Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM |
| 3 | * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM |
| 4 | * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp. |
| 5 | * Copyright (C) 2004 IBM Corporation |
| 6 | * |
| 7 | * Additional Author(s): |
| 8 | * Ryan S. Arnold <rsa@us.ibm.com> |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation; either version 2 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | * GNU General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License |
| 21 | * along with this program; if not, write to the Free Software |
| 22 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 23 | */ |
| 24 | |
| 25 | #include <linux/console.h> |
| 26 | #include <linux/cpumask.h> |
| 27 | #include <linux/init.h> |
| 28 | #include <linux/kbd_kern.h> |
| 29 | #include <linux/kernel.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <linux/kthread.h> |
| 31 | #include <linux/list.h> |
| 32 | #include <linux/module.h> |
| 33 | #include <linux/major.h> |
Paul Gortmaker | f76a1cb | 2014-01-14 16:03:37 -0500 | [diff] [blame] | 34 | #include <linux/atomic.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #include <linux/sysrq.h> |
| 36 | #include <linux/tty.h> |
| 37 | #include <linux/tty_flip.h> |
| 38 | #include <linux/sched.h> |
| 39 | #include <linux/spinlock.h> |
| 40 | #include <linux/delay.h> |
Nigel Cunningham | 7dfb710 | 2006-12-06 20:34:23 -0800 | [diff] [blame] | 41 | #include <linux/freezer.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 42 | #include <linux/slab.h> |
Anton Blanchard | 762e77a | 2011-07-12 19:44:05 +0000 | [diff] [blame] | 43 | #include <linux/serial_core.h> |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 44 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | #include <asm/uaccess.h> |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 46 | |
| 47 | #include "hvc_console.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | |
| 49 | #define HVC_MAJOR 229 |
| 50 | #define HVC_MINOR 0 |
| 51 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | /* |
| 53 | * Wait this long per iteration while trying to push buffered data to the |
| 54 | * hypervisor before allowing the tty to complete a close operation. |
| 55 | */ |
| 56 | #define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */ |
| 57 | |
| 58 | /* |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 59 | * These sizes are most efficient for vio, because they are the |
| 60 | * native transfer size. We could make them selectable in the |
| 61 | * future to better deal with backends that want other buffer sizes. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | #define N_OUTBUF 16 |
| 64 | #define N_INBUF 16 |
| 65 | |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 66 | #define __ALIGNED__ __attribute__((__aligned__(sizeof(long)))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 68 | static struct tty_driver *hvc_driver; |
| 69 | static struct task_struct *hvc_task; |
| 70 | |
| 71 | /* Picks up late kicks after list walk but before schedule() */ |
| 72 | static int hvc_kicked; |
| 73 | |
Paul Gortmaker | f76a1cb | 2014-01-14 16:03:37 -0500 | [diff] [blame] | 74 | /* hvc_init is triggered from hvc_alloc, i.e. only when actually used */ |
| 75 | static atomic_t hvc_needs_init __read_mostly = ATOMIC_INIT(-1); |
| 76 | |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 77 | static int hvc_init(void); |
| 78 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 79 | #ifdef CONFIG_MAGIC_SYSRQ |
| 80 | static int sysrq_pressed; |
| 81 | #endif |
| 82 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | /* dynamic list of hvc_struct instances */ |
Denis Cheng | bed9759 | 2008-02-06 01:37:35 -0800 | [diff] [blame] | 84 | static LIST_HEAD(hvc_structs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | |
| 86 | /* |
| 87 | * Protect the list of hvc_struct instances from inserts and removals during |
| 88 | * list traversal. |
| 89 | */ |
| 90 | static DEFINE_SPINLOCK(hvc_structs_lock); |
| 91 | |
| 92 | /* |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 93 | * This value is used to assign a tty->index value to a hvc_struct based |
| 94 | * upon order of exposure via hvc_probe(), when we can not match it to |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 95 | * a console candidate registered with hvc_instantiate(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | */ |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 97 | static int last_hvc = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | /* |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 100 | * Do not call this function with either the hvc_structs_lock or the hvc_struct |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 101 | * lock held. If successful, this function increments the kref reference |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | * count against the target hvc_struct so it should be released when finished. |
| 103 | */ |
Adrian Bunk | 4fa156e | 2007-05-08 00:24:24 -0700 | [diff] [blame] | 104 | static struct hvc_struct *hvc_get_by_index(int index) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | { |
| 106 | struct hvc_struct *hp; |
| 107 | unsigned long flags; |
| 108 | |
| 109 | spin_lock(&hvc_structs_lock); |
| 110 | |
| 111 | list_for_each_entry(hp, &hvc_structs, next) { |
| 112 | spin_lock_irqsave(&hp->lock, flags); |
| 113 | if (hp->index == index) { |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 114 | tty_port_get(&hp->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | spin_unlock_irqrestore(&hp->lock, flags); |
| 116 | spin_unlock(&hvc_structs_lock); |
| 117 | return hp; |
| 118 | } |
| 119 | spin_unlock_irqrestore(&hp->lock, flags); |
| 120 | } |
| 121 | hp = NULL; |
| 122 | |
| 123 | spin_unlock(&hvc_structs_lock); |
| 124 | return hp; |
| 125 | } |
| 126 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 127 | |
| 128 | /* |
| 129 | * Initial console vtermnos for console API usage prior to full console |
| 130 | * initialization. Any vty adapter outside this range will not have usable |
| 131 | * console interfaces but can still be used as a tty device. This has to be |
| 132 | * static because kmalloc will not work during early console init. |
| 133 | */ |
Rusty Russell | b511306 | 2010-01-18 03:44:57 +0000 | [diff] [blame] | 134 | static const struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES]; |
Milton Miller | 64e4da5 | 2005-07-07 17:56:22 -0700 | [diff] [blame] | 135 | static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] = |
| 136 | {[0 ... MAX_NR_HVC_CONSOLES - 1] = -1}; |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 137 | |
