 | * |
| 1044 | * Locking: |
| 1045 | * Locks the line discipline as required |
| 1046 | * Writes to the tty driver are serialized by the atomic_write_lock |
| 1047 | * and are then processed in chunks to the device. The line discipline |
Joe Peterson | a88a69c | 2009-01-02 13:40:53 +0000 | [diff] [blame] | 1048 | * write method will not be invoked in parallel for each device. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1049 | */ |
| 1050 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1051 | static ssize_t tty_write(struct file *file, const char __user *buf, |
| 1052 | size_t count, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1053 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1054 | struct tty_struct *tty; |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 1055 | struct inode *inode = file->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1056 | ssize_t ret; |
| 1057 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1058 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1059 | tty = (struct tty_struct *)file->private_data; |
| 1060 | if (tty_paranoia_check(tty, inode, "tty_write")) |
| 1061 | return -EIO; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1062 | if (!tty || !tty->ops->write || |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1063 | (test_bit(TTY_IO_ERROR, &tty->flags))) |
| 1064 | return -EIO; |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1065 | /* Short term debug to catch buggy drivers */ |
| 1066 | if (tty->ops->write_room == NULL) |
| 1067 | printk(KERN_ERR "tty driver %s lacks a write_room method.\n", |
| 1068 | tty->driver->name); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1069 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1070 | if (!ld->ops->write) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1071 | ret = -EIO; |
| 1072 | else |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1073 | ret = do_tty_write(ld->ops->write, tty, file, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1074 | tty_ldisc_deref(ld); |
| 1075 | return ret; |
| 1076 | } |
| 1077 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1078 | ssize_t redirected_tty_write(struct file *file, const char __user *buf, |
| 1079 | size_t count, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1080 | { |
| 1081 | struct file *p = NULL; |
| 1082 | |
| 1083 | spin_lock(&redirect_lock); |
| 1084 | if (redirect) { |
| 1085 | get_file(redirect); |
| 1086 | p = redirect; |
| 1087 | } |
| 1088 | spin_unlock(&redirect_lock); |
| 1089 | |
| 1090 | if (p) { |
| 1091 | ssize_t res; |
| 1092 | res = vfs_write(p, buf, count, &p->f_pos); |
| 1093 | fput(p); |
| 1094 | return res; |
| 1095 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1096 | return tty_write(file, buf, count, ppos); |
| 1097 | } |
| 1098 | |
| 1099 | static char ptychar[] = "pqrstuvwxyzabcde"; |
| 1100 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1101 | /** |
| 1102 | * pty_line_name - generate name for a pty |
| 1103 | * @driver: the tty driver in use |
| 1104 | * @index: the minor number |
| 1105 | * @p: output buffer of at least 6 bytes |
| 1106 | * |
| 1107 | * Generate a name from a driver reference and write it to the output |
| 1108 | * buffer. |
| 1109 | * |
| 1110 | * Locking: None |
| 1111 | */ |
| 1112 | 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] | 1113 | { |
| 1114 | int i = index + driver->name_base; |
| 1115 | /* ->name is initialized to "ttyp", but "tty" is expected */ |
| 1116 | sprintf(p, "%s%c%x", |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1117 | driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name, |
| 1118 | ptychar[i >> 4 & 0xf], i & 0xf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | } |
| 1120 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1121 | /** |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1122 | * tty_line_name - generate name for a tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1123 | * @driver: the tty driver in use |
| 1124 | * @index: the minor number |
| 1125 | * @p: output buffer of at least 7 bytes |
| 1126 | * |
| 1127 | * Generate a name from a driver reference and write it to the output |
| 1128 | * buffer. |
| 1129 | * |
| 1130 | * Locking: None |
| 1131 | */ |
| 1132 | 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] | 1133 | { |
| 1134 | sprintf(p, "%s%d", driver->name, index + driver->name_base); |
| 1135 | } |
| 1136 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1137 | /** |
| 1138 | * tty_driver_lookup_tty() - find an existing tty, if any |
| 1139 | * @driver: the driver for the tty |
| 1140 | * @idx: the minor number |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1141 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1142 | * Return the tty, if found or ERR_PTR() otherwise. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1143 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1144 | * Locking: tty_mutex must be held. If tty is found, the mutex must |
| 1145 | * be held until the 'fast-open' is also done. Will change once we |
| 1146 | * have refcounting in the driver and per driver locking |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1147 | */ |
Jason Wessel | a47d545 | 2009-01-02 13:43:04 +0000 | [diff] [blame] | 1148 | static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1149 | struct inode *inode, int idx) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1150 | { |
| 1151 | struct tty_struct *tty; |
| 1152 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1153 | if (driver->ops->lookup) |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1154 | return driver->ops->lookup(driver, inode, idx); |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1155 | |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1156 | tty = driver->ttys[idx]; |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1157 | return tty; |
| 1158 | } |
| 1159 | |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1160 | /** |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1161 | * tty_init_termios - helper for termios setup |
| 1162 | * @tty: the tty to set up |
| 1163 | * |
| 1164 | * Initialise the termios structures for this tty. Thus runs under |
| 1165 | * the tty_mutex currently so we can be relaxed about ordering. |
| 1166 | */ |
| 1167 | |
| 1168 | int tty_init_termios(struct tty_struct *tty) |
| 1169 | { |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 1170 | struct ktermios *tp; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1171 | int idx = tty->index; |
| 1172 | |
| 1173 | tp = tty->driver->termios[idx]; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1174 | if (tp == NULL) { |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 1175 | tp = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL); |
| 1176 | if (tp == NULL) |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1177 | return -ENOMEM; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1178 | memcpy(tp, &tty->driver->init_termios, |
| 1179 | sizeof(struct ktermios)); |
| 1180 | tty->driver->termios[idx] = tp; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1181 | } |
| 1182 | tty->termios = tp; |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 1183 | tty->termios_locked = tp + 1; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1184 | |
| 1185 | /* Compatibility until drivers always set this */ |
| 1186 | tty->termios->c_ispeed = tty_termios_input_baud_rate(tty->termios); |
| 1187 | tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios); |
| 1188 | return 0; |
| 1189 | } |
Alan Cox | fe1ae7f | 2009-09-19 13:13:33 -0700 | [diff] [blame] | 1190 | EXPORT_SYMBOL_GPL(tty_init_termios); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1191 | |
| 1192 | /** |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1193 | * tty_driver_install_tty() - install a tty entry in the driver |
| 1194 | * @driver: the driver for the tty |
| 1195 | * @tty: the tty |
| 1196 | * |
| 1197 | * Install a tty object into the driver tables. The tty->index field |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1198 | * will be set by the time this is called. This method is responsible |
| 1199 | * for ensuring any need additional structures are allocated and |
| 1200 | * configured. |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1201 | * |
| 1202 | * Locking: tty_mutex for now |
| 1203 | */ |
| 1204 | static int tty_driver_install_tty(struct tty_driver *driver, |
| 1205 | struct tty_struct *tty) |
| 1206 | { |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1207 | int idx = tty->index; |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1208 | int ret; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1209 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1210 | if (driver->ops->install) { |
| 1211 | lock_kernel(); |
| 1212 | ret = driver->ops->install(driver, tty); |
| 1213 | unlock_kernel(); |
| 1214 | return ret; |
| 1215 | } |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1216 | |
| 1217 | if (tty_init_termios(tty) == 0) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1218 | lock_kernel(); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1219 | tty_driver_kref_get(driver); |
| 1220 | tty->count++; |
| 1221 | driver->ttys[idx] = tty; |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1222 | unlock_kernel(); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1223 | return 0; |
| 1224 | } |
| 1225 | return -ENOMEM; |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1226 | } |
| 1227 | |
| 1228 | /** |
| 1229 | * tty_driver_remove_tty() - remove a tty from the driver tables |
| 1230 | * @driver: the driver for the tty |
| 1231 | * @idx: the minor number |
| 1232 | * |
| 1233 | * Remvoe a tty object from the driver tables. The tty->index field |
| 1234 | * will be set by the time this is called. |
| 1235 | * |
| 1236 | * Locking: tty_mutex for now |
| 1237 | */ |
| 1238 | static void tty_driver_remove_tty(struct tty_driver *driver, |
| 1239 | struct tty_struct *tty) |
| 1240 | { |
| 1241 | if (driver->ops->remove) |
| 1242 | driver->ops->remove(driver, tty); |
| 1243 | else |
| 1244 | driver->ttys[tty->index] = NULL; |
| 1245 | } |
| 1246 | |
| 1247 | /* |
| 1248 | * tty_reopen() - fast re-open of an open tty |
| 1249 | * @tty - the tty to open |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1250 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1251 | * Return 0 on success, -errno on error. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1252 | * |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1253 | * Locking: tty_mutex must be held from the time the tty was found |
| 1254 | * till this open completes. |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1255 | */ |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1256 | static int tty_reopen(struct tty_struct *tty) |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1257 | { |
| 1258 | struct tty_driver *driver = tty->driver; |
| 1259 | |
| 1260 | if (test_bit(TTY_CLOSING, &tty->flags)) |
| 1261 | return -EIO; |
| 1262 | |
| 1263 | if (driver->type == TTY_DRIVER_TYPE_PTY && |
| 1264 | driver->subtype == PTY_TYPE_MASTER) { |
| 1265 | /* |
| 1266 | * special case for PTY masters: only one open permitted, |
| 1267 | * and the slave side open count is incremented as well. |
| 1268 | */ |
| 1269 | if (tty->count) |
| 1270 | return -EIO; |
| 1271 | |
| 1272 | tty->link->count++; |
| 1273 | } |
| 1274 | tty->count++; |
| 1275 | tty->driver = driver; /* N.B. why do this every time?? */ |
| 1276 | |
Alan Cox | 1aa4bed | 2009-06-16 17:01:33 +0100 | [diff] [blame] | 1277 | mutex_lock(&tty->ldisc_mutex); |
Alan Cox | 99f1fe1 | 2008-10-13 10:42:00 +0100 | [diff] [blame] | 1278 | WARN_ON(!test_bit(TTY_LDISC, &tty->flags)); |
Alan Cox | 1aa4bed | 2009-06-16 17:01:33 +0100 | [diff] [blame] | 1279 | mutex_unlock(&tty->ldisc_mutex); |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1280 | |
| 1281 | return 0; |
| 1282 | } |
| 1283 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1284 | /** |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1285 | * tty_init_dev - initialise a tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1286 | * @driver: tty driver we are opening a device on |
| 1287 | * @idx: device index |
Alan Cox | 15582d3 | 2008-10-13 10:41:03 +0100 | [diff] [blame] | 1288 | * @ret_tty: returned tty structure |
| 1289 | * @first_ok: ok to open a new device (used by ptmx) |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1290 | * |
| 1291 | * Prepare a tty device. This may not be a "new" clean device but |
| 1292 | * could also be an active device. The pty drivers require special |
| 1293 | * handling because of this. |
| 1294 | * |
| 1295 | * Locking: |
| 1296 | * The function is called under the tty_mutex, which |
| 1297 | * protects us from the tty struct or driver itself going away. |
| 1298 | * |
| 1299 | * On exit the tty device has the line discipline attached and |
| 1300 | * a reference count of 1. If a pair was created for pty/tty use |
| 1301 | * and the other was a pty master then it too has a reference count of 1. |
| 1302 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1303 | * 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] | 1304 | * failed open. The new code protects the open with a mutex, so it's |
| 1305 | * really quite straightforward. The mutex locking can probably be |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1306 | * relaxed for the (most common) case of reopening a tty. |
| 1307 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1308 | |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1309 | struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx, |
| 1310 | int first_ok) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1311 | { |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1312 | struct tty_struct *tty; |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1313 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1314 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1315 | lock_kernel(); |
