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authorGreg Kroah-Hartman <gregkh@suse.de>2011-01-13 15:03:00 -0500
committerGreg Kroah-Hartman <gregkh@suse.de>2011-01-13 15:03:00 -0500
commit728674a7e466628df2aeec6d11a2ae1ef968fb67 (patch)
tree83d2e44d05b257ab03230f5c95e0d6843f0ed2f9 /drivers/tty/hvc
parente691d24e9c5007486bef59c589c2a2d784e0c30b (diff)
tty: move hvc drivers to drivers/tty/hvc/
As requested by Arnd Bergmann, the hvc drivers are now moved to the drivers/tty/hvc/ directory. The virtio_console.c driver was also moved, as it required the hvc_console.h file to be able to be built, and it really is a hvc driver. Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty/hvc')
-rw-r--r--drivers/tty/hvc/Makefile13
-rw-r--r--drivers/tty/hvc/hvc_beat.c134
-rw-r--r--drivers/tty/hvc/hvc_console.c914
-rw-r--r--drivers/tty/hvc/hvc_console.h119
-rw-r--r--drivers/tty/hvc/hvc_dcc.c133
-rw-r--r--drivers/tty/hvc/hvc_irq.c49
-rw-r--r--drivers/tty/hvc/hvc_iseries.c598
-rw-r--r--drivers/tty/hvc/hvc_iucv.c1337
-rw-r--r--drivers/tty/hvc/hvc_rtas.c133
-rw-r--r--drivers/tty/hvc/hvc_tile.c68
-rw-r--r--drivers/tty/hvc/hvc_udbg.c96
-rw-r--r--drivers/tty/hvc/hvc_vio.c173
-rw-r--r--drivers/tty/hvc/hvc_xen.c271
-rw-r--r--drivers/tty/hvc/hvcs.c1604
-rw-r--r--drivers/tty/hvc/hvsi.c1314
-rw-r--r--drivers/tty/hvc/virtio_console.c1838
16 files changed, 8794 insertions, 0 deletions
diff --git a/drivers/tty/hvc/Makefile b/drivers/tty/hvc/Makefile
new file mode 100644
index 000000000000..e6bed5f177ff
--- /dev/null
+++ b/drivers/tty/hvc/Makefile
@@ -0,0 +1,13 @@
1obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o
2obj-$(CONFIG_HVC_ISERIES) += hvc_iseries.o
3obj-$(CONFIG_HVC_RTAS) += hvc_rtas.o
4obj-$(CONFIG_HVC_TILE) += hvc_tile.o
5obj-$(CONFIG_HVC_DCC) += hvc_dcc.o
6obj-$(CONFIG_HVC_BEAT) += hvc_beat.o
7obj-$(CONFIG_HVC_DRIVER) += hvc_console.o
8obj-$(CONFIG_HVC_IRQ) += hvc_irq.o
9obj-$(CONFIG_HVC_XEN) += hvc_xen.o
10obj-$(CONFIG_HVC_IUCV) += hvc_iucv.o
11obj-$(CONFIG_HVC_UDBG) += hvc_udbg.o
12obj-$(CONFIG_HVCS) += hvcs.o
13obj-$(CONFIG_VIRTIO_CONSOLE) += virtio_console.o
diff --git a/drivers/tty/hvc/hvc_beat.c b/drivers/tty/hvc/hvc_beat.c
new file mode 100644
index 000000000000..5fe4631e2a61
--- /dev/null
+++ b/drivers/tty/hvc/hvc_beat.c
@@ -0,0 +1,134 @@
1/*
2 * Beat hypervisor console driver
3 *
4 * (C) Copyright 2006 TOSHIBA CORPORATION
5 *
6 * This code is based on drivers/char/hvc_rtas.c:
7 * (C) Copyright IBM Corporation 2001-2005
8 * (C) Copyright Red Hat, Inc. 2005
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 along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23 */
24
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/err.h>
28#include <linux/string.h>
29#include <linux/console.h>
30#include <asm/prom.h>
31#include <asm/hvconsole.h>
32#include <asm/firmware.h>
33
34#include "hvc_console.h"
35
36extern int64_t beat_get_term_char(uint64_t, uint64_t *, uint64_t *, uint64_t *);