| 138 | /* |
| 139 | * Console APIs, NOT TTY. These APIs are available immediately when |
| 140 | * hvc_console_setup() finds adapters. |
| 141 | */ |
| 142 | |
Adrian Bunk | 4fa156e | 2007-05-08 00:24:24 -0700 | [diff] [blame] | 143 | static void hvc_console_print(struct console *co, const char *b, |
| 144 | unsigned count) |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 145 | { |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 146 | char c[N_OUTBUF] __ALIGNED__; |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 147 | unsigned i = 0, n = 0; |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 148 | int r, donecr = 0, index = co->index; |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 149 | |
| 150 | /* Console access attempt outside of acceptable console range. */ |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 151 | if (index >= MAX_NR_HVC_CONSOLES) |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 152 | return; |
| 153 | |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 154 | /* This console adapter was removed so it is not usable. */ |
Roel Kluin | ecfcbee | 2009-12-09 12:34:16 -0800 | [diff] [blame] | 155 | if (vtermnos[index] == -1) |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 156 | return; |
| 157 | |
| 158 | while (count > 0 || i > 0) { |
| 159 | if (count > 0 && i < sizeof(c)) { |
| 160 | if (b[n] == '\n' && !donecr) { |
| 161 | c[i++] = '\r'; |
| 162 | donecr = 1; |
| 163 | } else { |
| 164 | c[i++] = b[n++]; |
| 165 | donecr = 0; |
| 166 | --count; |
| 167 | } |
| 168 | } else { |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 169 | r = cons_ops[index]->put_chars(vtermnos[index], c, i); |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 170 | if (r <= 0) { |
Hendrik Brueckner | 8c2381a | 2011-07-05 21:50:18 +0000 | [diff] [blame] | 171 | /* throw away characters on error |
| 172 | * but spin in case of -EAGAIN */ |
| 173 | if (r != -EAGAIN) |
| 174 | i = 0; |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 175 | } else if (r > 0) { |
| 176 | i -= r; |
| 177 | if (i > 0) |
| 178 | memmove(c, c+r, i); |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | } |
| 183 | |
| 184 | static struct tty_driver *hvc_console_device(struct console *c, int *index) |
| 185 | { |
Milton Miller | 7805b1b | 2005-07-07 17:56:23 -0700 | [diff] [blame] | 186 | if (vtermnos[c->index] == -1) |
| 187 | return NULL; |
| 188 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 189 | *index = c->index; |
| 190 | return hvc_driver; |
| 191 | } |
| 192 | |
Tomoki Sekiyama | 501fed4 | 2014-05-02 18:58:24 -0400 | [diff] [blame] | 193 | static int hvc_console_setup(struct console *co, char *options) |
Benjamin Herrenschmidt | 4d2bb3f | 2011-05-12 13:46:38 +1000 | [diff] [blame] | 194 | { |
Milton Miller | 7805b1b | 2005-07-07 17:56:23 -0700 | [diff] [blame] | 195 | if (co->index < 0 || co->index >= MAX_NR_HVC_CONSOLES) |
| 196 | return -ENODEV; |
| 197 | |
| 198 | if (vtermnos[co->index] == -1) |
| 199 | return -ENODEV; |
| 200 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 201 | return 0; |
| 202 | } |
| 203 | |
Chris Metcalf | 4455b11 | 2010-07-06 08:03:16 +0000 | [diff] [blame] | 204 | static struct console hvc_console = { |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 205 | .name = "hvc", |
| 206 | .write = hvc_console_print, |
| 207 | .device = hvc_console_device, |
| 208 | .setup = hvc_console_setup, |
| 209 | .flags = CON_PRINTBUFFER, |
| 210 | .index = -1, |
| 211 | }; |
| 212 | |
Milton Miller | d5ee257 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 213 | /* |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 214 | * Early console initialization. Precedes driver initialization. |
Milton Miller | d5ee257 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 215 | * |
| 216 | * (1) we are first, and the user specified another driver |
| 217 | * -- index will remain -1 |
| 218 | * (2) we are first and the user specified no driver |
| 219 | * -- index will be set to 0, then we will fail setup. |
| 220 | * (3) we are first and the user specified our driver |
| 221 | * -- index will be set to user specified driver, and we will fail |
| 222 | * (4) we are after driver, and this initcall will register us |
| 223 | * -- if the user didn't specify a driver then the console will match |
| 224 | * |
| 225 | * Note that for cases 2 and 3, we will match later when the io driver |
| 226 | * calls hvc_instantiate() and call register again. |
| 227 | */ |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 228 | static int __init hvc_console_init(void) |
| 229 | { |
Chris Metcalf | 4455b11 | 2010-07-06 08:03:16 +0000 | [diff] [blame] | 230 | register_console(&hvc_console); |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 231 | return 0; |
| 232 | } |
| 233 | console_initcall(hvc_console_init); |
| 234 | |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 235 | /* callback when the kboject ref count reaches zero. */ |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 236 | static void hvc_port_destruct(struct tty_port *port) |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 237 | { |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 238 | struct hvc_struct *hp = container_of(port, struct hvc_struct, port); |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 239 | unsigned long flags; |
| 240 | |
| 241 | spin_lock(&hvc_structs_lock); |
| 242 | |
| 243 | spin_lock_irqsave(&hp->lock, flags); |
| 244 | list_del(&(hp->next)); |
| 245 | spin_unlock_irqrestore(&hp->lock, flags); |
| 246 | |
| 247 | spin_unlock(&hvc_structs_lock); |
| 248 | |
| 249 | kfree(hp); |
| 250 | } |
| 251 | |
Benjamin Herrenschmidt | 92057a4 | 2012-07-23 21:33:13 +0000 | [diff] [blame] | 252 | static void hvc_check_console(int index) |
| 253 | { |
| 254 | /* Already enabled, bail out */ |
| 255 | if (hvc_console.flags & CON_ENABLED) |
| 256 | return; |
| 257 | |
| 258 | /* If this index is what the user requested, then register |
| 259 | * now (setup won't fail at this point). It's ok to just |
| 260 | * call register again if previously .setup failed. |
| 261 | */ |
| 262 | if (index == hvc_console.index) |
| 263 | register_console(&hvc_console); |
| 264 | } |
| 265 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 266 | /* |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 267 | * hvc_instantiate() is an early console discovery method which locates |
| 268 | * consoles * prior to the vio subsystem discovering them. Hotplugged |
| 269 | * vty adapters do NOT get an hvc_instantiate() callback since they |