Sukadev Bhattiprolu | 2349970 | 2008-10-13 10:41:51 +0100 | [diff] [blame] | 1316 | /* Check if pty master is being opened multiple times */ |
Alan Cox | 15582d3 | 2008-10-13 10:41:03 +0100 | [diff] [blame] | 1317 | if (driver->subtype == PTY_TYPE_MASTER && |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1318 | (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) { |
| 1319 | unlock_kernel(); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1320 | return ERR_PTR(-EIO); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1321 | } |
| 1322 | unlock_kernel(); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1323 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1324 | /* |
| 1325 | * First time open is complex, especially for PTY devices. |
| 1326 | * This code guarantees that either everything succeeds and the |
| 1327 | * TTY is ready for operation, or else the table slots are vacated |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1328 | * and the allocated memory released. (Except that the termios |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1329 | * and locked termios may be retained.) |
| 1330 | */ |
| 1331 | |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1332 | if (!try_module_get(driver->owner)) |
| 1333 | return ERR_PTR(-ENODEV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1334 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1335 | tty = alloc_tty_struct(); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1336 | if (!tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1337 | goto fail_no_mem; |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1338 | initialize_tty_struct(tty, driver, idx); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1339 | |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1340 | retval = tty_driver_install_tty(driver, tty); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1341 | if (retval < 0) { |
| 1342 | free_tty_struct(tty); |
| 1343 | module_put(driver->owner); |
| 1344 | return ERR_PTR(retval); |
| 1345 | } |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1346 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1347 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1348 | * Structures all installed ... call the ldisc open routines. |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1349 | * If we fail here just call release_tty to clean up. No need |
| 1350 | * to decrement the use counts, as release_tty doesn't care. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1351 | */ |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 1352 | retval = tty_ldisc_setup(tty, tty->link); |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1353 | if (retval) |
| 1354 | goto release_mem_out; |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1355 | return tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1356 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1357 | fail_no_mem: |
| 1358 | module_put(driver->owner); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1359 | return ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1360 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1361 | /* call the tty release_tty routine to clean out this slot */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1362 | release_mem_out: |
Akinobu Mita | 4050914 | 2006-09-29 02:01:27 -0700 | [diff] [blame] | 1363 | if (printk_ratelimit()) |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1364 | printk(KERN_INFO "tty_init_dev: ldisc open failed, " |
Akinobu Mita | 4050914 | 2006-09-29 02:01:27 -0700 | [diff] [blame] | 1365 | "clearing slot %d\n", idx); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1366 | lock_kernel(); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1367 | release_tty(tty, idx); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1368 | unlock_kernel(); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1369 | return ERR_PTR(retval); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1370 | } |
| 1371 | |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1372 | void tty_free_termios(struct tty_struct *tty) |
| 1373 | { |
| 1374 | struct ktermios *tp; |
| 1375 | int idx = tty->index; |
| 1376 | /* Kill this flag and push into drivers for locking etc */ |
| 1377 | if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) { |
| 1378 | /* FIXME: Locking on ->termios array */ |
| 1379 | tp = tty->termios; |
| 1380 | tty->driver->termios[idx] = NULL; |
| 1381 | kfree(tp); |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1382 | } |
| 1383 | } |
| 1384 | EXPORT_SYMBOL(tty_free_termios); |
| 1385 | |
| 1386 | void tty_shutdown(struct tty_struct *tty) |
| 1387 | { |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1388 | tty_driver_remove_tty(tty->driver, tty); |
Alan Cox | feebed6 | 2008-10-13 10:41:30 +0100 | [diff] [blame] | 1389 | tty_free_termios(tty); |
| 1390 | } |
| 1391 | EXPORT_SYMBOL(tty_shutdown); |
| 1392 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1393 | /** |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1394 | * release_one_tty - release tty structure memory |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1395 | * @kref: kref of tty we are obliterating |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1396 | * |
| 1397 | * Releases memory associated with a tty structure, and clears out the |
| 1398 | * driver table slots. This function is called when a device is no longer |
| 1399 | * in use. It also gets called when setup of a device fails. |
| 1400 | * |
| 1401 | * Locking: |
| 1402 | * tty_mutex - sometimes only |
| 1403 | * takes the file list lock internally when working on the list |
| 1404 | * of ttys that the driver keeps. |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1405 | * |
| 1406 | * 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] | 1407 | * cleanup ops can sleep (needed for USB at least) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1408 | */ |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1409 | static void release_one_tty(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1410 | { |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1411 | struct tty_struct *tty = |
| 1412 | container_of(work, struct tty_struct, hangup_work); |
Alan Cox | 6f967f7 | 2008-10-13 10:37:36 +0100 | [diff] [blame] | 1413 | struct tty_driver *driver = tty->driver; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1414 | |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1415 | if (tty->ops->cleanup) |
| 1416 | tty->ops->cleanup(tty); |
| 1417 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1418 | tty->magic = 0; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 1419 | tty_driver_kref_put(driver); |
Alan Cox | 6f967f7 | 2008-10-13 10:37:36 +0100 | [diff] [blame] | 1420 | module_put(driver->owner); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1421 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1422 | file_list_lock(); |
| 1423 | list_del_init(&tty->tty_files); |
| 1424 | file_list_unlock(); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1425 | |
Oleg Nesterov | 6da8d86 | 2010-04-02 18:05:12 +0200 | [diff] [blame] | 1426 | put_pid(tty->pgrp); |
| 1427 | put_pid(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1428 | free_tty_struct(tty); |
| 1429 | } |
| 1430 | |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1431 | static void queue_release_one_tty(struct kref *kref) |
| 1432 | { |
| 1433 | struct tty_struct *tty = container_of(kref, struct tty_struct, kref); |
Dave Young | f278a2f | 2009-09-27 16:00:42 +0000 | [diff] [blame] | 1434 | |
| 1435 | if (tty->ops->shutdown) |
| 1436 | tty->ops->shutdown(tty); |
| 1437 | else |
| 1438 | tty_shutdown(tty); |
| 1439 | |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1440 | /* The hangup queue is now free so we can reuse it rather than |
| 1441 | waste a chunk of memory for each port */ |
| 1442 | INIT_WORK(&tty->hangup_work, release_one_tty); |
| 1443 | schedule_work(&tty->hangup_work); |
| 1444 | } |
| 1445 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1446 | /** |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1447 | * tty_kref_put - release a tty kref |
| 1448 | * @tty: tty device |
| 1449 | * |
| 1450 | * Release a reference to a tty device and if need be let the kref |
| 1451 | * layer destruct the object for us |
| 1452 | */ |
| 1453 | |
| 1454 | void tty_kref_put(struct tty_struct *tty) |
| 1455 | { |
| 1456 | if (tty) |
Alan Cox | b50989d | 2009-09-19 13:13:22 -0700 | [diff] [blame] | 1457 | kref_put(&tty->kref, queue_release_one_tty); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1458 | } |
| 1459 | EXPORT_SYMBOL(tty_kref_put); |
| 1460 | |
| 1461 | /** |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1462 | * release_tty - release tty structure memory |
| 1463 | * |
| 1464 | * Release both @tty and a possible linked partner (think pty pair), |
| 1465 | * and decrement the refcount of the backing module. |
| 1466 | * |
| 1467 | * Locking: |
| 1468 | * tty_mutex - sometimes only |
| 1469 | * takes the file list lock internally when working on the list |
| 1470 | * of ttys that the driver keeps. |
| 1471 | * FIXME: should we require tty_mutex is held here ?? |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1472 | * |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1473 | */ |
| 1474 | static void release_tty(struct tty_struct *tty, int idx) |
| 1475 | { |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1476 | /* This should always be true but check for the moment */ |
| 1477 | WARN_ON(tty->index != idx); |
| 1478 | |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1479 | if (tty->link) |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 1480 | tty_kref_put(tty->link); |
| 1481 | tty_kref_put(tty); |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1482 | } |
| 1483 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1484 | /** |
| 1485 | * tty_release - vfs callback for close |
| 1486 | * @inode: inode of tty |
| 1487 | * @filp: file pointer for handle to tty |
| 1488 | * |
| 1489 | * Called the last time each file handle is closed that references |
| 1490 | * this tty. There may however be several such references. |
| 1491 | * |
| 1492 | * Locking: |
| 1493 | * Takes bkl. See tty_release_dev |
| 1494 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1495 | * Even releasing the tty structures is a tricky business.. We have |
| 1496 | * to be very careful that the structures are all released at the |
| 1497 | * same time, as interrupts might otherwise get the wrong pointers. |
| 1498 | * |
| 1499 | * WSH 09/09/97: rewritten to avoid some nasty race conditions that could |
| 1500 | * lead to double frees or releasing memory still in use. |
| 1501 | */ |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1502 | |
| 1503 | int tty_release(struct inode *inode, struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1504 | { |
| 1505 | struct tty_struct *tty, *o_tty; |
| 1506 | int pty_master, tty_closing, o_tty_closing, do_sleep; |
Paul Fulghum | 14a6283 | 2006-04-10 22:54:19 -0700 | [diff] [blame] | 1507 | int devpts; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1508 | int idx; |
| 1509 | char buf[64]; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1510 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1511 | tty = (struct tty_struct *)filp->private_data; |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1512 | if (tty_paranoia_check(tty, inode, "tty_release_dev")) |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1513 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1514 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1515 | lock_kernel(); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1516 | check_tty_count(tty, "tty_release_dev"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1517 | |
| 1518 | tty_fasync(-1, filp, 0); |
| 1519 | |
| 1520 | idx = tty->index; |
| 1521 | pty_master = (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 1522 | tty->driver->subtype == PTY_TYPE_MASTER); |
| 1523 | devpts = (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) != 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1524 | o_tty = tty->link; |
| 1525 | |
| 1526 | #ifdef TTY_PARANOIA_CHECK |
| 1527 | if (idx < 0 || idx >= tty->driver->num) { |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1528 | printk(KERN_DEBUG "tty_release_dev: bad idx when trying to " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1529 | "free (%s)\n", tty->name); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1530 | unlock_kernel(); |
| 1531 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1532 | } |
Alan Cox | 8b0a88d | 2008-10-13 10:42:19 +0100 | [diff] [blame] | 1533 | if (!devpts) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1534 | if (tty != tty->driver->ttys[idx]) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1535 | unlock_kernel(); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1536 | printk(KERN_DEBUG "tty_release_dev: driver.table[%d] not tty " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1537 | "for (%s)\n", idx, tty->name); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1538 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1539 | } |
| 1540 | if (tty->termios != tty->driver->termios[idx]) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1541 | unlock_kernel(); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1542 | printk(KERN_DEBUG "tty_release_dev: driver.termios[%d] not termios " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1543 | "for (%s)\n", |
| 1544 | idx, tty->name); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1545 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1546 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1547 | } |
| 1548 | #endif |
| 1549 | |
| 1550 | #ifdef TTY_DEBUG_HANGUP |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1551 | printk(KERN_DEBUG "tty_release_dev of %s (tty count=%d)...", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1552 | tty_name(tty, buf), tty->count); |