37extern int64_t beat_put_term_char(uint64_t, uint64_t, uint64_t, uint64_t);
38
39struct hvc_struct *hvc_beat_dev = NULL;
40
41/* bug: only one queue is available regardless of vtermno */
42static int hvc_beat_get_chars(uint32_t vtermno, char *buf, int cnt)
43{
44 static unsigned char q[sizeof(unsigned long) * 2]
45 __attribute__((aligned(sizeof(unsigned long))));
46 static int qlen = 0;
47 u64 got;
48
49again:
50 if (qlen) {
51 if (qlen > cnt) {
52 memcpy(buf, q, cnt);
53 qlen -= cnt;
54 memmove(q + cnt, q, qlen);
55 return cnt;
56 } else { /* qlen <= cnt */
57 int r;
58
59 memcpy(buf, q, qlen);
60 r = qlen;
61 qlen = 0;
62 return r;
63 }
64 }
65 if (beat_get_term_char(vtermno, &got,
66 ((u64 *)q), ((u64 *)q) + 1) == 0) {
67 qlen = got;
68 goto again;
69 }
70 return 0;
71}
72
73static int hvc_beat_put_chars(uint32_t vtermno, const char *buf, int cnt)
74{
75 unsigned long kb[2];
76 int rest, nlen;
77
78 for (rest = cnt; rest > 0; rest -= nlen) {
79 nlen = (rest > 16) ? 16 : rest;
80 memcpy(kb, buf, nlen);
81 beat_put_term_char(vtermno, nlen, kb[0], kb[1]);
82 buf += nlen;
83 }
84 return cnt;
85}
86
87static const struct hv_ops hvc_beat_get_put_ops = {
88 .get_chars = hvc_beat_get_chars,
89 .put_chars = hvc_beat_put_chars,
90};
91
92static int hvc_beat_useit = 1;
93
94static int hvc_beat_config(char *p)
95{
96 hvc_beat_useit = simple_strtoul(p, NULL, 0);
97 return 0;
98}
99
100static int __init hvc_beat_console_init(void)
101{
102 if (hvc_beat_useit && of_machine_is_compatible("Beat")) {
103 hvc_instantiate(0, 0, &hvc_beat_get_put_ops);
104 }
105 return 0;
106}
107
108/* temp */
109static int __init hvc_beat_init(void)
110{
111 struct hvc_struct *hp;
112
113 if (!firmware_has_feature(FW_FEATURE_BEAT))
114 return -ENODEV;
115
116 hp = hvc_alloc(0, NO_IRQ, &hvc_beat_get_put_ops, 16);
117 if (IS_ERR(hp))
118 return PTR_ERR(hp);
119 hvc_beat_dev = hp;
120 return 0;
121}
122
123static void __exit hvc_beat_exit(void)
124{
125 if (hvc_beat_dev)
126 hvc_remove(hvc_beat_dev);
127}
128
129module_init(hvc_beat_init);
130module_exit(hvc_beat_exit);
131
132__setup("hvc_beat=", hvc_beat_config);
133
134console_initcall(hvc_beat_console_init);
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
new file mode 100644
index 000000000000..e9cba13ee800
--- /dev/null
+++ b/drivers/tty/hvc/hvc_console.c
@@ -0,0 +1,914 @@
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>
30#include <linux/kthread.h>
31#include <linux/list.h>
32#include <linux/module.h>
33#include <linux/major.h>
34#include <linux/sysrq.h>
35#include <linux/tty.h>
36#include <linux/tty_flip.h>
37#include <linux/sched.h>
38#include <linux/spinlock.h>
39#include <linux/delay.h>
40#include <linux/freezer.h>
41#include <linux/slab.h>
42
43#include <asm/uaccess.h>
44
45#include "hvc_console.h"
46
47#define HVC_MAJOR 229
48#define HVC_MINOR 0
49
50/*
51 * Wait this long per iteration while trying to push buffered data to the
52 * hypervisor before allowing the tty to complete a close operation.