| 270 | * appear after early console init. |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 271 | */ |
Rusty Russell | b511306 | 2010-01-18 03:44:57 +0000 | [diff] [blame] | 272 | int hvc_instantiate(uint32_t vtermno, int index, const struct hv_ops *ops) |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 273 | { |
Milton Miller | 7805b1b | 2005-07-07 17:56:23 -0700 | [diff] [blame] | 274 | struct hvc_struct *hp; |
| 275 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 276 | if (index < 0 || index >= MAX_NR_HVC_CONSOLES) |
| 277 | return -1; |
| 278 | |
| 279 | if (vtermnos[index] != -1) |
| 280 | return -1; |
| 281 | |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 282 | /* make sure no no tty has been registered in this index */ |
Milton Miller | 7805b1b | 2005-07-07 17:56:23 -0700 | [diff] [blame] | 283 | hp = hvc_get_by_index(index); |
| 284 | if (hp) { |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 285 | tty_port_put(&hp->port); |
Milton Miller | 7805b1b | 2005-07-07 17:56:23 -0700 | [diff] [blame] | 286 | return -1; |
| 287 | } |
| 288 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 289 | vtermnos[index] = vtermno; |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 290 | cons_ops[index] = ops; |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 291 | |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 292 | /* reserve all indices up to and including this index */ |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 293 | if (last_hvc < index) |
| 294 | last_hvc = index; |
| 295 | |
Benjamin Herrenschmidt | 92057a4 | 2012-07-23 21:33:13 +0000 | [diff] [blame] | 296 | /* check if we need to re-register the kernel console */ |
| 297 | hvc_check_console(index); |
Milton Miller | d5ee257 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 298 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 299 | return 0; |
| 300 | } |
Christian Borntraeger | 7721c49 | 2008-07-25 12:06:06 -0500 | [diff] [blame] | 301 | EXPORT_SYMBOL_GPL(hvc_instantiate); |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 302 | |
| 303 | /* Wake the sleeping khvcd */ |
Christian Borntraeger | 611e097 | 2008-06-20 15:24:08 +0200 | [diff] [blame] | 304 | void hvc_kick(void) |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 305 | { |
| 306 | hvc_kicked = 1; |
| 307 | wake_up_process(hvc_task); |
| 308 | } |
Christian Borntraeger | 7721c49 | 2008-07-25 12:06:06 -0500 | [diff] [blame] | 309 | EXPORT_SYMBOL_GPL(hvc_kick); |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 310 | |
Milton Miller | 837dcfa | 2005-07-07 17:56:16 -0700 | [diff] [blame] | 311 | static void hvc_unthrottle(struct tty_struct *tty) |
| 312 | { |
| 313 | hvc_kick(); |
| 314 | } |
| 315 | |
Jiri Slaby | bdb498c | 2012-08-07 21:48:04 +0200 | [diff] [blame] | 316 | static int hvc_install(struct tty_driver *driver, struct tty_struct *tty) |
| 317 | { |
| 318 | struct hvc_struct *hp; |
| 319 | int rc; |
| 320 | |
| 321 | /* Auto increments kref reference if found. */ |
| 322 | if (!(hp = hvc_get_by_index(tty->index))) |
| 323 | return -ENODEV; |
| 324 | |
| 325 | tty->driver_data = hp; |
| 326 | |
| 327 | rc = tty_port_install(&hp->port, driver, tty); |
| 328 | if (rc) |
| 329 | tty_port_put(&hp->port); |
| 330 | return rc; |
| 331 | } |
| 332 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | /* |
| 334 | * The TTY interface won't be used until after the vio layer has exposed the vty |
| 335 | * adapter to the kernel. |
| 336 | */ |
| 337 | static int hvc_open(struct tty_struct *tty, struct file * filp) |
| 338 | { |
Jiri Slaby | bdb498c | 2012-08-07 21:48:04 +0200 | [diff] [blame] | 339 | struct hvc_struct *hp = tty->driver_data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | int rc = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 343 | spin_lock_irqsave(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | /* Check and then increment for fast path open. */ |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 345 | if (hp->port.count++ > 0) { |
| 346 | spin_unlock_irqrestore(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | hvc_kick(); |
| 348 | return 0; |
| 349 | } /* else count == 0 */ |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 350 | spin_unlock_irqrestore(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 352 | tty_port_tty_set(&hp->port, tty); |
| 353 | |
Christian Borntraeger | b1b135c | 2008-08-07 09:18:34 +0200 | [diff] [blame] | 354 | if (hp->ops->notifier_add) |
| 355 | rc = hp->ops->notifier_add(hp, hp->data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | |
| 357 | /* |
Christian Borntraeger | 611e097 | 2008-06-20 15:24:08 +0200 | [diff] [blame] | 358 | * If the notifier fails we return an error. The tty layer |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 359 | * will call hvc_close() after a failed open but we don't want to clean |
| 360 | * up there so we'll clean up here and clear out the previously set |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 361 | * tty fields and return the kref reference. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | */ |
| 363 | if (rc) { |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 364 | tty_port_tty_set(&hp->port, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | tty->driver_data = NULL; |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 366 | tty_port_put(&hp->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc); |
Hendrik Brueckner | 33e745a | 2013-07-02 17:07:14 +0200 | [diff] [blame] | 368 | } else |
| 369 | /* We are ready... raise DTR/RTS */ |
| 370 | if (C_BAUD(tty)) |
| 371 | if (hp->ops->dtr_rts) |
| 372 | hp->ops->dtr_rts(hp, 1); |
| 373 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | /* Force wakeup of the polling thread */ |
| 375 | hvc_kick(); |
| 376 | |
| 377 | return rc; |
| 378 | } |
| 379 | |
| 380 | static void hvc_close(struct tty_struct *tty, struct file * filp) |
| 381 | { |
| 382 | struct hvc_struct *hp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | unsigned long flags; |
| 384 | |
| 385 | if (tty_hung_up_p(filp)) |
| 386 | return; |
| 387 | |
| 388 | /* |
| 389 | * No driver_data means that this close was issued after a failed |
| 390 | * hvc_open by the tty layer's release_dev() function and we can just |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 391 | * exit cleanly because the kref reference wasn't made. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | */ |
| 393 | if (!tty->driver_data) |
| 394 | return; |
| 395 | |
| 396 | hp = tty->driver_data; |