| 1553 | #endif |
| 1554 | |
| 1555 | #ifdef TTY_PARANOIA_CHECK |
| 1556 | if (tty->driver->other && |
| 1557 | !(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) { |
| 1558 | if (o_tty != tty->driver->other->ttys[idx]) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1559 | unlock_kernel(); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1560 | printk(KERN_DEBUG "tty_release_dev: other->table[%d] " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1561 | "not o_tty for (%s)\n", |
| 1562 | idx, tty->name); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1563 | return 0 ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1564 | } |
| 1565 | if (o_tty->termios != tty->driver->other->termios[idx]) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1566 | unlock_kernel(); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1567 | printk(KERN_DEBUG "tty_release_dev: other->termios[%d] " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1568 | "not o_termios for (%s)\n", |
| 1569 | idx, tty->name); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1570 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1571 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1572 | if (o_tty->link != tty) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1573 | unlock_kernel(); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1574 | printk(KERN_DEBUG "tty_release_dev: bad pty pointers\n"); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1575 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1576 | } |
| 1577 | } |
| 1578 | #endif |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1579 | if (tty->ops->close) |
| 1580 | tty->ops->close(tty, filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1581 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1582 | unlock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1583 | /* |
| 1584 | * Sanity check: if tty->count is going to zero, there shouldn't be |
| 1585 | * any waiters on tty->read_wait or tty->write_wait. We test the |
| 1586 | * wait queues and kick everyone out _before_ actually starting to |
| 1587 | * close. This ensures that we won't block while releasing the tty |
| 1588 | * structure. |
| 1589 | * |
| 1590 | * The test for the o_tty closing is necessary, since the master and |
| 1591 | * slave sides may close in any order. If the slave side closes out |
| 1592 | * first, its count will be one, since the master side holds an open. |
| 1593 | * Thus this test wouldn't be triggered at the time the slave closes, |
| 1594 | * so we do it now. |
| 1595 | * |
| 1596 | * Note that it's possible for the tty to be opened again while we're |
| 1597 | * flushing out waiters. By recalculating the closing flags before |
| 1598 | * each iteration we avoid any problems. |
| 1599 | */ |
| 1600 | while (1) { |
| 1601 | /* Guard against races with tty->count changes elsewhere and |
| 1602 | opens on /dev/tty */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1603 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1604 | mutex_lock(&tty_mutex); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1605 | lock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1606 | tty_closing = tty->count <= 1; |
| 1607 | o_tty_closing = o_tty && |
| 1608 | (o_tty->count <= (pty_master ? 1 : 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1609 | do_sleep = 0; |
| 1610 | |
| 1611 | if (tty_closing) { |
| 1612 | if (waitqueue_active(&tty->read_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1613 | wake_up_poll(&tty->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1614 | do_sleep++; |
| 1615 | } |
| 1616 | if (waitqueue_active(&tty->write_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1617 | wake_up_poll(&tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1618 | do_sleep++; |
| 1619 | } |
| 1620 | } |
| 1621 | if (o_tty_closing) { |
| 1622 | if (waitqueue_active(&o_tty->read_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1623 | wake_up_poll(&o_tty->read_wait, POLLIN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1624 | do_sleep++; |
| 1625 | } |
| 1626 | if (waitqueue_active(&o_tty->write_wait)) { |
Davide Libenzi | 4b19449 | 2009-03-31 15:24:24 -0700 | [diff] [blame] | 1627 | wake_up_poll(&o_tty->write_wait, POLLOUT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1628 | do_sleep++; |
| 1629 | } |
| 1630 | } |
| 1631 | if (!do_sleep) |
| 1632 | break; |
| 1633 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1634 | printk(KERN_WARNING "tty_release_dev: %s: read/write wait queue " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1635 | "active!\n", tty_name(tty, buf)); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1636 | unlock_kernel(); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1637 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1638 | schedule(); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1639 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1640 | |
| 1641 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1642 | * The closing flags are now consistent with the open counts on |
| 1643 | * both sides, and we've completed the last operation that could |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1644 | * block, so it's safe to proceed with closing. |
| 1645 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1646 | if (pty_master) { |
| 1647 | if (--o_tty->count < 0) { |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1648 | printk(KERN_WARNING "tty_release_dev: bad pty slave count " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1649 | "(%d) for %s\n", |
| 1650 | o_tty->count, tty_name(o_tty, buf)); |
| 1651 | o_tty->count = 0; |
| 1652 | } |
| 1653 | } |
| 1654 | if (--tty->count < 0) { |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1655 | printk(KERN_WARNING "tty_release_dev: bad tty->count (%d) for %s\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1656 | tty->count, tty_name(tty, buf)); |
| 1657 | tty->count = 0; |
| 1658 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1659 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1660 | /* |
| 1661 | * We've decremented tty->count, so we need to remove this file |
| 1662 | * descriptor off the tty->tty_files list; this serves two |
| 1663 | * purposes: |
| 1664 | * - check_tty_count sees the correct number of file descriptors |
| 1665 | * associated with this tty. |
| 1666 | * - do_tty_hangup no longer sees this file descriptor as |
| 1667 | * something that needs to be handled for hangups. |
| 1668 | */ |
| 1669 | file_kill(filp); |
| 1670 | filp->private_data = NULL; |
| 1671 | |
| 1672 | /* |
| 1673 | * Perform some housekeeping before deciding whether to return. |
| 1674 | * |
| 1675 | * Set the TTY_CLOSING flag if this was the last open. In the |
| 1676 | * case of a pty we may have to wait around for the other side |
| 1677 | * to close, and TTY_CLOSING makes sure we can't be reopened. |
| 1678 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1679 | if (tty_closing) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1680 | set_bit(TTY_CLOSING, &tty->flags); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1681 | if (o_tty_closing) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1682 | set_bit(TTY_CLOSING, &o_tty->flags); |
| 1683 | |
| 1684 | /* |
| 1685 | * If _either_ side is closing, make sure there aren't any |
| 1686 | * processes that still think tty or o_tty is their controlling |
| 1687 | * tty. |
| 1688 | */ |
| 1689 | if (tty_closing || o_tty_closing) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1690 | read_lock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1691 | session_clear_tty(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1692 | if (o_tty) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1693 | session_clear_tty(o_tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1694 | read_unlock(&tasklist_lock); |
| 1695 | } |
| 1696 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1697 | mutex_unlock(&tty_mutex); |
Paul Fulghum | da96582 | 2006-02-14 13:53:00 -0800 | [diff] [blame] | 1698 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1699 | /* check whether both sides are closing ... */ |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1700 | if (!tty_closing || (o_tty && !o_tty_closing)) { |
| 1701 | unlock_kernel(); |
| 1702 | return 0; |
| 1703 | } |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1704 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1705 | #ifdef TTY_DEBUG_HANGUP |
| 1706 | printk(KERN_DEBUG "freeing tty structure..."); |
| 1707 | #endif |
| 1708 | /* |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1709 | * Ask the line discipline code to release its structures |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1710 | */ |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 1711 | tty_ldisc_release(tty, o_tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1712 | /* |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1713 | * The release_tty function takes care of the details of clearing |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1714 | * the slots and preserving the termios structure. |
| 1715 | */ |
Christoph Hellwig | d5698c2 | 2007-02-10 01:46:46 -0800 | [diff] [blame] | 1716 | release_tty(tty, idx); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1717 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1718 | /* Make this pty number available for reallocation */ |
Sukadev Bhattiprolu | 718a916 | 2008-04-30 00:54:21 -0700 | [diff] [blame] | 1719 | if (devpts) |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1720 | devpts_kill_index(inode, idx); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1721 | unlock_kernel(); |
| 1722 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1723 | } |
| 1724 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1725 | /** |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1726 | * tty_open - open a tty device |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1727 | * @inode: inode of device file |
| 1728 | * @filp: file pointer to tty |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1729 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1730 | * tty_open and tty_release keep up the tty count that contains the |
| 1731 | * number of opens done on a tty. We cannot use the inode-count, as |
| 1732 | * different inodes might point to the same tty. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1733 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1734 | * Open-counting is needed for pty masters, as well as for keeping |
| 1735 | * track of serial lines: DTR is dropped when the last close happens. |
| 1736 | * (This is not done solely through tty->count, now. - Ted 1/27/92) |
| 1737 | * |
| 1738 | * The termios state of a pty is reset on first open so that |
| 1739 | * settings don't persist across reuse. |
| 1740 | * |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 1741 | * Locking: tty_mutex protects tty, get_tty_driver and tty_init_dev work. |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1742 | * tty->count should protect the rest. |
| 1743 | * ->siglock protects ->signal/->sighand |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1744 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1745 | |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1746 | static int tty_open(struct inode *inode, struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1747 | { |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1748 | struct tty_struct *tty = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1749 | int noctty, retval; |
| 1750 | struct tty_driver *driver; |
| 1751 | int index; |
| 1752 | dev_t device = inode->i_rdev; |
Andrew Morton | 846c151 | 2009-04-02 16:56:36 -0700 | [diff] [blame] | 1753 | unsigned saved_flags = filp->f_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1754 | |
| 1755 | nonseekable_open(inode, filp); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1756 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1757 | retry_open: |
| 1758 | noctty = filp->f_flags & O_NOCTTY; |
| 1759 | index = -1; |
| 1760 | retval = 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1761 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1762 | mutex_lock(&tty_mutex); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1763 | lock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1764 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1765 | if (device == MKDEV(TTYAUX_MAJOR, 0)) { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1766 | tty = get_current_tty(); |
| 1767 | if (!tty) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1768 | unlock_kernel(); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1769 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1770 | return -ENXIO; |
| 1771 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 1772 | driver = tty_driver_kref_get(tty->driver); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1773 | index = tty->index; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1774 | filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ |
| 1775 | /* noctty = 1; */ |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 1776 | /* FIXME: Should we take a driver reference ? */ |
| 1777 | tty_kref_put(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1778 | goto got_driver; |
| 1779 | } |
| 1780 | #ifdef CONFIG_VT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1781 | if (device == MKDEV(TTY_MAJOR, 0)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1782 | extern struct tty_driver *console_driver; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 1783 | driver = tty_driver_kref_get(console_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1784 | index = fg_console; |
| 1785 | noctty = 1; |
| 1786 | goto got_driver; |
| 1787 | } |
| 1788 | #endif |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1789 | if (device == MKDEV(TTYAUX_MAJOR, 1)) { |