53 */
54#define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
55
56/*
57 * These sizes are most efficient for vio, because they are the
58 * native transfer size. We could make them selectable in the
59 * future to better deal with backends that want other buffer sizes.
60 */
61#define N_OUTBUF 16
62#define N_INBUF 16
63
64#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
65
66static struct tty_driver *hvc_driver;
67static struct task_struct *hvc_task;
68
69/* Picks up late kicks after list walk but before schedule() */
70static int hvc_kicked;
71
72static int hvc_init(void);
73
74#ifdef CONFIG_MAGIC_SYSRQ
75static int sysrq_pressed;
76#endif
77
78/* dynamic list of hvc_struct instances */
79static LIST_HEAD(hvc_structs);
80
81/*
82 * Protect the list of hvc_struct instances from inserts and removals during
83 * list traversal.
84 */
85static DEFINE_SPINLOCK(hvc_structs_lock);
86
87/*
88 * This value is used to assign a tty->index value to a hvc_struct based
89 * upon order of exposure via hvc_probe(), when we can not match it to
90 * a console candidate registered with hvc_instantiate().
91 */
92static int last_hvc = -1;
93
94/*
95 * Do not call this function with either the hvc_structs_lock or the hvc_struct
96 * lock held. If successful, this function increments the kref reference
97 * count against the target hvc_struct so it should be released when finished.
98 */
99static struct hvc_struct *hvc_get_by_index(int index)
100{
101 struct hvc_struct *hp;
102 unsigned long flags;
103
104 spin_lock(&hvc_structs_lock);
105
106 list_for_each_entry(hp, &hvc_structs, next) {
107 spin_lock_irqsave(&hp->lock, flags);
108 if (hp->index == index) {
109 kref_get(&hp->kref);
110 spin_unlock_irqrestore(&hp->lock, flags);
111 spin_unlock(&hvc_structs_lock);
112 return hp;
113 }
114 spin_unlock_irqrestore(&hp->lock, flags);
115 }
116 hp = NULL;
117
118 spin_unlock(&hvc_structs_lock);
119 return hp;
120}
121
122
123/*
124 * Initial console vtermnos for console API usage prior to full console
125 * initialization. Any vty adapter outside this range will not have usable
126 * console interfaces but can still be used as a tty device. This has to be
127 * static because kmalloc will not work during early console init.
128 */
129static const struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES];
130static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] =
131 {[0 ... MAX_NR_HVC_CONSOLES - 1] = -1};
132
133/*
134 * Console APIs, NOT TTY. These APIs are available immediately when
135 * hvc_console_setup() finds adapters.