Amit Shah | e74d098 | 2010-03-12 11:53:15 +0530 | [diff] [blame] | 397 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 398 | spin_lock_irqsave(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 400 | if (--hp->port.count == 0) { |
| 401 | spin_unlock_irqrestore(&hp->port.lock, flags); |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 402 | /* We are done with the tty pointer now. */ |
| 403 | tty_port_tty_set(&hp->port, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | |
Hendrik Brueckner | 33e745a | 2013-07-02 17:07:14 +0200 | [diff] [blame] | 405 | if (C_HUPCL(tty)) |
| 406 | if (hp->ops->dtr_rts) |
| 407 | hp->ops->dtr_rts(hp, 0); |
| 408 | |
Christian Borntraeger | eef2622 | 2008-10-12 21:51:31 +0000 | [diff] [blame] | 409 | if (hp->ops->notifier_del) |
| 410 | hp->ops->notifier_del(hp, hp->data); |
| 411 | |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 412 | /* cancel pending tty resize work */ |
| 413 | cancel_work_sync(&hp->tty_resize); |
| 414 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | /* |
| 416 | * Chain calls chars_in_buffer() and returns immediately if |
| 417 | * there is no buffered data otherwise sleeps on a wait queue |
| 418 | * waking periodically to check chars_in_buffer(). |
| 419 | */ |
Jiri Slaby | 0b05835 | 2011-08-25 15:12:08 +0200 | [diff] [blame] | 420 | tty_wait_until_sent_from_close(tty, HVC_CLOSE_WAIT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | } else { |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 422 | if (hp->port.count < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | printk(KERN_ERR "hvc_close %X: oops, count is %d\n", |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 424 | hp->vtermno, hp->port.count); |
| 425 | spin_unlock_irqrestore(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | } |
Jiri Slaby | bdb498c | 2012-08-07 21:48:04 +0200 | [diff] [blame] | 427 | } |
| 428 | |
| 429 | static void hvc_cleanup(struct tty_struct *tty) |
| 430 | { |
| 431 | struct hvc_struct *hp = tty->driver_data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 433 | tty_port_put(&hp->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | } |
| 435 | |
| 436 | static void hvc_hangup(struct tty_struct *tty) |
| 437 | { |
| 438 | struct hvc_struct *hp = tty->driver_data; |
| 439 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | |
| 441 | if (!hp) |
| 442 | return; |
| 443 | |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 444 | /* cancel pending tty resize work */ |
| 445 | cancel_work_sync(&hp->tty_resize); |
| 446 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 447 | spin_lock_irqsave(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | |
| 449 | /* |
| 450 | * The N_TTY line discipline has problems such that in a close vs |
| 451 | * open->hangup case this can be called after the final close so prevent |
| 452 | * that from happening for now. |
| 453 | */ |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 454 | if (hp->port.count <= 0) { |
| 455 | spin_unlock_irqrestore(&hp->port.lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | return; |
| 457 | } |
| 458 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 459 | hp->port.count = 0; |
| 460 | spin_unlock_irqrestore(&hp->port.lock, flags); |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 461 | tty_port_tty_set(&hp->port, NULL); |
Christian Borntraeger | eef2622 | 2008-10-12 21:51:31 +0000 | [diff] [blame] | 462 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 463 | hp->n_outbuf = 0; |
| 464 | |
Hendrik Brueckner | fc362e2 | 2008-10-13 23:12:48 +0000 | [diff] [blame] | 465 | if (hp->ops->notifier_hangup) |
Amit Shah | e74d098 | 2010-03-12 11:53:15 +0530 | [diff] [blame] | 466 | hp->ops->notifier_hangup(hp, hp->data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | } |
| 468 | |
| 469 | /* |
| 470 | * Push buffered characters whether they were just recently buffered or waiting |
| 471 | * on a blocked hypervisor. Call this function with hp->lock held. |
| 472 | */ |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 473 | static int hvc_push(struct hvc_struct *hp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | { |
| 475 | int n; |
| 476 | |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 477 | n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | if (n <= 0) { |
Hendrik Brueckner | 8c2381a | 2011-07-05 21:50:18 +0000 | [diff] [blame] | 479 | if (n == 0 || n == -EAGAIN) { |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 480 | hp->do_wakeup = 1; |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 481 | return 0; |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 482 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | /* throw away output on error; this happens when |
| 484 | there is no session connected to the vterm. */ |
| 485 | hp->n_outbuf = 0; |
| 486 | } else |
| 487 | hp->n_outbuf -= n; |
| 488 | if (hp->n_outbuf > 0) |
| 489 | memmove(hp->outbuf, hp->outbuf + n, hp->n_outbuf); |
| 490 | else |
| 491 | hp->do_wakeup = 1; |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 492 | |
| 493 | return n; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | } |
| 495 | |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 496 | static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | { |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 498 | struct hvc_struct *hp = tty->driver_data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | unsigned long flags; |
| 500 | int rsize, written = 0; |
| 501 | |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 502 | /* This write was probably executed during a tty close. */ |
| 503 | if (!hp) |
| 504 | return -EPIPE; |
| 505 | |
Jiri Slaby | 0146b69 | 2012-04-02 13:54:23 +0200 | [diff] [blame] | 506 | /* FIXME what's this (unprotected) check for? */ |
| 507 | if (hp->port.count <= 0) |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 508 | return -EIO; |
| 509 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | spin_lock_irqsave(&hp->lock, flags); |
| 511 | |
| 512 | /* Push pending writes */ |
| 513 | if (hp->n_outbuf > 0) |
| 514 | hvc_push(hp); |
| 515 | |
Stephen Rothwell | 4e9e95a | 2006-07-13 18:53:32 +1000 | [diff] [blame] | 516 | while (count > 0 && (rsize = hp->outbuf_size - hp->n_outbuf) > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | if (rsize > count) |
| 518 | rsize = count; |
| 519 | memcpy(hp->outbuf + hp->n_outbuf, buf, rsize); |
| 520 | count -= rsize; |
| 521 | buf += rsize; |
| 522 | hp->n_outbuf += rsize; |
| 523 | written += rsize; |
| 524 | hvc_push(hp); |
| 525 | } |
| 526 | spin_unlock_irqrestore(&hp->lock, flags); |
| 527 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | /* |