Will Newton | 296fa7f | 2008-12-01 11:36:06 +0000 | [diff] [blame] | 1790 | struct tty_driver *console_driver = console_device(&index); |
| 1791 | if (console_driver) { |
| 1792 | driver = tty_driver_kref_get(console_driver); |
| 1793 | if (driver) { |
| 1794 | /* Don't let /dev/console block */ |
| 1795 | filp->f_flags |= O_NONBLOCK; |
| 1796 | noctty = 1; |
| 1797 | goto got_driver; |
| 1798 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1799 | } |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1800 | unlock_kernel(); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1801 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1802 | return -ENODEV; |
| 1803 | } |
| 1804 | |
| 1805 | driver = get_tty_driver(device, &index); |
| 1806 | if (!driver) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1807 | unlock_kernel(); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1808 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1809 | return -ENODEV; |
| 1810 | } |
| 1811 | got_driver: |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1812 | if (!tty) { |
| 1813 | /* check whether we're reopening an existing tty */ |
Sukadev Bhattiprolu | 15f1a63 | 2008-10-13 10:42:59 +0100 | [diff] [blame] | 1814 | tty = tty_driver_lookup_tty(driver, inode, index); |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1815 | |
Eric Paris | 808ffa3 | 2009-01-27 11:50:37 +0000 | [diff] [blame] | 1816 | if (IS_ERR(tty)) { |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1817 | unlock_kernel(); |
Eric Paris | 808ffa3 | 2009-01-27 11:50:37 +0000 | [diff] [blame] | 1818 | mutex_unlock(&tty_mutex); |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1819 | return PTR_ERR(tty); |
Eric Paris | 808ffa3 | 2009-01-27 11:50:37 +0000 | [diff] [blame] | 1820 | } |
Sukadev Bhattiprolu | 4a2b5fd | 2008-10-13 10:42:49 +0100 | [diff] [blame] | 1821 | } |
| 1822 | |
| 1823 | if (tty) { |
| 1824 | retval = tty_reopen(tty); |
| 1825 | if (retval) |
| 1826 | tty = ERR_PTR(retval); |
| 1827 | } else |
| 1828 | tty = tty_init_dev(driver, index, 0); |
| 1829 | |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 1830 | mutex_unlock(&tty_mutex); |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 1831 | tty_driver_kref_put(driver); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1832 | if (IS_ERR(tty)) { |
| 1833 | unlock_kernel(); |
Alan Cox | 73ec06f | 2008-10-13 10:42:29 +0100 | [diff] [blame] | 1834 | return PTR_ERR(tty); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1835 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1836 | |
| 1837 | filp->private_data = tty; |
| 1838 | file_move(filp, &tty->tty_files); |
| 1839 | check_tty_count(tty, "tty_open"); |
| 1840 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 1841 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 1842 | noctty = 1; |
| 1843 | #ifdef TTY_DEBUG_HANGUP |
| 1844 | printk(KERN_DEBUG "opening %s...", tty->name); |
| 1845 | #endif |
| 1846 | if (!retval) { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 1847 | if (tty->ops->open) |
| 1848 | retval = tty->ops->open(tty, filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1849 | else |
| 1850 | retval = -ENODEV; |
| 1851 | } |
| 1852 | filp->f_flags = saved_flags; |
| 1853 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1854 | if (!retval && test_bit(TTY_EXCLUSIVE, &tty->flags) && |
| 1855 | !capable(CAP_SYS_ADMIN)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1856 | retval = -EBUSY; |
| 1857 | |
| 1858 | if (retval) { |
| 1859 | #ifdef TTY_DEBUG_HANGUP |
| 1860 | printk(KERN_DEBUG "error %d in opening %s...", retval, |
| 1861 | tty->name); |
| 1862 | #endif |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1863 | tty_release(inode, filp); |
| 1864 | if (retval != -ERESTARTSYS) { |
| 1865 | unlock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1866 | return retval; |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1867 | } |
| 1868 | if (signal_pending(current)) { |
| 1869 | unlock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1870 | return retval; |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1871 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1872 | schedule(); |
| 1873 | /* |
| 1874 | * Need to reset f_op in case a hangup happened. |
| 1875 | */ |
| 1876 | if (filp->f_op == &hung_up_tty_fops) |
| 1877 | filp->f_op = &tty_fops; |
Alan Cox | 77945fe | 2010-05-04 20:42:36 +0100 | [diff] [blame] | 1878 | unlock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1879 | goto retry_open; |
| 1880 | } |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1881 | unlock_kernel(); |
| 1882 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1883 | |
| 1884 | mutex_lock(&tty_mutex); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1885 | lock_kernel(); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1886 | spin_lock_irq(¤t->sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1887 | if (!noctty && |
| 1888 | current->signal->leader && |
| 1889 | !current->signal->tty && |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 1890 | tty->session == NULL) |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 1891 | __proc_set_tty(current, tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1892 | spin_unlock_irq(¤t->sighand->siglock); |
Alan Cox | eeb89d9 | 2009-11-30 13:18:29 +0000 | [diff] [blame] | 1893 | unlock_kernel(); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 1894 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1895 | return 0; |
| 1896 | } |
| 1897 | |
Jonathan Corbet | 39d95b9 | 2008-05-16 09:10:50 -0600 | [diff] [blame] | 1898 | |
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 | /** |
| 1901 | * tty_poll - check tty status |
| 1902 | * @filp: file being polled |
| 1903 | * @wait: poll wait structures to update |
| 1904 | * |
| 1905 | * Call the line discipline polling method to obtain the poll |
| 1906 | * status of the device. |
| 1907 | * |
| 1908 | * Locking: locks called line discipline but ldisc poll method |
| 1909 | * may be re-entered freely by other callers. |
| 1910 | */ |
| 1911 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1912 | static unsigned int tty_poll(struct file *filp, poll_table *wait) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1913 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1914 | struct tty_struct *tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1915 | struct tty_ldisc *ld; |
| 1916 | int ret = 0; |
| 1917 | |
| 1918 | tty = (struct tty_struct *)filp->private_data; |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 1919 | 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] | 1920 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1921 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1922 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 1923 | if (ld->ops->poll) |
| 1924 | ret = (ld->ops->poll)(tty, filp, wait); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1925 | tty_ldisc_deref(ld); |
| 1926 | return ret; |
| 1927 | } |
| 1928 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1929 | static int tty_fasync(int fd, struct file *filp, int on) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1930 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1931 | struct tty_struct *tty; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 1932 | unsigned long flags; |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 1933 | int retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1934 | |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 1935 | lock_kernel(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1936 | tty = (struct tty_struct *)filp->private_data; |
Josef Sipek | a7113a9 | 2006-12-08 02:36:55 -0800 | [diff] [blame] | 1937 | 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] | 1938 | goto out; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1939 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1940 | retval = fasync_helper(fd, filp, on, &tty->fasync); |
| 1941 | if (retval <= 0) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 1942 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1943 | |
| 1944 | if (on) { |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 1945 | enum pid_type type; |
| 1946 | struct pid *pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1947 | if (!waitqueue_active(&tty->read_wait)) |
| 1948 | tty->minimum_to_wake = 1; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 1949 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 1950 | if (tty->pgrp) { |
| 1951 | pid = tty->pgrp; |
| 1952 | type = PIDTYPE_PGID; |
| 1953 | } else { |
| 1954 | pid = task_pid(current); |
| 1955 | type = PIDTYPE_PID; |
| 1956 | } |
Linus Torvalds | 80e1e82 | 2010-02-07 10:11:23 -0800 | [diff] [blame] | 1957 | get_pid(pid); |
Greg Kroah-Hartman | 7036251 | 2009-12-17 07:07:19 -0800 | [diff] [blame] | 1958 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Linus Torvalds | 80e1e82 | 2010-02-07 10:11:23 -0800 | [diff] [blame] | 1959 | retval = __f_setown(filp, pid, type, 0); |
| 1960 | put_pid(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1961 | if (retval) |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 1962 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1963 | } else { |
| 1964 | if (!tty->fasync && !waitqueue_active(&tty->read_wait)) |
| 1965 | tty->minimum_to_wake = N_TTY_BUF_SIZE; |
| 1966 | } |
Jonathan Corbet | 5d1e323 | 2008-06-19 16:04:53 -0600 | [diff] [blame] | 1967 | retval = 0; |
| 1968 | out: |
| 1969 | unlock_kernel(); |
| 1970 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1971 | } |
| 1972 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1973 | /** |
| 1974 | * tiocsti - fake input character |
| 1975 | * @tty: tty to fake input into |
| 1976 | * @p: pointer to character |
| 1977 | * |
Robert P. J. Day | 3a4fa0a | 2007-10-19 23:10:43 +0200 | [diff] [blame] | 1978 | * Fake input to a tty device. Does the necessary locking and |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1979 | * input management. |
| 1980 | * |
| 1981 | * FIXME: does not honour flow control ?? |
| 1982 | * |
| 1983 | * Locking: |
| 1984 | * Called functions take tty_ldisc_lock |
| 1985 | * current->signal->tty check is safe without locks |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 1986 | * |
| 1987 | * FIXME: may race normal receive processing |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 1988 | */ |
| 1989 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1990 | static int tiocsti(struct tty_struct *tty, char __user *p) |
| 1991 | { |
| 1992 | char ch, mbz = 0; |
| 1993 | struct tty_ldisc *ld; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 1994 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1995 | if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN)) |
| 1996 | return -EPERM; |
| 1997 | if (get_user(ch, p)) |
| 1998 | return -EFAULT; |
Al Viro | 1e64174 | 2008-12-09 09:23:33 +0000 | [diff] [blame] | 1999 | tty_audit_tiocsti(tty, ch); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2000 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2001 | ld->ops->receive_buf(tty, &ch, &mbz, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2002 | tty_ldisc_deref(ld); |
| 2003 | return 0; |
| 2004 | } |
| 2005 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2006 | /** |
| 2007 | * tiocgwinsz - implement window query ioctl |
| 2008 | * @tty; tty |
| 2009 | * @arg: user buffer for result |
| 2010 | * |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2011 | * Copies the kernel idea of the window size into the user buffer. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2012 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2013 | * Locking: tty->termios_mutex is taken to ensure the winsize data |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2014 | * is consistent. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2015 | */ |
| 2016 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2017 | static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2018 | { |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2019 | int err; |
| 2020 | |
Arjan van de Ven | 5785c95 | 2006-09-29 02:00:43 -0700 | [diff] [blame] | 2021 | mutex_lock(&tty->termios_mutex); |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2022 | err = copy_to_user(arg, &tty->winsize, sizeof(*arg)); |
Arjan van de Ven | 5785c95 | 2006-09-29 02:00:43 -0700 | [diff] [blame] | 2023 | mutex_unlock(&tty->termios_mutex); |
Alan Cox | 808a0d3 | 2006-09-29 02:00:40 -0700 | [diff] [blame] | 2024 | |
| 2025 | return err ? -EFAULT: 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2026 | } |
| 2027 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2028 | /** |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2029 | * tty_do_resize - resize event |
| 2030 | * @tty: tty being resized |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2031 | * @rows: rows (character) |
| 2032 | * @cols: cols (character) |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2033 | * |
Daniel Mack | 3ad2f3f | 2010-02-03 08:01:28 +0800 | [diff] [blame] | 2034 | * Update the termios variables and send the necessary signals to |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2035 | * peform a terminal resize correctly |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2036 | */ |
| 2037 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2038 | int tty_do_resize(struct tty_struct *tty, struct winsize *ws) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2039 | { |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2040 | struct pid *pgrp; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2041 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2042 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2043 | /* Lock the tty */ |
| 2044 | mutex_lock(&tty->termios_mutex); |
| 2045 | if (!memcmp(ws, &tty->winsize, sizeof(*ws))) |