136 */
137
138static void hvc_console_print(struct console *co, const char *b,
139 unsigned count)
140{
141 char c[N_OUTBUF] __ALIGNED__;
142 unsigned i = 0, n = 0;
143 int r, donecr = 0, index = co->index;
144
145 /* Console access attempt outside of acceptable console range. */
146 if (index >= MAX_NR_HVC_CONSOLES)
147 return;
148
149 /* This console adapter was removed so it is not usable. */
150 if (vtermnos[index] == -1)
151 return;
152
153 while (count > 0 || i > 0) {
154 if (count > 0 && i < sizeof(c)) {
155 if (b[n] == '\n' && !donecr) {
156 c[i++] = '\r';
157 donecr = 1;
158 } else {
159 c[i++] = b[n++];
160 donecr = 0;
161 --count;
162 }
163 } else {
164 r = cons_ops[index]->put_chars(vtermnos[index], c, i);
165 if (r <= 0) {
166 /* throw away chars on error */
167 i = 0;
168 } else if (r > 0) {
169 i -= r;
170 if (i > 0)
171 memmove(c, c+r, i);
172 }
173 }
174 }
175}
176
177static struct tty_driver *hvc_console_device(struct console *c, int *index)
178{
179 if (vtermnos[c->index] == -1)
180 return NULL;
181
182 *index = c->index;
183 return hvc_driver;
184}
185
186static int __init hvc_console_setup(struct console *co, char *options)
187{
188 if (co->index < 0 || co->index >= MAX_NR_HVC_CONSOLES)
189 return -ENODEV;
190
191 if (vtermnos[co->index] == -1)
192 return -ENODEV;
193
194 return 0;
195}
196
197static struct console hvc_console = {
198 .name = "hvc",
199 .write = hvc_console_print,
200 .device = hvc_console_device,
201 .setup = hvc_console_setup,
202 .flags = CON_PRINTBUFFER,
203 .index = -1,
204};
205
206/*
207 * Early console initialization. Precedes driver initialization.
208 *
209 * (1) we are first, and the user specified another driver
210 * -- index will remain -1
211 * (2) we are first and the user specified no driver
212 * -- index will be set to 0, then we will fail setup.
213 * (3) we are first and the user specified our driver
214 * -- index will be set to user specified driver, and we will fail
215 * (4) we are after driver, and this initcall will register us
216 * -- if the user didn't specify a driver then the console will match
217 *
218 * Note that for cases 2 and 3, we will match later when the io driver
219 * calls hvc_instantiate() and call register again.
220 */
221static int __init hvc_console_init(void)
222{
223 register_console(&hvc_console);
224 return 0;
225}
226console_initcall(hvc_console_init);
227
228/* callback when the kboject ref count reaches zero. */
229static void destroy_hvc_struct(struct kref *kref)
230{
231 struct hvc_struct *hp = container_of(kref, struct hvc_struct, kref);
232 unsigned long flags;
233
234 spin_lock(&hvc_structs_lock);
235
236 spin_lock_irqsave(&hp->lock, flags);
237 list_del(&(hp->next));
238 spin_unlock_irqrestore(&hp->lock, flags);
239
240 spin_unlock(&hvc_structs_lock);
241
242 kfree(hp);
243}
244
245/*
246 * hvc_instantiate() is an early console discovery method which locates
247 * consoles * prior to the vio subsystem discovering them. Hotplugged
248 * vty adapters do NOT get an hvc_instantiate() callback since they
249 * appear after early console init.
250 */
251int hvc_instantiate(uint32_t vtermno, int index, const struct hv_ops *ops)
252{
253 struct hvc_struct *hp;
254
255 if (index < 0 || index >= MAX_NR_HVC_CONSOLES)
256 return -1;
257
258 if (vtermnos[index] != -1)
259 return -1;
260
261 /* make sure no no tty has been registered in this index */
262 hp = hvc_get_by_index(index);
263 if (hp) {
264 kref_put(&hp->kref, destroy_hvc_struct);
265 return -1;
266 }
267
268 vtermnos[index] = vtermno;
269 cons_ops[index] = ops;
270
271 /* reserve all indices up to and including this index */
272 if (last_hvc < index)
273 last_hvc = index;
274
275 /* if this index is what the user requested, then register
276 * now (setup won't fail at this point). It's ok to just
277 * call register again if previously .setup failed.
278 */
279 if (index == hvc_console.index)
280 register_console(&hvc_console);
281
282 return 0;
283}
284EXPORT_SYMBOL_GPL(hvc_instantiate);
285
286/* Wake the sleeping khvcd */
287void hvc_kick(void)
288{
289 hvc_kicked = 1;
290 wake_up_process(hvc_task);
291}
292EXPORT_SYMBOL_GPL(hvc_kick);
293
294static void hvc_unthrottle(struct tty_struct *tty)
295{
296 hvc_kick();
297}
298
299/*
300 * The TTY interface won't be used until after the vio layer has exposed the vty
301 * adapter to the kernel.