| 529 | * Racy, but harmless, kick thread if there is still pending data. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 530 | */ |
| 531 | if (hp->n_outbuf) |
| 532 | hvc_kick(); |
| 533 | |
| 534 | return written; |
| 535 | } |
| 536 | |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 537 | /** |
| 538 | * hvc_set_winsz() - Resize the hvc tty terminal window. |
| 539 | * @work: work structure. |
| 540 | * |
| 541 | * The routine shall not be called within an atomic context because it |
| 542 | * might sleep. |
| 543 | * |
| 544 | * Locking: hp->lock |
| 545 | */ |
| 546 | static void hvc_set_winsz(struct work_struct *work) |
| 547 | { |
| 548 | struct hvc_struct *hp; |
| 549 | unsigned long hvc_flags; |
| 550 | struct tty_struct *tty; |
| 551 | struct winsize ws; |
| 552 | |
| 553 | hp = container_of(work, struct hvc_struct, tty_resize); |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 554 | |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 555 | tty = tty_port_tty_get(&hp->port); |
| 556 | if (!tty) |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 557 | return; |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 558 | |
| 559 | spin_lock_irqsave(&hp->lock, hvc_flags); |
| 560 | ws = hp->ws; |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 561 | spin_unlock_irqrestore(&hp->lock, hvc_flags); |
| 562 | |
Alan Cox | fc6f623 | 2009-01-02 13:43:17 +0000 | [diff] [blame] | 563 | tty_do_resize(tty, &ws); |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 564 | tty_kref_put(tty); |
| 565 | } |
| 566 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | /* |
| 568 | * This is actually a contract between the driver and the tty layer outlining |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 569 | * how much write room the driver can guarantee will be sent OR BUFFERED. This |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | * driver MUST honor the return value. |
| 571 | */ |
| 572 | static int hvc_write_room(struct tty_struct *tty) |
| 573 | { |
| 574 | struct hvc_struct *hp = tty->driver_data; |
| 575 | |
| 576 | if (!hp) |
Alan Cox | d83114e | 2012-09-17 12:03:39 +0100 | [diff] [blame] | 577 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | |
Stephen Rothwell | 4e9e95a | 2006-07-13 18:53:32 +1000 | [diff] [blame] | 579 | return hp->outbuf_size - hp->n_outbuf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | } |
| 581 | |
| 582 | static int hvc_chars_in_buffer(struct tty_struct *tty) |
| 583 | { |
| 584 | struct hvc_struct *hp = tty->driver_data; |
| 585 | |
| 586 | if (!hp) |
Alan Cox | 23198fd | 2009-07-20 16:05:27 +0100 | [diff] [blame] | 587 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | return hp->n_outbuf; |
| 589 | } |
| 590 | |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 591 | /* |
| 592 | * timeout will vary between the MIN and MAX values defined here. By default |
| 593 | * and during console activity we will use a default MIN_TIMEOUT of 10. When |
| 594 | * the console is idle, we increase the timeout value on each pass through |
| 595 | * msleep until we reach the max. This may be noticeable as a brief (average |
| 596 | * one second) delay on the console before the console responds to input when |
| 597 | * there has been no input for some time. |
| 598 | */ |
| 599 | #define MIN_TIMEOUT (10) |
| 600 | #define MAX_TIMEOUT (2000) |
| 601 | static u32 timeout = MIN_TIMEOUT; |
| 602 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 603 | #define HVC_POLL_READ 0x00000001 |
| 604 | #define HVC_POLL_WRITE 0x00000002 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | |
Christian Borntraeger | 611e097 | 2008-06-20 15:24:08 +0200 | [diff] [blame] | 606 | int hvc_poll(struct hvc_struct *hp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | { |
| 608 | struct tty_struct *tty; |
| 609 | int i, n, poll_mask = 0; |
| 610 | char buf[N_INBUF] __ALIGNED__; |
| 611 | unsigned long flags; |
| 612 | int read_total = 0; |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 613 | int written_total = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | |
| 615 | spin_lock_irqsave(&hp->lock, flags); |
| 616 | |
| 617 | /* Push pending writes */ |
| 618 | if (hp->n_outbuf > 0) |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 619 | written_total = hvc_push(hp); |
Michael Ellerman | b537446 | 2006-06-07 17:10:03 +1000 | [diff] [blame] | 620 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | /* Reschedule us if still some write pending */ |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 622 | if (hp->n_outbuf > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | poll_mask |= HVC_POLL_WRITE; |
Hendrik Brueckner | 3feebbb | 2008-10-13 23:12:50 +0000 | [diff] [blame] | 624 | /* If hvc_push() was not able to write, sleep a few msecs */ |
| 625 | timeout = (written_total) ? 0 : MIN_TIMEOUT; |
| 626 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | |
| 628 | /* No tty attached, just skip */ |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 629 | tty = tty_port_tty_get(&hp->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 630 | if (tty == NULL) |
| 631 | goto bail; |
| 632 | |
| 633 | /* Now check if we can get data (are we throttled ?) */ |
| 634 | if (test_bit(TTY_THROTTLED, &tty->flags)) |
| 635 | goto throttled; |
| 636 | |
Christian Borntraeger | 611e097 | 2008-06-20 15:24:08 +0200 | [diff] [blame] | 637 | /* If we aren't notifier driven and aren't throttled, we always |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | * request a reschedule |
| 639 | */ |
Christian Borntraeger | 611e097 | 2008-06-20 15:24:08 +0200 | [diff] [blame] | 640 | if (!hp->irq_requested) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | poll_mask |= HVC_POLL_READ; |
| 642 | |
| 643 | /* Read data if any */ |
| 644 | for (;;) { |
Jiri Slaby | 227434f | 2013-01-03 15:53:01 +0100 | [diff] [blame] | 645 | int count = tty_buffer_request_room(&hp->port, N_INBUF); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 646 | |
| 647 | /* If flip is full, just reschedule a later read */ |
| 648 | if (count == 0) { |
| 649 | poll_mask |= HVC_POLL_READ; |
| 650 | break; |
| 651 | } |
| 652 | |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 653 | n = hp->ops->get_chars(hp->vtermno, buf, count); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 654 | if (n <= 0) { |
| 655 | /* Hangup the tty when disconnected from host */ |
| 656 | if (n == -EPIPE) { |
| 657 | spin_unlock_irqrestore(&hp->lock, flags); |
| 658 | tty_hangup(tty); |
| 659 | spin_lock_irqsave(&hp->lock, flags); |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 660 | } else if ( n == -EAGAIN ) { |