Alan Cox | ca9bda0 | 2006-09-29 02:00:03 -0700 | [diff] [blame] | 2046 | goto done; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2047 | /* Get the PID values and reference them so we can |
| 2048 | avoid holding the tty ctrl lock while sending signals */ |
| 2049 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 2050 | pgrp = get_pid(tty->pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2051 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 2052 | |
| 2053 | if (pgrp) |
| 2054 | kill_pgrp(pgrp, SIGWINCH, 1); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2055 | put_pid(pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2056 | |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2057 | tty->winsize = *ws; |
Alan Cox | ca9bda0 | 2006-09-29 02:00:03 -0700 | [diff] [blame] | 2058 | done: |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2059 | mutex_unlock(&tty->termios_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2060 | return 0; |
| 2061 | } |
| 2062 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2063 | /** |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2064 | * tiocswinsz - implement window size set ioctl |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2065 | * @tty; tty side of tty |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2066 | * @arg: user buffer for result |
| 2067 | * |
| 2068 | * Copies the user idea of the window size to the kernel. Traditionally |
| 2069 | * this is just advisory information but for the Linux console it |
| 2070 | * actually has driver level meaning and triggers a VC resize. |
| 2071 | * |
| 2072 | * Locking: |
| 2073 | * Driver dependant. The default do_resize method takes the |
| 2074 | * tty termios mutex and ctrl_lock. The console takes its own lock |
| 2075 | * then calls into the default method. |
| 2076 | */ |
| 2077 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2078 | static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2079 | { |
| 2080 | struct winsize tmp_ws; |
| 2081 | if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) |
| 2082 | return -EFAULT; |
| 2083 | |
| 2084 | if (tty->ops->resize) |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2085 | return tty->ops->resize(tty, &tmp_ws); |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2086 | else |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2087 | return tty_do_resize(tty, &tmp_ws); |
Alan Cox | 8c9a9dd | 2008-08-15 10:39:38 +0100 | [diff] [blame] | 2088 | } |
| 2089 | |
| 2090 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2091 | * tioccons - allow admin to move logical console |
| 2092 | * @file: the file to become console |
| 2093 | * |
| 2094 | * Allow the adminstrator to move the redirected console device |
| 2095 | * |
| 2096 | * Locking: uses redirect_lock to guard the redirect information |
| 2097 | */ |
| 2098 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2099 | static int tioccons(struct file *file) |
| 2100 | { |
| 2101 | if (!capable(CAP_SYS_ADMIN)) |
| 2102 | return -EPERM; |
| 2103 | if (file->f_op->write == redirected_tty_write) { |
| 2104 | struct file *f; |
| 2105 | spin_lock(&redirect_lock); |
| 2106 | f = redirect; |
| 2107 | redirect = NULL; |
| 2108 | spin_unlock(&redirect_lock); |
| 2109 | if (f) |
| 2110 | fput(f); |
| 2111 | return 0; |
| 2112 | } |
| 2113 | spin_lock(&redirect_lock); |
| 2114 | if (redirect) { |
| 2115 | spin_unlock(&redirect_lock); |
| 2116 | return -EBUSY; |
| 2117 | } |
| 2118 | get_file(file); |
| 2119 | redirect = file; |
| 2120 | spin_unlock(&redirect_lock); |
| 2121 | return 0; |
| 2122 | } |
| 2123 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2124 | /** |
| 2125 | * fionbio - non blocking ioctl |
| 2126 | * @file: file to set blocking value |
| 2127 | * @p: user parameter |
| 2128 | * |
| 2129 | * Historical tty interfaces had a blocking control ioctl before |
| 2130 | * the generic functionality existed. This piece of history is preserved |
| 2131 | * in the expected tty API of posix OS's. |
| 2132 | * |
Alan Cox | 6146b9a | 2009-09-19 13:13:19 -0700 | [diff] [blame] | 2133 | * Locking: none, the open file handle ensures it won't go away. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2134 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2135 | |
| 2136 | static int fionbio(struct file *file, int __user *p) |
| 2137 | { |
| 2138 | int nonblock; |
| 2139 | |
| 2140 | if (get_user(nonblock, p)) |
| 2141 | return -EFAULT; |
| 2142 | |
Jonathan Corbet | db1dd4d | 2009-02-06 15:25:24 -0700 | [diff] [blame] | 2143 | spin_lock(&file->f_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2144 | if (nonblock) |
| 2145 | file->f_flags |= O_NONBLOCK; |
| 2146 | else |
| 2147 | file->f_flags &= ~O_NONBLOCK; |
Jonathan Corbet | db1dd4d | 2009-02-06 15:25:24 -0700 | [diff] [blame] | 2148 | spin_unlock(&file->f_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2149 | return 0; |
| 2150 | } |
| 2151 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2152 | /** |
| 2153 | * tiocsctty - set controlling tty |
| 2154 | * @tty: tty structure |
| 2155 | * @arg: user argument |
| 2156 | * |
| 2157 | * This ioctl is used to manage job control. It permits a session |
| 2158 | * leader to set this tty as the controlling tty for the session. |
| 2159 | * |
| 2160 | * Locking: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2161 | * Takes tty_mutex() to protect tty instance |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2162 | * Takes tasklist_lock internally to walk sessions |
| 2163 | * Takes ->siglock() when updating signal->tty |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2164 | */ |
| 2165 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2166 | static int tiocsctty(struct tty_struct *tty, int arg) |
| 2167 | { |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2168 | int ret = 0; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2169 | if (current->signal->leader && (task_session(current) == tty->session)) |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2170 | return ret; |
| 2171 | |
| 2172 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2173 | /* |
| 2174 | * The process must be a session leader and |
| 2175 | * not have a controlling tty already. |
| 2176 | */ |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2177 | if (!current->signal->leader || current->signal->tty) { |
| 2178 | ret = -EPERM; |
| 2179 | goto unlock; |
| 2180 | } |
| 2181 | |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2182 | if (tty->session) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2183 | /* |
| 2184 | * This tty is already the controlling |
| 2185 | * tty for another session group! |
| 2186 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2187 | if (arg == 1 && capable(CAP_SYS_ADMIN)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2188 | /* |
| 2189 | * Steal it away |
| 2190 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2191 | read_lock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2192 | session_clear_tty(tty->session); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2193 | read_unlock(&tasklist_lock); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2194 | } else { |
| 2195 | ret = -EPERM; |
| 2196 | goto unlock; |
| 2197 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2198 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2199 | proc_set_tty(current, tty); |
| 2200 | unlock: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2201 | mutex_unlock(&tty_mutex); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2202 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2203 | } |
| 2204 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2205 | /** |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2206 | * tty_get_pgrp - return a ref counted pgrp pid |
| 2207 | * @tty: tty to read |
| 2208 | * |
| 2209 | * Returns a refcounted instance of the pid struct for the process |
| 2210 | * group controlling the tty. |
| 2211 | */ |
| 2212 | |
| 2213 | struct pid *tty_get_pgrp(struct tty_struct *tty) |
| 2214 | { |
| 2215 | unsigned long flags; |
| 2216 | struct pid *pgrp; |
| 2217 | |
| 2218 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
| 2219 | pgrp = get_pid(tty->pgrp); |
| 2220 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 2221 | |
| 2222 | return pgrp; |
| 2223 | } |
| 2224 | EXPORT_SYMBOL_GPL(tty_get_pgrp); |
| 2225 | |
| 2226 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2227 | * tiocgpgrp - get process group |
| 2228 | * @tty: tty passed by user |
| 2229 | * @real_tty: tty side of the tty pased by the user if a pty else the tty |
| 2230 | * @p: returned pid |
| 2231 | * |
| 2232 | * Obtain the process group of the tty. If there is no process group |
| 2233 | * return an error. |
| 2234 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2235 | * Locking: none. Reference to current->signal->tty is safe. |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2236 | */ |
| 2237 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2238 | static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2239 | { |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2240 | struct pid *pid; |
| 2241 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2242 | /* |
| 2243 | * (tty == real_tty) is a cheap way of |
| 2244 | * testing if the tty is NOT a master pty. |
| 2245 | */ |
| 2246 | if (tty == real_tty && current->signal->tty != real_tty) |
| 2247 | return -ENOTTY; |
Alan Cox | 5d0fdf1 | 2008-04-30 00:53:31 -0700 | [diff] [blame] | 2248 | pid = tty_get_pgrp(real_tty); |
| 2249 | ret = put_user(pid_vnr(pid), p); |
| 2250 | put_pid(pid); |
| 2251 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2252 | } |
| 2253 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2254 | /** |
| 2255 | * tiocspgrp - attempt to set process group |
| 2256 | * @tty: tty passed by user |
| 2257 | * @real_tty: tty side device matching tty passed by user |
| 2258 | * @p: pid pointer |
| 2259 | * |
| 2260 | * Set the process group of the tty to the session passed. Only |
| 2261 | * permitted where the tty session is our session. |
| 2262 | * |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2263 | * Locking: RCU, ctrl lock |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2264 | */ |
| 2265 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2266 | static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2267 | { |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2268 | struct pid *pgrp; |
| 2269 | pid_t pgrp_nr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2270 | int retval = tty_check_change(real_tty); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2271 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2272 | |
| 2273 | if (retval == -EIO) |
| 2274 | return -ENOTTY; |
| 2275 | if (retval) |
| 2276 | return retval; |
| 2277 | if (!current->signal->tty || |
| 2278 | (current->signal->tty != real_tty) || |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2279 | (real_tty->session != task_session(current))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2280 | return -ENOTTY; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2281 | if (get_user(pgrp_nr, p)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2282 | return -EFAULT; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2283 | if (pgrp_nr < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2284 | return -EINVAL; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2285 | rcu_read_lock(); |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 2286 | pgrp = find_vpid(pgrp_nr); |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2287 | retval = -ESRCH; |
| 2288 | if (!pgrp) |
| 2289 | goto out_unlock; |
| 2290 | retval = -EPERM; |
| 2291 | if (session_of_pgrp(pgrp) != task_session(current)) |
| 2292 | goto out_unlock; |
| 2293 | retval = 0; |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2294 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2295 | put_pid(real_tty->pgrp); |
| 2296 | real_tty->pgrp = get_pid(pgrp); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 2297 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 2298 | out_unlock: |
| 2299 | rcu_read_unlock(); |
| 2300 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2301 | } |
| 2302 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2303 | /** |
| 2304 | * tiocgsid - get session id |
| 2305 | * @tty: tty passed by user |
| 2306 | * @real_tty: tty side of the tty pased by the user if a pty else the tty |
| 2307 | * @p: pointer to returned session id |
| 2308 | * |
| 2309 | * Obtain the session id of the tty. If there is no session |
| 2310 | * return an error. |
| 2311 | * |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2312 | * Locking: none. Reference to current->signal->tty is safe. |
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 tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) |
| 2316 | { |
| 2317 | /* |
| 2318 | * (tty == real_tty) is a cheap way of |
| 2319 | * testing if the tty is NOT a master pty. |
| 2320 | */ |
| 2321 | if (tty == real_tty && current->signal->tty != real_tty) |
| 2322 | return -ENOTTY; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2323 | if (!real_tty->session) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2324 | return -ENOTTY; |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 2325 | return put_user(pid_vnr(real_tty->session), p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2326 | } |
| 2327 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2328 | /** |
| 2329 | * tiocsetd - set line discipline |
| 2330 | * @tty: tty device |
| 2331 | * @p: pointer to user data |
| 2332 | * |
| 2333 | * Set the line discipline according to user request. |
| 2334 | * |
| 2335 | * Locking: see tty_set_ldisc, this function is just a helper |
| 2336 | */ |
| 2337 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2338 | static int tiocsetd(struct tty_struct *tty, int __user *p) |
| 2339 | { |
| 2340 | int ldisc; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2341 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2342 | |