302 */
303static int hvc_open(struct tty_struct *tty, struct file * filp)
304{
305 struct hvc_struct *hp;
306 unsigned long flags;
307 int rc = 0;
308
309 /* Auto increments kref reference if found. */
310 if (!(hp = hvc_get_by_index(tty->index)))
311 return -ENODEV;
312
313 spin_lock_irqsave(&hp->lock, flags);
314 /* Check and then increment for fast path open. */
315 if (hp->count++ > 0) {
316 tty_kref_get(tty);
317 spin_unlock_irqrestore(&hp->lock, flags);
318 hvc_kick();
319 return 0;
320 } /* else count == 0 */
321
322 tty->driver_data = hp;
323
324 hp->tty = tty_kref_get(tty);
325
326 spin_unlock_irqrestore(&hp->lock, flags);
327
328 if (hp->ops->notifier_add)
329 rc = hp->ops->notifier_add(hp, hp->data);
330
331 /*
332 * If the notifier fails we return an error. The tty layer
333 * will call hvc_close() after a failed open but we don't want to clean
334 * up there so we'll clean up here and clear out the previously set
335 * tty fields and return the kref reference.
336 */
337 if (rc) {
338 spin_lock_irqsave(&hp->lock, flags);
339 hp->tty = NULL;
340 spin_unlock_irqrestore(&hp->lock, flags);
341 tty_kref_put(tty);
342 tty->driver_data = NULL;
343 kref_put(&hp->kref, destroy_hvc_struct);
344 printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
345 }
346 /* Force wakeup of the polling thread */
347 hvc_kick();
348
349 return rc;
350}
351
352static void hvc_close(struct tty_struct *tty, struct file * filp)
353{
354 struct hvc_struct *hp;
355 unsigned long flags;
356
357 if (tty_hung_up_p(filp))
358 return;
359
360 /*
361 * No driver_data means that this close was issued after a failed
362 * hvc_open by the tty layer's release_dev() function and we can just
363 * exit cleanly because the kref reference wasn't made.
364 */
365 if (!tty->driver_data)
366 return;
367
368 hp = tty->driver_data;
369
370 spin_lock_irqsave(&hp->lock, flags);
371
372 if (--hp->count == 0) {
373 /* We are done with the tty pointer now. */
374 hp->tty = NULL;
375 spin_unlock_irqrestore(&hp->lock, flags);
376
377 if (hp->ops->notifier_del)
378 hp->ops->notifier_del(hp, hp->data);
379
380 /* cancel pending tty resize work */
381 cancel_work_sync(&hp->tty_resize);
382
383 /*
384 * Chain calls chars_in_buffer() and returns immediately if
385 * there is no buffered data otherwise sleeps on a wait queue
386 * waking periodically to check chars_in_buffer().
387 */
388 tty_wait_until_sent(tty, HVC_CLOSE_WAIT);
389 } else {
390 if (hp->count < 0)
391 printk(KERN_ERR "hvc_close %X: oops, count is %d\n",
392 hp->vtermno, hp->count);
393 spin_unlock_irqrestore(&hp->lock, flags);
394 }
395
396 tty_kref_put(tty);
397 kref_put(&hp->kref, destroy_hvc_struct);
398}
399
400static void hvc_hangup(struct tty_struct *tty)
401{
402 struct hvc_struct *hp = tty->driver_data;
403 unsigned long flags;
404 int temp_open_count;
405
406 if (!hp)
407 return;
408
409 /* cancel pending tty resize work */
410 cancel_work_sync(&hp->tty_resize);
411
412 spin_lock_irqsave(&hp->lock, flags);
413
414 /*
415 * The N_TTY line discipline has problems such that in a close vs
416 * open->hangup case this can be called after the final close so prevent
417 * that from happening for now.