| 661 | /* |
| 662 | * Some back-ends can only ensure a certain min |
| 663 | * num of bytes read, which may be > 'count'. |
| 664 | * Let the tty clear the flip buff to make room. |
| 665 | */ |
| 666 | poll_mask |= HVC_POLL_READ; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | } |
| 668 | break; |
| 669 | } |
| 670 | for (i = 0; i < n; ++i) { |
| 671 | #ifdef CONFIG_MAGIC_SYSRQ |
Chris Metcalf | 4455b11 | 2010-07-06 08:03:16 +0000 | [diff] [blame] | 672 | if (hp->index == hvc_console.index) { |
Milton Miller | 2b9e0ba | 2005-07-07 17:56:19 -0700 | [diff] [blame] | 673 | /* Handle the SysRq Hack */ |
| 674 | /* XXX should support a sequence */ |
| 675 | if (buf[i] == '\x0f') { /* ^O */ |
Hendrik Brueckner | 368c1e3 | 2008-12-16 00:09:38 +0000 | [diff] [blame] | 676 | /* if ^O is pressed again, reset |
| 677 | * sysrq_pressed and flip ^O char */ |
| 678 | sysrq_pressed = !sysrq_pressed; |
| 679 | if (sysrq_pressed) |
| 680 | continue; |
Milton Miller | 2b9e0ba | 2005-07-07 17:56:19 -0700 | [diff] [blame] | 681 | } else if (sysrq_pressed) { |
Dmitry Torokhov | f335397 | 2010-08-17 21:15:47 -0700 | [diff] [blame] | 682 | handle_sysrq(buf[i]); |
Milton Miller | 2b9e0ba | 2005-07-07 17:56:19 -0700 | [diff] [blame] | 683 | sysrq_pressed = 0; |
| 684 | continue; |
| 685 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | } |
| 687 | #endif /* CONFIG_MAGIC_SYSRQ */ |
Jiri Slaby | 92a19f9 | 2013-01-03 15:53:03 +0100 | [diff] [blame] | 688 | tty_insert_flip_char(&hp->port, buf[i], 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | } |
| 690 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | read_total += n; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | } |
| 693 | throttled: |
| 694 | /* Wakeup write queue if necessary */ |
| 695 | if (hp->do_wakeup) { |
| 696 | hp->do_wakeup = 0; |
| 697 | tty_wakeup(tty); |
| 698 | } |
| 699 | bail: |
| 700 | spin_unlock_irqrestore(&hp->lock, flags); |
| 701 | |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 702 | if (read_total) { |
| 703 | /* Activity is occurring, so reset the polling backoff value to |
| 704 | a minimum for performance. */ |
| 705 | timeout = MIN_TIMEOUT; |
| 706 | |
Jiri Slaby | 2e124b4 | 2013-01-03 15:53:06 +0100 | [diff] [blame] | 707 | tty_flip_buffer_push(&hp->port); |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 708 | } |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 709 | tty_kref_put(tty); |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 710 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | return poll_mask; |
| 712 | } |
Christian Borntraeger | 7721c49 | 2008-07-25 12:06:06 -0500 | [diff] [blame] | 713 | EXPORT_SYMBOL_GPL(hvc_poll); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 714 | |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 715 | /** |
Hendrik Brueckner | 254be49 | 2009-08-27 01:45:39 +0000 | [diff] [blame] | 716 | * __hvc_resize() - Update terminal window size information. |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 717 | * @hp: HVC console pointer |
| 718 | * @ws: Terminal window size structure |
| 719 | * |
| 720 | * Stores the specified window size information in the hvc structure of @hp. |
| 721 | * The function schedule the tty resize update. |
| 722 | * |
| 723 | * Locking: Locking free; the function MUST be called holding hp->lock |
| 724 | */ |
Hendrik Brueckner | 254be49 | 2009-08-27 01:45:39 +0000 | [diff] [blame] | 725 | void __hvc_resize(struct hvc_struct *hp, struct winsize ws) |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 726 | { |
Hendrik Brueckner | 7947cf0 | 2008-11-18 01:28:28 +0000 | [diff] [blame] | 727 | hp->ws = ws; |
| 728 | schedule_work(&hp->tty_resize); |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 729 | } |
Hendrik Brueckner | 254be49 | 2009-08-27 01:45:39 +0000 | [diff] [blame] | 730 | EXPORT_SYMBOL_GPL(__hvc_resize); |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 731 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | /* |
| 733 | * This kthread is either polling or interrupt driven. This is determined by |
| 734 | * calling hvc_poll() who determines whether a console adapter support |
| 735 | * interrupts. |
| 736 | */ |
Adrian Bunk | 5605d4d | 2007-07-09 11:37:38 -0700 | [diff] [blame] | 737 | static int khvcd(void *unused) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | { |
| 739 | int poll_mask; |
| 740 | struct hvc_struct *hp; |
| 741 | |
Rafael J. Wysocki | 8314418 | 2007-07-17 04:03:35 -0700 | [diff] [blame] | 742 | set_freezable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 743 | do { |
| 744 | poll_mask = 0; |
| 745 | hvc_kicked = 0; |
Andrew Morton | b64074e | 2006-09-16 12:15:38 -0700 | [diff] [blame] | 746 | try_to_freeze(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 747 | wmb(); |
Michael Ellerman | 1c8950f | 2008-05-08 14:27:17 +1000 | [diff] [blame] | 748 | if (!cpus_are_in_xmon()) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 749 | spin_lock(&hvc_structs_lock); |
| 750 | list_for_each_entry(hp, &hvc_structs, next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 751 | poll_mask |= hvc_poll(hp); |
| 752 | } |
| 753 | spin_unlock(&hvc_structs_lock); |
| 754 | } else |
| 755 | poll_mask |= HVC_POLL_READ; |
| 756 | if (hvc_kicked) |
| 757 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | set_current_state(TASK_INTERRUPTIBLE); |
| 759 | if (!hvc_kicked) { |
| 760 | if (poll_mask == 0) |
| 761 | schedule(); |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 762 | else { |
Benjamin Herrenschmidt | 15a2743 | 2014-05-23 19:41:06 +1000 | [diff] [blame] | 763 | unsigned long j_timeout; |
| 764 | |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 765 | if (timeout < MAX_TIMEOUT) |
| 766 | timeout += (timeout >> 6) + 1; |
| 767 | |
Benjamin Herrenschmidt | 15a2743 | 2014-05-23 19:41:06 +1000 | [diff] [blame] | 768 | /* |
| 769 | * We don't use msleep_interruptible otherwise |
| 770 | * "kick" will fail to wake us up |
| 771 | */ |
| 772 | j_timeout = msecs_to_jiffies(timeout) + 1; |
| 773 | schedule_timeout_interruptible(j_timeout); |
Will Schmidt | b791072 | 2007-04-18 00:44:46 +1000 | [diff] [blame] | 774 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | } |
| 776 | __set_current_state(TASK_RUNNING); |
| 777 | } while (!kthread_should_stop()); |
| 778 | |
| 779 | return 0; |
| 780 | } |
| 781 | |
Benjamin Herrenschmidt | 4d2bb3f | 2011-05-12 13:46:38 +1000 | [diff] [blame] | 782 | static int hvc_tiocmget(struct tty_struct *tty) |
| 783 | { |
| 784 | struct hvc_struct *hp = tty->driver_data; |
| 785 | |