| 2343 | if (get_user(ldisc, p)) |
| 2344 | return -EFAULT; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2345 | |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2346 | ret = tty_set_ldisc(tty, ldisc); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2347 | |
| 2348 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2349 | } |
| 2350 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2351 | /** |
| 2352 | * send_break - performed time break |
| 2353 | * @tty: device to break on |
| 2354 | * @duration: timeout in mS |
| 2355 | * |
| 2356 | * Perform a timed break on hardware that lacks its own driver level |
| 2357 | * timed break functionality. |
| 2358 | * |
| 2359 | * Locking: |
Alan Cox | 2829823 | 2006-09-29 02:00:58 -0700 | [diff] [blame] | 2360 | * atomic_write_lock serializes |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2361 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2362 | */ |
| 2363 | |
Domen Puncer | b20f3ae | 2005-06-25 14:58:42 -0700 | [diff] [blame] | 2364 | static int send_break(struct tty_struct *tty, unsigned int duration) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2365 | { |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2366 | int retval; |
| 2367 | |
| 2368 | if (tty->ops->break_ctl == NULL) |
| 2369 | return 0; |
| 2370 | |
| 2371 | if (tty->driver->flags & TTY_DRIVER_HARDWARE_BREAK) |
| 2372 | retval = tty->ops->break_ctl(tty, duration); |
| 2373 | else { |
| 2374 | /* Do the work ourselves */ |
| 2375 | if (tty_write_lock(tty, 0) < 0) |
| 2376 | return -EINTR; |
| 2377 | retval = tty->ops->break_ctl(tty, -1); |
| 2378 | if (retval) |
| 2379 | goto out; |
| 2380 | if (!signal_pending(current)) |
| 2381 | msleep_interruptible(duration); |
| 2382 | retval = tty->ops->break_ctl(tty, 0); |
| 2383 | out: |
| 2384 | tty_write_unlock(tty); |
| 2385 | if (signal_pending(current)) |
| 2386 | retval = -EINTR; |
| 2387 | } |
| 2388 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2389 | } |
| 2390 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2391 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2392 | * tty_tiocmget - get modem status |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2393 | * @tty: tty device |
| 2394 | * @file: user file pointer |
| 2395 | * @p: pointer to result |
| 2396 | * |
| 2397 | * Obtain the modem status bits from the tty driver if the feature |
| 2398 | * is supported. Return -EINVAL if it is not available. |
| 2399 | * |
| 2400 | * Locking: none (up to the driver) |
| 2401 | */ |
| 2402 | |
| 2403 | static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2404 | { |
| 2405 | int retval = -EINVAL; |
| 2406 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2407 | if (tty->ops->tiocmget) { |
| 2408 | retval = tty->ops->tiocmget(tty, file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2409 | |
| 2410 | if (retval >= 0) |
| 2411 | retval = put_user(retval, p); |
| 2412 | } |
| 2413 | return retval; |
| 2414 | } |
| 2415 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2416 | /** |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2417 | * tty_tiocmset - set modem status |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2418 | * @tty: tty device |
| 2419 | * @file: user file pointer |
| 2420 | * @cmd: command - clear bits, set bits or set all |
| 2421 | * @p: pointer to desired bits |
| 2422 | * |
| 2423 | * Set the modem status bits from the tty driver if the feature |
| 2424 | * is supported. Return -EINVAL if it is not available. |
| 2425 | * |
| 2426 | * Locking: none (up to the driver) |
| 2427 | */ |
| 2428 | |
| 2429 | static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int cmd, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2430 | unsigned __user *p) |
| 2431 | { |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2432 | int retval; |
| 2433 | unsigned int set, clear, val; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2434 | |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2435 | if (tty->ops->tiocmset == NULL) |
| 2436 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2437 | |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2438 | retval = get_user(val, p); |
| 2439 | if (retval) |
| 2440 | return retval; |
| 2441 | set = clear = 0; |
| 2442 | switch (cmd) { |
| 2443 | case TIOCMBIS: |
| 2444 | set = val; |
| 2445 | break; |
| 2446 | case TIOCMBIC: |
| 2447 | clear = val; |
| 2448 | break; |
| 2449 | case TIOCMSET: |
| 2450 | set = val; |
| 2451 | clear = ~val; |
| 2452 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2453 | } |
Alan Cox | ae67751 | 2008-07-16 21:56:54 +0100 | [diff] [blame] | 2454 | set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; |
| 2455 | clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; |
| 2456 | return tty->ops->tiocmset(tty, file, set, clear); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2457 | } |
| 2458 | |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2459 | struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) |
| 2460 | { |
| 2461 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 2462 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 2463 | tty = tty->link; |
| 2464 | return tty; |
| 2465 | } |
| 2466 | EXPORT_SYMBOL(tty_pair_get_tty); |
| 2467 | |
| 2468 | struct tty_struct *tty_pair_get_pty(struct tty_struct *tty) |
| 2469 | { |
| 2470 | if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
| 2471 | tty->driver->subtype == PTY_TYPE_MASTER) |
| 2472 | return tty; |
| 2473 | return tty->link; |
| 2474 | } |
| 2475 | EXPORT_SYMBOL(tty_pair_get_pty); |
| 2476 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2477 | /* |
| 2478 | * Split this up, as gcc can choke on it otherwise.. |
| 2479 | */ |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2480 | long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2481 | { |
| 2482 | struct tty_struct *tty, *real_tty; |
| 2483 | void __user *p = (void __user *)arg; |
| 2484 | int retval; |
| 2485 | struct tty_ldisc *ld; |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2486 | struct inode *inode = file->f_dentry->d_inode; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2487 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2488 | tty = (struct tty_struct *)file->private_data; |
| 2489 | if (tty_paranoia_check(tty, inode, "tty_ioctl")) |
| 2490 | return -EINVAL; |
| 2491 | |
Alan Cox | e8b70e7 | 2009-06-11 12:48:02 +0100 | [diff] [blame] | 2492 | real_tty = tty_pair_get_tty(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2493 | |
| 2494 | /* |
| 2495 | * Factor out some common prep work |
| 2496 | */ |
| 2497 | switch (cmd) { |
| 2498 | case TIOCSETD: |
| 2499 | case TIOCSBRK: |
| 2500 | case TIOCCBRK: |
| 2501 | case TCSBRK: |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2502 | case TCSBRKP: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2503 | retval = tty_check_change(tty); |
| 2504 | if (retval) |
| 2505 | return retval; |
| 2506 | if (cmd != TIOCCBRK) { |
| 2507 | tty_wait_until_sent(tty, 0); |
| 2508 | if (signal_pending(current)) |
| 2509 | return -EINTR; |
| 2510 | } |
| 2511 | break; |
| 2512 | } |
| 2513 | |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2514 | /* |
| 2515 | * Now do the stuff. |
| 2516 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2517 | switch (cmd) { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2518 | case TIOCSTI: |
| 2519 | return tiocsti(tty, p); |
| 2520 | case TIOCGWINSZ: |
Alan Cox | 8f52002 | 2008-10-13 10:38:46 +0100 | [diff] [blame] | 2521 | return tiocgwinsz(real_tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2522 | case TIOCSWINSZ: |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 2523 | return tiocswinsz(real_tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2524 | case TIOCCONS: |
| 2525 | return real_tty != tty ? -EINVAL : tioccons(file); |
| 2526 | case FIONBIO: |
| 2527 | return fionbio(file, p); |
| 2528 | case TIOCEXCL: |
| 2529 | set_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2530 | return 0; |
| 2531 | case TIOCNXCL: |
| 2532 | clear_bit(TTY_EXCLUSIVE, &tty->flags); |
| 2533 | return 0; |
| 2534 | case TIOCNOTTY: |
| 2535 | if (current->signal->tty != tty) |
| 2536 | return -ENOTTY; |
| 2537 | no_tty(); |
| 2538 | return 0; |
| 2539 | case TIOCSCTTY: |
| 2540 | return tiocsctty(tty, arg); |
| 2541 | case TIOCGPGRP: |
| 2542 | return tiocgpgrp(tty, real_tty, p); |
| 2543 | case TIOCSPGRP: |
| 2544 | return tiocspgrp(tty, real_tty, p); |
| 2545 | case TIOCGSID: |
| 2546 | return tiocgsid(tty, real_tty, p); |
| 2547 | case TIOCGETD: |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 2548 | return put_user(tty->ldisc->ops->num, (int __user *)p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2549 | case TIOCSETD: |
| 2550 | return tiocsetd(tty, p); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2551 | /* |
| 2552 | * Break handling |
| 2553 | */ |
| 2554 | case TIOCSBRK: /* Turn break on, unconditionally */ |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2555 | if (tty->ops->break_ctl) |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2556 | return tty->ops->break_ctl(tty, -1); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2557 | return 0; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2558 | case TIOCCBRK: /* Turn break off, unconditionally */ |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2559 | if (tty->ops->break_ctl) |
Alan Cox | 9e98966 | 2008-07-22 11:18:03 +0100 | [diff] [blame] | 2560 | return tty->ops->break_ctl(tty, 0); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2561 | return 0; |
| 2562 | case TCSBRK: /* SVID version: non-zero arg --> no break */ |
| 2563 | /* non-zero arg means wait for all output data |
| 2564 | * to be sent (performed above) but don't send break. |
| 2565 | * This is used by the tcdrain() termios function. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2566 | */ |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2567 | if (!arg) |
| 2568 | return send_break(tty, 250); |
| 2569 | return 0; |
| 2570 | case TCSBRKP: /* support for POSIX tcsendbreak() */ |
| 2571 | return send_break(tty, arg ? arg*100 : 250); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2572 | |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2573 | case TIOCMGET: |
| 2574 | return tty_tiocmget(tty, file, p); |
| 2575 | case TIOCMSET: |
| 2576 | case TIOCMBIC: |
| 2577 | case TIOCMBIS: |
| 2578 | return tty_tiocmset(tty, file, cmd, p); |
| 2579 | case TCFLSH: |
| 2580 | switch (arg) { |
| 2581 | case TCIFLUSH: |
| 2582 | case TCIOFLUSH: |
| 2583 | /* flush tty buffer and allow ldisc to process ioctl */ |
| 2584 | tty_buffer_flush(tty); |
Paul Fulghum | c5c34d4 | 2007-05-12 10:36:55 -0700 | [diff] [blame] | 2585 | break; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2586 | } |
| 2587 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2588 | } |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2589 | if (tty->ops->ioctl) { |
| 2590 | retval = (tty->ops->ioctl)(tty, file, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2591 | if (retval != -ENOIOCTLCMD) |
| 2592 | return retval; |
| 2593 | } |
| 2594 | ld = tty_ldisc_ref_wait(tty); |
| 2595 | retval = -EINVAL; |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2596 | if (ld->ops->ioctl) { |
| 2597 | retval = ld->ops->ioctl(tty, file, cmd, arg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2598 | if (retval == -ENOIOCTLCMD) |
| 2599 | retval = -EINVAL; |
| 2600 | } |
| 2601 | tty_ldisc_deref(ld); |
| 2602 | return retval; |
| 2603 | } |
| 2604 | |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2605 | #ifdef CONFIG_COMPAT |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2606 | static long tty_compat_ioctl(struct file *file, unsigned int cmd, |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2607 | unsigned long arg) |
| 2608 | { |
| 2609 | struct inode *inode = file->f_dentry->d_inode; |
| 2610 | struct tty_struct *tty = file->private_data; |
| 2611 | struct tty_ldisc *ld; |
| 2612 | int retval = -ENOIOCTLCMD; |
| 2613 | |
| 2614 | if (tty_paranoia_check(tty, inode, "tty_ioctl")) |
| 2615 | return -EINVAL; |
| 2616 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2617 | if (tty->ops->compat_ioctl) { |
| 2618 | retval = (tty->ops->compat_ioctl)(tty, file, cmd, arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2619 | if (retval != -ENOIOCTLCMD) |
| 2620 | return retval; |
| 2621 | } |
| 2622 | |
| 2623 | ld = tty_ldisc_ref_wait(tty); |
Alan Cox | a352def | 2008-07-16 21:53:12 +0100 | [diff] [blame] | 2624 | if (ld->ops->compat_ioctl) |
| 2625 | retval = ld->ops->compat_ioctl(tty, file, cmd, arg); |
Paul Fulghum | e10cc1d | 2007-05-10 22:22:50 -0700 | [diff] [blame] | 2626 | tty_ldisc_deref(ld); |
| 2627 | |
| 2628 | return retval; |
| 2629 | } |
| 2630 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2631 | |
| 2632 | /* |
| 2633 | * This implements the "Secure Attention Key" --- the idea is to |
| 2634 | * prevent trojan horses by killing all processes associated with this |
| 2635 | * tty when the user hits the "Secure Attention Key". Required for |
| 2636 | * super-paranoid applications --- see the Orange Book for more details. |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2637 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2638 | * This code could be nicer; ideally it should send a HUP, wait a few |
| 2639 | * seconds, then send a INT, and then a KILL signal. But you then |
| 2640 | * have to coordinate with the init process, since all processes associated |
| 2641 | * with the current tty must be dead before the new getty is allowed |
| 2642 | * to spawn. |
| 2643 | * |
| 2644 | * Now, if it would be correct ;-/ The current code has a nasty hole - |
| 2645 | * it doesn't catch files in flight. We may send the descriptor to ourselves |
| 2646 | * via AF_UNIX socket, close it and later fetch from socket. FIXME. |
| 2647 | * |
| 2648 | * Nasty bug: do_SAK is being called in interrupt context. This can |
| 2649 | * deadlock. We punt it up to process context. AKPM - 16Mar2001 |