418 */
419 if (hp->count <= 0) {
420 spin_unlock_irqrestore(&hp->lock, flags);
421 return;
422 }
423
424 temp_open_count = hp->count;
425 hp->count = 0;
426 hp->n_outbuf = 0;
427 hp->tty = NULL;
428
429 spin_unlock_irqrestore(&hp->lock, flags);
430
431 if (hp->ops->notifier_hangup)
432 hp->ops->notifier_hangup(hp, hp->data);
433
434 while(temp_open_count) {
435 --temp_open_count;
436 tty_kref_put(tty);
437 kref_put(&hp->kref, destroy_hvc_struct);
438 }
439}
440
441/*
442 * Push buffered characters whether they were just recently buffered or waiting
443 * on a blocked hypervisor. Call this function with hp->lock held.
444 */
445static int hvc_push(struct hvc_struct *hp)
446{
447 int n;
448
449 n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf);
450 if (n <= 0) {
451 if (n == 0) {
452 hp->do_wakeup = 1;
453 return 0;
454 }
455 /* throw away output on error; this happens when
456 there is no session connected to the vterm. */
457 hp->n_outbuf = 0;
458 } else
459 hp->n_outbuf -= n;
460 if (hp->n_outbuf > 0)
461 memmove(hp->outbuf, hp->outbuf + n, hp->n_outbuf);
462 else
463 hp->do_wakeup = 1;
464
465 return n;
466}
467
468static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
469{
470 struct hvc_struct *hp = tty->driver_data;
471 unsigned long flags;
472 int rsize, written = 0;
473
474 /* This write was probably executed during a tty close. */
475 if (!hp)
476 return -EPIPE;
477
478 if (hp->count <= 0)
479 return -EIO;
480
481 spin_lock_irqsave(&hp->lock, flags);
482
483 /* Push pending writes */
484 if (hp->n_outbuf > 0)
485 hvc_push(hp);
486
487 while (count > 0 && (rsize = hp->outbuf_size - hp->n_outbuf) > 0) {
488 if (rsize > count)
489 rsize = count;
490 memcpy(hp->outbuf + hp->n_outbuf, buf, rsize);
491 count -= rsize;
492 buf += rsize;
493 hp->n_outbuf += rsize;
494 written += rsize;
495 hvc_push(hp);
496 }
497 spin_unlock_irqrestore(&hp->lock, flags);
498
499 /*
500 * Racy, but harmless, kick thread if there is still pending data.
501 */
502 if (hp->n_outbuf)
503 hvc_kick();
504
505 return written;
506}
507
508/**
509 * hvc_set_winsz() - Resize the hvc tty terminal window.
510 * @work: work structure.
511 *
512 * The routine shall not be called within an atomic context because it
513 * might sleep.
514 *
515 * Locking: hp->lock
516 */
517static void hvc_set_winsz(struct work_struct *work)
518{
519 struct hvc_struct *hp;
520 unsigned long hvc_flags;
521 struct tty_struct *tty;
522 struct winsize ws;
523
524 hp = container_of(work, struct hvc_struct, tty_resize);
525
526 spin_lock_irqsave(&hp->lock, hvc_flags);
527 if (!hp->tty) {
528 spin_unlock_irqrestore(&hp->lock, hvc_flags);
529 return;
530 }
531 ws = hp->ws;
532 tty = tty_kref_get(hp->tty);
533 spin_unlock_irqrestore(&hp->lock, hvc_flags);
534
535 tty_do_resize(tty, &ws);
536 tty_kref_put(tty);
537}
538
539/*
540 * This is actually a contract between the driver and the tty layer outlining
541 * how much write room the driver can guarantee will be sent OR BUFFERED. This
542 * driver MUST honor the return value.