| 786 | if (!hp || !hp->ops->tiocmget) |
| 787 | return -EINVAL; |
| 788 | return hp->ops->tiocmget(hp); |
| 789 | } |
| 790 | |
| 791 | static int hvc_tiocmset(struct tty_struct *tty, |
| 792 | unsigned int set, unsigned int clear) |
| 793 | { |
| 794 | struct hvc_struct *hp = tty->driver_data; |
| 795 | |
| 796 | if (!hp || !hp->ops->tiocmset) |
| 797 | return -EINVAL; |
| 798 | return hp->ops->tiocmset(hp, set, clear); |
| 799 | } |
| 800 | |
Anton Blanchard | 762e77a | 2011-07-12 19:44:05 +0000 | [diff] [blame] | 801 | #ifdef CONFIG_CONSOLE_POLL |
Rashika Kheria | 5855b21 | 2013-12-16 16:31:28 +0530 | [diff] [blame] | 802 | static int hvc_poll_init(struct tty_driver *driver, int line, char *options) |
Anton Blanchard | 762e77a | 2011-07-12 19:44:05 +0000 | [diff] [blame] | 803 | { |
| 804 | return 0; |
| 805 | } |
| 806 | |
| 807 | static int hvc_poll_get_char(struct tty_driver *driver, int line) |
| 808 | { |
| 809 | struct tty_struct *tty = driver->ttys[0]; |
| 810 | struct hvc_struct *hp = tty->driver_data; |
| 811 | int n; |
| 812 | char ch; |
| 813 | |
| 814 | n = hp->ops->get_chars(hp->vtermno, &ch, 1); |
| 815 | |
| 816 | if (n == 0) |
| 817 | return NO_POLL_CHAR; |
| 818 | |
| 819 | return ch; |
| 820 | } |
| 821 | |
| 822 | static void hvc_poll_put_char(struct tty_driver *driver, int line, char ch) |
| 823 | { |
| 824 | struct tty_struct *tty = driver->ttys[0]; |
| 825 | struct hvc_struct *hp = tty->driver_data; |
| 826 | int n; |
| 827 | |
| 828 | do { |
| 829 | n = hp->ops->put_chars(hp->vtermno, &ch, 1); |
| 830 | } while (n <= 0); |
| 831 | } |
| 832 | #endif |
| 833 | |
Jeff Dike | b68e31d | 2006-10-02 02:17:18 -0700 | [diff] [blame] | 834 | static const struct tty_operations hvc_ops = { |
Jiri Slaby | bdb498c | 2012-08-07 21:48:04 +0200 | [diff] [blame] | 835 | .install = hvc_install, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 836 | .open = hvc_open, |
| 837 | .close = hvc_close, |
Jiri Slaby | bdb498c | 2012-08-07 21:48:04 +0200 | [diff] [blame] | 838 | .cleanup = hvc_cleanup, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | .write = hvc_write, |
| 840 | .hangup = hvc_hangup, |
| 841 | .unthrottle = hvc_unthrottle, |
| 842 | .write_room = hvc_write_room, |
| 843 | .chars_in_buffer = hvc_chars_in_buffer, |
Benjamin Herrenschmidt | 4d2bb3f | 2011-05-12 13:46:38 +1000 | [diff] [blame] | 844 | .tiocmget = hvc_tiocmget, |
| 845 | .tiocmset = hvc_tiocmset, |
Anton Blanchard | 762e77a | 2011-07-12 19:44:05 +0000 | [diff] [blame] | 846 | #ifdef CONFIG_CONSOLE_POLL |
| 847 | .poll_init = hvc_poll_init, |
| 848 | .poll_get_char = hvc_poll_get_char, |
| 849 | .poll_put_char = hvc_poll_put_char, |
| 850 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | }; |
| 852 | |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 853 | static const struct tty_port_operations hvc_port_ops = { |
| 854 | .destruct = hvc_port_destruct, |
| 855 | }; |
| 856 | |
Amit Shah | 119ea10 | 2010-01-18 03:44:58 +0000 | [diff] [blame] | 857 | struct hvc_struct *hvc_alloc(uint32_t vtermno, int data, |
| 858 | const struct hv_ops *ops, |
| 859 | int outbuf_size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 860 | { |
| 861 | struct hvc_struct *hp; |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 862 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 863 | |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 864 | /* We wait until a driver actually comes along */ |
Paul Gortmaker | f76a1cb | 2014-01-14 16:03:37 -0500 | [diff] [blame] | 865 | if (atomic_inc_not_zero(&hvc_needs_init)) { |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 866 | int err = hvc_init(); |
| 867 | if (err) |
| 868 | return ERR_PTR(err); |
| 869 | } |
| 870 | |
Milton Miller | 2da7582 | 2009-01-08 02:14:28 +0000 | [diff] [blame] | 871 | hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size, |
Stephen Rothwell | 4e9e95a | 2006-07-13 18:53:32 +1000 | [diff] [blame] | 872 | GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | if (!hp) |
Milton Miller | acad955 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 874 | return ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 875 | |
Milton Miller | acad955 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 876 | hp->vtermno = vtermno; |
Christian Borntraeger | 611e097 | 2008-06-20 15:24:08 +0200 | [diff] [blame] | 877 | hp->data = data; |
Milton Miller | 030ffad | 2005-07-07 17:56:25 -0700 | [diff] [blame] | 878 | hp->ops = ops; |
Stephen Rothwell | 4e9e95a | 2006-07-13 18:53:32 +1000 | [diff] [blame] | 879 | hp->outbuf_size = outbuf_size; |
| 880 | hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 881 | |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 882 | tty_port_init(&hp->port); |
| 883 | hp->port.ops = &hvc_port_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 884 | |
Hendrik Brueckner | febde37 | 2008-10-14 05:02:09 +0000 | [diff] [blame] | 885 | INIT_WORK(&hp->tty_resize, hvc_set_winsz); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 886 | spin_lock_init(&hp->lock); |
| 887 | spin_lock(&hvc_structs_lock); |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 888 | |
| 889 | /* |
| 890 | * find index to use: |
| 891 | * see if this vterm id matches one registered for console. |
| 892 | */ |
Linus Torvalds | 3155521 | 2011-11-06 22:22:16 -0800 | [diff] [blame] | 893 | for (i=0; i < MAX_NR_HVC_CONSOLES; i++) |
Ryan S. Arnold | 45d607e | 2006-03-27 21:25:16 +0200 | [diff] [blame] | 894 | if (vtermnos[i] == hp->vtermno && |
| 895 | cons_ops[i] == hp->ops) |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 896 | break; |
| 897 | |
| 898 | /* no matching slot, just use a counter */ |
| 899 | if (i >= MAX_NR_HVC_CONSOLES) |
| 900 | i = ++last_hvc; |
| 901 | |
| 902 | hp->index = i; |
Benjamin Herrenschmidt | 92057a4 | 2012-07-23 21:33:13 +0000 | [diff] [blame] | 903 | cons_ops[i] = ops; |
| 904 | vtermnos[i] = vtermno; |
Milton Miller | 6f24808 | 2005-07-07 17:56:17 -0700 | [diff] [blame] | 905 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | list_add_tail(&(hp->next), &hvc_structs); |
| 907 | spin_unlock(&hvc_structs_lock); |
| 908 | |
Benjamin Herrenschmidt | 92057a4 | 2012-07-23 21:33:13 +0000 | [diff] [blame] | 909 | /* check if we need to re-register the kernel console */ |
| 910 | hvc_check_console(i); |
| 911 | |
Milton Miller | acad955 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 912 | return hp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | } |
Christian Borntraeger | 7721c49 | 2008-07-25 12:06:06 -0500 | [diff] [blame] | 914 | EXPORT_SYMBOL_GPL(hvc_alloc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | |
Hendrik Brueckner | 934752d | 2008-10-13 23:12:52 +0000 | [diff] [blame] | 916 | int hvc_remove(struct hvc_struct *hp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 917 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 919 | struct tty_struct *tty; |
| 920 | |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 921 | tty = tty_port_tty_get(&hp->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 922 | |
Jiri Slaby | 85bbc00 | 2012-04-02 13:54:22 +0200 | [diff] [blame] | 923 | spin_lock_irqsave(&hp->lock, flags); |
Benjamin Herrenschmidt | 92057a4 | 2012-07-23 21:33:13 +0000 | [diff] [blame] | 924 | if (hp->index < MAX_NR_HVC_CONSOLES) { |
| 925 | console_lock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 926 | vtermnos[hp->index] = -1; |
Benjamin Herrenschmidt | 92057a4 | 2012-07-23 21:33:13 +0000 | [diff] [blame] | 927 | cons_ops[hp->index] = NULL; |
| 928 | console_unlock(); |
| 929 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | |
| 931 | /* Don't whack hp->irq because tty_hangup() will need to free the irq. */ |
| 932 | |
| 933 | spin_unlock_irqrestore(&hp->lock, flags); |
| 934 | |
| 935 | /* |
Greg Kroah-Hartman | 12b20de | 2007-11-28 10:46:22 -0800 | [diff] [blame] | 936 | * We 'put' the instance that was grabbed when the kref instance |
| 937 | * was initialized using kref_init(). Let the last holder of this |
Amit Shah | e74d098 | 2010-03-12 11:53:15 +0530 | [diff] [blame] | 938 | * kref cause it to be removed, which will probably be the tty_vhangup |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 939 | * below. |
| 940 | */ |
Jiri Slaby | f3d9f25 | 2012-04-02 13:54:21 +0200 | [diff] [blame] | 941 | tty_port_put(&hp->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 942 | |
| 943 | /* |
Amit Shah | e74d098 | 2010-03-12 11:53:15 +0530 | [diff] [blame] | 944 | * This function call will auto chain call hvc_hangup. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 945 | */ |
Amit Shah | e74d098 | 2010-03-12 11:53:15 +0530 | [diff] [blame] | 946 | if (tty) { |
| 947 | tty_vhangup(tty); |
| 948 | tty_kref_put(tty); |
| 949 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 950 | return 0; |
| 951 | } |
Amit Shah | c0cefeb | 2009-11-27 20:50:49 +0000 | [diff] [blame] | 952 | EXPORT_SYMBOL_GPL(hvc_remove); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 953 | |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 954 | /* Driver initialization: called as soon as someone uses hvc_alloc(). */ |
| 955 | static int hvc_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 956 | { |
Michael Neuling | 55aab8c | 2006-03-25 17:30:00 +1100 | [diff] [blame] | 957 | struct tty_driver *drv; |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 958 | int err; |
Michael Neuling | 55aab8c | 2006-03-25 17:30:00 +1100 | [diff] [blame] | 959 | |
Milton Miller | 5f6d9c0 | 2005-07-07 17:56:21 -0700 | [diff] [blame] | 960 | /* We need more than hvc_count adapters due to hotplug additions. */ |
Michael Neuling | 55aab8c | 2006-03-25 17:30:00 +1100 | [diff] [blame] | 961 | drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS); |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 962 | if (!drv) { |
| 963 | err = -ENOMEM; |
| 964 | goto out; |
| 965 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | |
Michael Neuling | 55aab8c | 2006-03-25 17:30:00 +1100 | [diff] [blame] | 967 | drv->driver_name = "hvc"; |
| 968 | drv->name = "hvc"; |
| 969 | drv->major = HVC_MAJOR; |
| 970 | drv->minor_start = HVC_MINOR; |
| 971 | drv->type = TTY_DRIVER_TYPE_SYSTEM; |
| 972 | drv->init_termios = tty_std_termios; |
Hendrik Brueckner | 56ce9e2 | 2008-10-13 23:12:49 +0000 | [diff] [blame] | 973 | drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS; |
Michael Neuling | 55aab8c | 2006-03-25 17:30:00 +1100 | [diff] [blame] | 974 | tty_set_operations(drv, &hvc_ops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 975 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | /* Always start the kthread because there can be hotplug vty adapters |
| 977 | * added later. */ |
| 978 | hvc_task = kthread_run(khvcd, NULL, "khvcd"); |
| 979 | if (IS_ERR(hvc_task)) { |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 980 | printk(KERN_ERR "Couldn't create kthread for console.\n"); |
| 981 | err = PTR_ERR(hvc_task); |
| 982 | goto put_tty; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 983 | } |
| 984 | |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 985 | err = tty_register_driver(drv); |
| 986 | if (err) { |
| 987 | printk(KERN_ERR "Couldn't register hvc console driver\n"); |
| 988 | goto stop_thread; |
| 989 | } |
Anton Blanchard | ef4cbee | 2005-09-14 14:19:18 -0700 | [diff] [blame] | 990 | |
Milton Miller | 9fef3d2 | 2009-01-08 02:14:18 +0000 | [diff] [blame] | 991 | /* |
| 992 | * Make sure tty is fully registered before allowing it to be |
| 993 | * found by hvc_console_device. |
| 994 | */ |
| 995 | smp_mb(); |
Michael Neuling | 55aab8c | 2006-03-25 17:30:00 +1100 | [diff] [blame] | 996 | hvc_driver = drv; |
Milton Miller | acad955 | 2005-07-07 17:56:24 -0700 | [diff] [blame] | 997 | return 0; |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 998 | |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 999 | stop_thread: |
| 1000 | kthread_stop(hvc_task); |
| 1001 | hvc_task = NULL; |
Julia Lawall | 2571cd6a | 2008-10-13 10:31:49 +0100 | [diff] [blame] | 1002 | put_tty: |
| 1003 | put_tty_driver(drv); |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 1004 | out: |
| 1005 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1006 | } |
| 1007 | |
will schmidt | c3ea692 | 2007-04-18 00:54:51 +1000 | [diff] [blame] | 1008 | /* This isn't particularly necessary due to this being a console driver |
Milton Miller | 320da0d | 2005-07-07 17:56:20 -0700 | [diff] [blame] | 1009 | * but it is nice to be thorough. |
| 1010 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1011 | static void __exit hvc_exit(void) |
| 1012 | { |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 1013 | if (hvc_driver) { |
| 1014 | kthread_stop(hvc_task); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1015 | |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 1016 | tty_unregister_driver(hvc_driver); |
| 1017 | /* return tty_struct instances allocated in hvc_init(). */ |
| 1018 | put_tty_driver(hvc_driver); |
Chris Metcalf | 4455b11 | 2010-07-06 08:03:16 +0000 | [diff] [blame] | 1019 | unregister_console(&hvc_console); |
Rusty Russell | 3e6c6f6 | 2007-10-16 23:30:13 -0700 | [diff] [blame] | 1020 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1022 | module_exit(hvc_exit); |