| 2650 | */ |
Eric W. Biederman | 8b6312f | 2007-02-10 01:44:34 -0800 | [diff] [blame] | 2651 | void __do_SAK(struct tty_struct *tty) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2652 | { |
| 2653 | #ifdef TTY_SOFT_SAK |
| 2654 | tty_hangup(tty); |
| 2655 | #else |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2656 | struct task_struct *g, *p; |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2657 | struct pid *session; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2658 | int i; |
| 2659 | struct file *filp; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 2660 | struct fdtable *fdt; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2661 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2662 | if (!tty) |
| 2663 | return; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 2664 | session = tty->session; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2665 | |
Dan Carpenter | b3f13de | 2006-12-13 00:35:09 -0800 | [diff] [blame] | 2666 | tty_ldisc_flush(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2667 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2668 | tty_driver_flush_buffer(tty); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2669 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2670 | read_lock(&tasklist_lock); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2671 | /* Kill the entire session */ |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2672 | do_each_pid_task(session, PIDTYPE_SID, p) { |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2673 | printk(KERN_NOTICE "SAK: killed process %d" |
Oleg Nesterov | 1b0f7ff | 2009-04-02 16:58:39 -0700 | [diff] [blame] | 2674 | " (%s): task_session(p)==tty->session\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2675 | task_pid_nr(p), p->comm); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2676 | send_sig(SIGKILL, p, 1); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2677 | } while_each_pid_task(session, PIDTYPE_SID, p); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2678 | /* Now kill any processes that happen to have the |
| 2679 | * tty open. |
| 2680 | */ |
| 2681 | do_each_thread(g, p) { |
| 2682 | if (p->signal->tty == tty) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2683 | printk(KERN_NOTICE "SAK: killed process %d" |
Oleg Nesterov | 1b0f7ff | 2009-04-02 16:58:39 -0700 | [diff] [blame] | 2684 | " (%s): task_session(p)==tty->session\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2685 | task_pid_nr(p), p->comm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2686 | send_sig(SIGKILL, p, 1); |
| 2687 | continue; |
| 2688 | } |
| 2689 | task_lock(p); |
| 2690 | if (p->files) { |
Dipankar Sarma | ca99c1d | 2006-04-18 22:21:46 -0700 | [diff] [blame] | 2691 | /* |
| 2692 | * We don't take a ref to the file, so we must |
| 2693 | * hold ->file_lock instead. |
| 2694 | */ |
| 2695 | spin_lock(&p->files->file_lock); |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 2696 | fdt = files_fdtable(p->files); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2697 | for (i = 0; i < fdt->max_fds; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2698 | filp = fcheck_files(p->files, i); |
| 2699 | if (!filp) |
| 2700 | continue; |
| 2701 | if (filp->f_op->read == tty_read && |
| 2702 | filp->private_data == tty) { |
| 2703 | printk(KERN_NOTICE "SAK: killed process %d" |
| 2704 | " (%s): fd#%d opened to the tty\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2705 | task_pid_nr(p), p->comm, i); |
Eric W. Biederman | 20ac943 | 2006-04-13 04:49:07 -0600 | [diff] [blame] | 2706 | force_sig(SIGKILL, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2707 | break; |
| 2708 | } |
| 2709 | } |
Dipankar Sarma | ca99c1d | 2006-04-18 22:21:46 -0700 | [diff] [blame] | 2710 | spin_unlock(&p->files->file_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2711 | } |
| 2712 | task_unlock(p); |
Eric W. Biederman | 652486f | 2006-03-28 16:11:02 -0800 | [diff] [blame] | 2713 | } while_each_thread(g, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2714 | read_unlock(&tasklist_lock); |
| 2715 | #endif |
| 2716 | } |
| 2717 | |
Eric W. Biederman | 8b6312f | 2007-02-10 01:44:34 -0800 | [diff] [blame] | 2718 | static void do_SAK_work(struct work_struct *work) |
| 2719 | { |
| 2720 | struct tty_struct *tty = |
| 2721 | container_of(work, struct tty_struct, SAK_work); |
| 2722 | __do_SAK(tty); |
| 2723 | } |
| 2724 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2725 | /* |
| 2726 | * The tq handling here is a little racy - tty->SAK_work may already be queued. |
| 2727 | * Fortunately we don't need to worry, because if ->SAK_work is already queued, |
| 2728 | * the values which we write to it will be identical to the values which it |
| 2729 | * already has. --akpm |
| 2730 | */ |
| 2731 | void do_SAK(struct tty_struct *tty) |
| 2732 | { |
| 2733 | if (!tty) |
| 2734 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2735 | schedule_work(&tty->SAK_work); |
| 2736 | } |
| 2737 | |
| 2738 | EXPORT_SYMBOL(do_SAK); |
| 2739 | |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2740 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2741 | * initialize_tty_struct |
| 2742 | * @tty: tty to initialize |
| 2743 | * |
| 2744 | * This subroutine initializes a tty structure that has been newly |
| 2745 | * allocated. |
| 2746 | * |
| 2747 | * Locking: none - tty in question must not be exposed at this point |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2748 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2749 | |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 2750 | void initialize_tty_struct(struct tty_struct *tty, |
| 2751 | struct tty_driver *driver, int idx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2752 | { |
| 2753 | memset(tty, 0, sizeof(struct tty_struct)); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 2754 | kref_init(&tty->kref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2755 | tty->magic = TTY_MAGIC; |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 2756 | tty_ldisc_init(tty); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 2757 | tty->session = NULL; |
| 2758 | tty->pgrp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2759 | tty->overrun_time = jiffies; |
Alan Cox | 33f0f88 | 2006-01-09 20:54:13 -0800 | [diff] [blame] | 2760 | tty->buf.head = tty->buf.tail = NULL; |
| 2761 | tty_buffer_init(tty); |
Arjan van de Ven | 5785c95 | 2006-09-29 02:00:43 -0700 | [diff] [blame] | 2762 | mutex_init(&tty->termios_mutex); |
Alan Cox | c65c9bc | 2009-06-11 12:50:12 +0100 | [diff] [blame] | 2763 | mutex_init(&tty->ldisc_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2764 | init_waitqueue_head(&tty->write_wait); |
| 2765 | init_waitqueue_head(&tty->read_wait); |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 2766 | INIT_WORK(&tty->hangup_work, do_tty_hangup); |
Ingo Molnar | 70522e1 | 2006-03-23 03:00:31 -0800 | [diff] [blame] | 2767 | mutex_init(&tty->atomic_read_lock); |
| 2768 | mutex_init(&tty->atomic_write_lock); |
Joe Peterson | a88a69c | 2009-01-02 13:40:53 +0000 | [diff] [blame] | 2769 | mutex_init(&tty->output_lock); |
| 2770 | mutex_init(&tty->echo_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2771 | spin_lock_init(&tty->read_lock); |
Alan Cox | 04f378b | 2008-04-30 00:53:29 -0700 | [diff] [blame] | 2772 | spin_lock_init(&tty->ctrl_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2773 | INIT_LIST_HEAD(&tty->tty_files); |
Eric W. Biederman | 7f1f86a | 2007-02-13 14:38:58 -0700 | [diff] [blame] | 2774 | INIT_WORK(&tty->SAK_work, do_SAK_work); |
Alan Cox | bf970ee | 2008-10-13 10:42:39 +0100 | [diff] [blame] | 2775 | |
| 2776 | tty->driver = driver; |
| 2777 | tty->ops = driver->ops; |
| 2778 | tty->index = idx; |
| 2779 | tty_line_name(driver, idx, tty->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2780 | } |
| 2781 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2782 | /** |
| 2783 | * tty_put_char - write one character to a tty |
| 2784 | * @tty: tty |
| 2785 | * @ch: character |
| 2786 | * |
| 2787 | * Write one byte to the tty using the provided put_char method |
| 2788 | * if present. Returns the number of characters successfully output. |
| 2789 | * |
| 2790 | * Note: the specific put_char operation in the driver layer may go |
| 2791 | * away soon. Don't call it directly, use this method |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2792 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2793 | |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2794 | int tty_put_char(struct tty_struct *tty, unsigned char ch) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2795 | { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2796 | if (tty->ops->put_char) |
| 2797 | return tty->ops->put_char(tty, ch); |
| 2798 | return tty->ops->write(tty, &ch, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2799 | } |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2800 | EXPORT_SYMBOL_GPL(tty_put_char); |
| 2801 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 2802 | struct class *tty_class; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2803 | |
| 2804 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2805 | * tty_register_device - register a tty device |
| 2806 | * @driver: the tty driver that describes the tty device |
| 2807 | * @index: the index in the tty driver for this tty device |
| 2808 | * @device: a struct device that is associated with this tty device. |
| 2809 | * This field is optional, if there is no known struct device |
| 2810 | * for this tty device it can be set to NULL safely. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2811 | * |
Greg Kroah-Hartman | 01107d3 | 2006-08-07 22:19:37 -0700 | [diff] [blame] | 2812 | * Returns a pointer to the struct device for this tty device |
| 2813 | * (or ERR_PTR(-EFOO) on error). |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 2814 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2815 | * This call is required to be made to register an individual tty device |
| 2816 | * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If |
| 2817 | * that bit is not set, this function should not be called by a tty |
| 2818 | * driver. |
| 2819 | * |
| 2820 | * Locking: ?? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2821 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2822 | |
Greg Kroah-Hartman | 01107d3 | 2006-08-07 22:19:37 -0700 | [diff] [blame] | 2823 | struct device *tty_register_device(struct tty_driver *driver, unsigned index, |
| 2824 | struct device *device) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2825 | { |
| 2826 | char name[64]; |
| 2827 | dev_t dev = MKDEV(driver->major, driver->minor_start) + index; |
| 2828 | |
| 2829 | if (index >= driver->num) { |
| 2830 | printk(KERN_ERR "Attempt to register invalid tty line number " |
| 2831 | " (%d).\n", index); |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 2832 | return ERR_PTR(-EINVAL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2833 | } |
| 2834 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2835 | if (driver->type == TTY_DRIVER_TYPE_PTY) |
| 2836 | pty_line_name(driver, index, name); |
| 2837 | else |
| 2838 | tty_line_name(driver, index, name); |
Hansjoerg Lipp | 1cdcb6b | 2006-04-22 18:36:53 +0200 | [diff] [blame] | 2839 | |
Greg Kroah-Hartman | 03457cd | 2008-07-21 20:03:34 -0700 | [diff] [blame] | 2840 | return device_create(tty_class, device, dev, NULL, name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2841 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2842 | EXPORT_SYMBOL(tty_register_device); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2843 | |
| 2844 | /** |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2845 | * tty_unregister_device - unregister a tty device |
| 2846 | * @driver: the tty driver that describes the tty device |
| 2847 | * @index: the index in the tty driver for this tty device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2848 | * |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2849 | * If a tty device is registered with a call to tty_register_device() then |
| 2850 | * this function must be called when the tty device is gone. |
| 2851 | * |
| 2852 | * Locking: ?? |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2853 | */ |
Alan Cox | af9b897 | 2006-08-27 01:24:01 -0700 | [diff] [blame] | 2854 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2855 | void tty_unregister_device(struct tty_driver *driver, unsigned index) |
| 2856 | { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2857 | device_destroy(tty_class, |
| 2858 | MKDEV(driver->major, driver->minor_start) + index); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2859 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2860 | EXPORT_SYMBOL(tty_unregister_device); |
| 2861 | |
| 2862 | struct tty_driver *alloc_tty_driver(int lines) |
| 2863 | { |
| 2864 | struct tty_driver *driver; |
| 2865 | |
Jean Delvare | 506eb99 | 2007-07-15 23:40:14 -0700 | [diff] [blame] | 2866 | driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2867 | if (driver) { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2868 | kref_init(&driver->kref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2869 | driver->magic = TTY_DRIVER_MAGIC; |
| 2870 | driver->num = lines; |
| 2871 | /* later we'll move allocation of tables here */ |
| 2872 | } |
| 2873 | return driver; |
| 2874 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2875 | EXPORT_SYMBOL(alloc_tty_driver); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2876 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2877 | static void destruct_tty_driver(struct kref *kref) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2878 | { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2879 | struct tty_driver *driver = container_of(kref, struct tty_driver, kref); |
| 2880 | int i; |
| 2881 | struct ktermios *tp; |
| 2882 | void *p; |
| 2883 | |
| 2884 | if (driver->flags & TTY_DRIVER_INSTALLED) { |