543 */
544static int hvc_write_room(struct tty_struct *tty)
545{
546 struct hvc_struct *hp = tty->driver_data;
547
548 if (!hp)
549 return -1;
550
551 return hp->outbuf_size - hp->n_outbuf;
552}
553
554static int hvc_chars_in_buffer(struct tty_struct *tty)
555{
556 struct hvc_struct *hp = tty->driver_data;
557
558 if (!hp)
559 return 0;
560 return hp->n_outbuf;
561}
562
563/*
564 * timeout will vary between the MIN and MAX values defined here. By default
565 * and during console activity we will use a default MIN_TIMEOUT of 10. When
566 * the console is idle, we increase the timeout value on each pass through
567 * msleep until we reach the max. This may be noticeable as a brief (average
568 * one second) delay on the console before the console responds to input when
569 * there has been no input for some time.
570 */
571#define MIN_TIMEOUT (10)
572#define MAX_TIMEOUT (2000)
573static u32 timeout = MIN_TIMEOUT;
574
575#define HVC_POLL_READ 0x00000001
576#define HVC_POLL_WRITE 0x00000002
577
578int hvc_poll(struct hvc_struct *hp)
579{
580 struct tty_struct *tty;
581 int i, n, poll_mask = 0;
582 char buf[N_INBUF] __ALIGNED__;
583 unsigned long flags;
584 int read_total = 0;
585 int written_total = 0;
586
587 spin_lock_irqsave(&hp->lock, flags);
588
589 /* Push pending writes */
590 if (hp->n_outbuf > 0)
591 written_total = hvc_push(hp);
592
593 /* Reschedule us if still some write pending */
594 if (hp->n_outbuf > 0) {
595 poll_mask |= HVC_POLL_WRITE;
596 /* If hvc_push() was not able to write, sleep a few msecs */
597 timeout = (written_total) ? 0 : MIN_TIMEOUT;
598 }
599
600 /* No tty attached, just skip */
601 tty = tty_kref_get(hp->tty);
602 if (tty == NULL)
603 goto bail;
604
605 /* Now check if we can get data (are we throttled ?) */
606 if (test_bit(TTY_THROTTLED, &tty->flags))
607 goto throttled;
608
609 /* If we aren't notifier driven and aren't throttled, we always
610 * request a reschedule
611 */
612 if (!hp->irq_requested)
613 poll_mask |= HVC_POLL_READ;
614
615 /* Read data if any */
616 for (;;) {
617 int count = tty_buffer_request_room(tty, N_INBUF);
618
619 /* If flip is full, just reschedule a later read */
620 if (count == 0) {
621 poll_mask |= HVC_POLL_READ;
622 break;
623 }
624
625 n = hp->ops->get_chars(hp->vtermno, buf, count);
626 if (n <= 0) {
627 /* Hangup the tty when disconnected from host */
628 if (n == -EPIPE) {
629 spin_unlock_irqrestore(&hp->lock, flags);
630 tty_hangup(tty);
631 spin_lock_irqsave(&hp->lock, flags);
632 } else if ( n == -EAGAIN ) {
633 /*
634 * Some back-ends can only ensure a certain min
635 * num of bytes read, which may be > 'count'.
636 * Let the tty clear the flip buff to make room.
637 */
638 poll_mask |= HVC_POLL_READ;
639 }
640 break;
641 }
642 for (i = 0; i < n; ++i) {
643#ifdef CONFIG_MAGIC_SYSRQ
644 if (hp->index == hvc_console.index) {
645 /* Handle the SysRq Hack */
646 /* XXX should support a sequence */
647 if (buf[i] == '\x0f') { /* ^O */
648 /* if ^O is pressed again, reset
649 * sysrq_pressed and flip ^O char */
650 sysrq_pressed = !sysrq_pressed;
651 if (sysrq_pressed)
652 continue;
653 } else if (sysrq_pressed) {
654 handle_sysrq(buf[i]);
655 sysrq_pressed = 0;
656 continue;
657 }
658 }
659#endif /* CONFIG_MAGIC_SYSRQ */
660 tty_insert_flip_char(tty, buf[i], 0);
661 }
662
663 read_total += n;
664 }
665 throttled:
666 /* Wakeup write queue if necessary */
667 if (hp->do_wakeup) {
668 hp->do_wakeup = 0;
669 tty_wakeup(tty);
670 }
671 bail:
672 spin_unlock_irqrestore(&hp->lock, flags);
673
674 if (read_total) {
675 /* Activity is occurring, so reset the polling backoff value to
676 a minimum for performance. */
677 timeout = MIN_TIMEOUT;
678
679 tty_flip_buffer_push(tty);
680 }
681 if (tty)
682 tty_kref_put(tty);
683
684 return poll_mask;
685}
686EXPORT_SYMBOL_GPL(hvc_poll);
687
688/**
689 * __hvc_resize() - Update terminal window size information.