| 2885 | /* |
| 2886 | * Free the termios and termios_locked structures because |
| 2887 | * we don't want to get memory leaks when modular tty |
| 2888 | * drivers are removed from the kernel. |
| 2889 | */ |
| 2890 | for (i = 0; i < driver->num; i++) { |
| 2891 | tp = driver->termios[i]; |
| 2892 | if (tp) { |
| 2893 | driver->termios[i] = NULL; |
| 2894 | kfree(tp); |
| 2895 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2896 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) |
| 2897 | tty_unregister_device(driver, i); |
| 2898 | } |
| 2899 | p = driver->ttys; |
| 2900 | proc_tty_unregister_driver(driver); |
| 2901 | driver->ttys = NULL; |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 2902 | driver->termios = NULL; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2903 | kfree(p); |
| 2904 | cdev_del(&driver->cdev); |
| 2905 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2906 | kfree(driver); |
| 2907 | } |
| 2908 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2909 | void tty_driver_kref_put(struct tty_driver *driver) |
| 2910 | { |
| 2911 | kref_put(&driver->kref, destruct_tty_driver); |
| 2912 | } |
| 2913 | EXPORT_SYMBOL(tty_driver_kref_put); |
| 2914 | |
Jeff Dike | b68e31d | 2006-10-02 02:17:18 -0700 | [diff] [blame] | 2915 | void tty_set_operations(struct tty_driver *driver, |
| 2916 | const struct tty_operations *op) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2917 | { |
Alan Cox | f34d7a5 | 2008-04-30 00:54:13 -0700 | [diff] [blame] | 2918 | driver->ops = op; |
| 2919 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2920 | EXPORT_SYMBOL(tty_set_operations); |
| 2921 | |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2922 | void put_tty_driver(struct tty_driver *d) |
| 2923 | { |
| 2924 | tty_driver_kref_put(d); |
| 2925 | } |
| 2926 | EXPORT_SYMBOL(put_tty_driver); |
| 2927 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2928 | /* |
| 2929 | * Called by a tty driver to register itself. |
| 2930 | */ |
| 2931 | int tty_register_driver(struct tty_driver *driver) |
| 2932 | { |
| 2933 | int error; |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2934 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2935 | dev_t dev; |
| 2936 | void **p = NULL; |
| 2937 | |
Andy Whitcroft | 543691a | 2007-05-06 14:49:33 -0700 | [diff] [blame] | 2938 | if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) { |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 2939 | p = kzalloc(driver->num * 2 * sizeof(void *), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2940 | if (!p) |
| 2941 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2942 | } |
| 2943 | |
| 2944 | if (!driver->major) { |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2945 | error = alloc_chrdev_region(&dev, driver->minor_start, |
| 2946 | driver->num, driver->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2947 | if (!error) { |
| 2948 | driver->major = MAJOR(dev); |
| 2949 | driver->minor_start = MINOR(dev); |
| 2950 | } |
| 2951 | } else { |
| 2952 | dev = MKDEV(driver->major, driver->minor_start); |
Geert Uytterhoeven | e5717c4 | 2007-02-20 15:45:21 +0100 | [diff] [blame] | 2953 | error = register_chrdev_region(dev, driver->num, driver->name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2954 | } |
| 2955 | if (error < 0) { |
| 2956 | kfree(p); |
| 2957 | return error; |
| 2958 | } |
| 2959 | |
| 2960 | if (p) { |
| 2961 | driver->ttys = (struct tty_struct **)p; |
Alan Cox | edc6afc | 2006-12-08 02:38:44 -0800 | [diff] [blame] | 2962 | driver->termios = (struct ktermios **)(p + driver->num); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2963 | } else { |
| 2964 | driver->ttys = NULL; |
| 2965 | driver->termios = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2966 | } |
| 2967 | |
| 2968 | cdev_init(&driver->cdev, &tty_fops); |
| 2969 | driver->cdev.owner = driver->owner; |
| 2970 | error = cdev_add(&driver->cdev, dev, driver->num); |
| 2971 | if (error) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2972 | unregister_chrdev_region(dev, driver->num); |
| 2973 | driver->ttys = NULL; |
Alan Cox | fe6e29f | 2008-10-13 10:44:08 +0100 | [diff] [blame] | 2974 | driver->termios = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2975 | kfree(p); |
| 2976 | return error; |
| 2977 | } |
| 2978 | |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 2979 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2980 | list_add(&driver->tty_drivers, &tty_drivers); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 2981 | mutex_unlock(&tty_mutex); |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 2982 | |
| 2983 | if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) { |
| 2984 | for (i = 0; i < driver->num; i++) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2985 | tty_register_device(driver, i, NULL); |
| 2986 | } |
| 2987 | proc_tty_register_driver(driver); |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2988 | driver->flags |= TTY_DRIVER_INSTALLED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2989 | return 0; |
| 2990 | } |
| 2991 | |
| 2992 | EXPORT_SYMBOL(tty_register_driver); |
| 2993 | |
| 2994 | /* |
| 2995 | * Called by a tty driver to unregister itself. |
| 2996 | */ |
| 2997 | int tty_unregister_driver(struct tty_driver *driver) |
| 2998 | { |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 2999 | #if 0 |
| 3000 | /* FIXME */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3001 | if (driver->refcount) |
| 3002 | return -EBUSY; |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3003 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3004 | unregister_chrdev_region(MKDEV(driver->major, driver->minor_start), |
| 3005 | driver->num); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3006 | mutex_lock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3007 | list_del(&driver->tty_drivers); |
Alexey Dobriyan | ca509f6 | 2007-05-08 00:27:12 -0700 | [diff] [blame] | 3008 | mutex_unlock(&tty_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3009 | return 0; |
| 3010 | } |
Alan Cox | 7d7b93c | 2008-10-13 10:42:09 +0100 | [diff] [blame] | 3011 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3012 | EXPORT_SYMBOL(tty_unregister_driver); |
| 3013 | |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3014 | dev_t tty_devnum(struct tty_struct *tty) |
| 3015 | { |
| 3016 | return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index; |
| 3017 | } |
| 3018 | EXPORT_SYMBOL(tty_devnum); |
| 3019 | |
| 3020 | void proc_clear_tty(struct task_struct *p) |
| 3021 | { |
Arjan van de Ven | 7c3b1dc | 2008-10-15 10:52:34 +0100 | [diff] [blame] | 3022 | unsigned long flags; |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3023 | struct tty_struct *tty; |
Arjan van de Ven | 7c3b1dc | 2008-10-15 10:52:34 +0100 | [diff] [blame] | 3024 | spin_lock_irqsave(&p->sighand->siglock, flags); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3025 | tty = p->signal->tty; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3026 | p->signal->tty = NULL; |
Arjan van de Ven | 7c3b1dc | 2008-10-15 10:52:34 +0100 | [diff] [blame] | 3027 | spin_unlock_irqrestore(&p->sighand->siglock, flags); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3028 | tty_kref_put(tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3029 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3030 | |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 3031 | /* Called under the sighand lock */ |
| 3032 | |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 3033 | 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] | 3034 | { |
| 3035 | if (tty) { |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 3036 | unsigned long flags; |
| 3037 | /* We should not have a session or pgrp to put here but.... */ |
| 3038 | spin_lock_irqsave(&tty->ctrl_lock, flags); |
Eric W. Biederman | d9c1e9a | 2007-03-18 12:45:44 -0600 | [diff] [blame] | 3039 | put_pid(tty->session); |
| 3040 | put_pid(tty->pgrp); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3041 | tty->pgrp = get_pid(task_pgrp(tsk)); |
Alan Cox | 47f8683 | 2008-04-30 00:53:30 -0700 | [diff] [blame] | 3042 | spin_unlock_irqrestore(&tty->ctrl_lock, flags); |
| 3043 | tty->session = get_pid(task_session(tsk)); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3044 | if (tsk->signal->tty) { |
| 3045 | printk(KERN_DEBUG "tty not NULL!!\n"); |
| 3046 | tty_kref_put(tsk->signal->tty); |
| 3047 | } |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3048 | } |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 3049 | put_pid(tsk->signal->tty_old_pgrp); |
Alan Cox | 9c9f4de | 2008-10-13 10:37:26 +0100 | [diff] [blame] | 3050 | tsk->signal->tty = tty_kref_get(tty); |
Eric W. Biederman | ab521dc | 2007-02-12 00:53:00 -0800 | [diff] [blame] | 3051 | tsk->signal->tty_old_pgrp = NULL; |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3052 | } |
| 3053 | |
Eric W. Biederman | 98a27ba | 2007-05-08 00:26:56 -0700 | [diff] [blame] | 3054 | 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] | 3055 | { |
| 3056 | spin_lock_irq(&tsk->sighand->siglock); |
Eric W. Biederman | 2a65f1d | 2007-05-08 00:26:53 -0700 | [diff] [blame] | 3057 | __proc_set_tty(tsk, tty); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3058 | spin_unlock_irq(&tsk->sighand->siglock); |
| 3059 | } |
| 3060 | |
| 3061 | struct tty_struct *get_current_tty(void) |
| 3062 | { |
| 3063 | struct tty_struct *tty; |
Alan Cox | 934e6eb | 2008-10-13 10:40:43 +0100 | [diff] [blame] | 3064 | unsigned long flags; |
| 3065 | |
| 3066 | spin_lock_irqsave(¤t->sighand->siglock, flags); |
Alan Cox | 452a00d | 2008-10-13 10:39:13 +0100 | [diff] [blame] | 3067 | tty = tty_kref_get(current->signal->tty); |
Alan Cox | 934e6eb | 2008-10-13 10:40:43 +0100 | [diff] [blame] | 3068 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 3069 | return tty; |
| 3070 | } |
Heiko Carstens | a311f74 | 2006-12-13 00:33:41 -0800 | [diff] [blame] | 3071 | EXPORT_SYMBOL_GPL(get_current_tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3072 | |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3073 | void tty_default_fops(struct file_operations *fops) |
| 3074 | { |
| 3075 | *fops = tty_fops; |
| 3076 | } |
| 3077 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3078 | /* |
| 3079 | * Initialize the console device. This is called *early*, so |
| 3080 | * we can't necessarily depend on lots of kernel help here. |
| 3081 | * Just do some early initializations, and do the complex setup |
| 3082 | * later. |
| 3083 | */ |
| 3084 | void __init console_init(void) |
| 3085 | { |
| 3086 | initcall_t *call; |
| 3087 | |
| 3088 | /* Setup the default TTY line discipline. */ |
Alan Cox | 01e1abb | 2008-07-22 11:16:55 +0100 | [diff] [blame] | 3089 | tty_ldisc_begin(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3090 | |
| 3091 | /* |
Alan Cox | 37bdfb0 | 2008-02-08 04:18:47 -0800 | [diff] [blame] | 3092 | * set up the console device so that later boot sequences can |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3093 | * inform about problems etc.. |
| 3094 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3095 | call = __con_initcall_start; |
| 3096 | while (call < __con_initcall_end) { |
| 3097 | (*call)(); |
| 3098 | call++; |
| 3099 | } |
| 3100 | } |
| 3101 | |
Kay Sievers | e454cea | 2009-09-18 23:01:12 +0200 | [diff] [blame] | 3102 | static char *tty_devnode(struct device *dev, mode_t *mode) |
| 3103 | { |
| 3104 | if (!mode) |
| 3105 | return NULL; |
| 3106 | if (dev->devt == MKDEV(TTYAUX_MAJOR, 0) || |
| 3107 | dev->devt == MKDEV(TTYAUX_MAJOR, 2)) |
| 3108 | *mode = 0666; |
| 3109 | return NULL; |
| 3110 | } |
| 3111 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3112 | static int __init tty_class_init(void) |
| 3113 | { |
gregkh@suse.de | 7fe845d | 2005-03-15 14:23:15 -0800 | [diff] [blame] | 3114 | tty_class = class_create(THIS_MODULE, "tty"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3115 | if (IS_ERR(tty_class)) |
| 3116 | return PTR_ERR(tty_class); |
Kay Sievers | e454cea | 2009-09-18 23:01:12 +0200 | [diff] [blame] | 3117 | tty_class->devnode = tty_devnode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3118 | return 0; |
| 3119 | } |
| 3120 | |
| 3121 | postcore_initcall(tty_class_init); |
| 3122 | |
| 3123 | /* 3/2004 jmc: why do these devices exist? */ |
| 3124 | |
| 3125 | static struct cdev tty_cdev, console_cdev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3126 | |
| 3127 | /* |
| 3128 | * Ok, now we can initialize the rest of the tty devices and can count |
| 3129 | * on memory allocations, interrupts etc.. |
| 3130 | */ |
| 3131 | static int __init tty_init(void) |
| 3132 | { |
| 3133 | cdev_init(&tty_cdev, &tty_fops); |
| 3134 | if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) || |
| 3135 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0) |
| 3136 | panic("Couldn't register /dev/tty driver\n"); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3137 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, |
Greg Kroah-Hartman | 47aa579 | 2008-05-21 12:52:33 -0700 | [diff] [blame] | 3138 | "tty"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3139 | |
| 3140 | cdev_init(&console_cdev, &console_fops); |
| 3141 | if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) || |
| 3142 | register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0) |
| 3143 | panic("Couldn't register /dev/console driver\n"); |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3144 | device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL, |
Greg Kroah-Hartman | 47aa579 | 2008-05-21 12:52:33 -0700 | [diff] [blame] | 3145 | "console"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3146 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3147 | #ifdef CONFIG_VT |
Alan Cox | d81ed10 | 2008-10-13 10:41:42 +0100 | [diff] [blame] | 3148 | vty_init(&console_fops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3149 | #endif |
| 3150 | return 0; |
| 3151 | } |
| 3152 | module_init(tty_init); |