690 * @hp: HVC console pointer
691 * @ws: Terminal window size structure
692 *
693 * Stores the specified window size information in the hvc structure of @hp.
694 * The function schedule the tty resize update.
695 *
696 * Locking: Locking free; the function MUST be called holding hp->lock
697 */
698void __hvc_resize(struct hvc_struct *hp, struct winsize ws)
699{
700 hp->ws = ws;
701 schedule_work(&hp->tty_resize);
702}
703EXPORT_SYMBOL_GPL(__hvc_resize);
704
705/*
706 * This kthread is either polling or interrupt driven. This is determined by
707 * calling hvc_poll() who determines whether a console adapter support
708 * interrupts.
709 */
710static int khvcd(void *unused)
711{
712 int poll_mask;
713 struct hvc_struct *hp;
714
715 set_freezable();
716 do {
717 poll_mask = 0;
718 hvc_kicked = 0;
719 try_to_freeze();
720 wmb();
721 if (!cpus_are_in_xmon()) {
722 spin_lock(&hvc_structs_lock);
723 list_for_each_entry(hp, &hvc_structs, next) {
724 poll_mask |= hvc_poll(hp);
725 }
726 spin_unlock(&hvc_structs_lock);
727 } else
728 poll_mask |= HVC_POLL_READ;
729 if (hvc_kicked)
730 continue;
731 set_current_state(TASK_INTERRUPTIBLE);
732 if (!hvc_kicked) {
733 if (poll_mask == 0)
734 schedule();
735 else {
736 if (timeout < MAX_TIMEOUT)
737 timeout += (timeout >> 6) + 1;
738
739 msleep_interruptible(timeout);
740 }
741 }
742 __set_current_state(TASK_RUNNING);
743 } while (!kthread_should_stop());
744
745 return 0;
746}
747
748static const struct tty_operations hvc_ops = {
749 .open = hvc_open,
750 .close = hvc_close,
751 .write = hvc_write,
752 .hangup = hvc_hangup,
753 .unthrottle = hvc_unthrottle,
754 .write_room = hvc_write_room,
755 .chars_in_buffer = hvc_chars_in_buffer,
756};
757
758struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
759 const struct hv_ops *ops,
760 int outbuf_size)
761{
762 struct hvc_struct *hp;
763 int i;
764
765 /* We wait until a driver actually comes along */
766 if (!hvc_driver) {
767 int err = hvc_init();
768 if (err)
769 return ERR_PTR(err);
770 }
771
772 hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
773 GFP_KERNEL);
774 if (!hp)
775 return ERR_PTR(-ENOMEM);
776
777 hp->vtermno = vtermno;
778 hp->data = data;
779 hp->ops = ops;
780 hp->outbuf_size = outbuf_size;
781 hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];
782
783 kref_init(&hp->kref);
784
785 INIT_WORK(&hp->tty_resize, hvc_set_winsz);
786 spin_lock_init(&hp->lock);
787 spin_lock(&hvc_structs_lock);
788
789 /*
790 * find index to use:
791 * see if this vterm id matches one registered for console.
792 */
793 for (i=0; i < MAX_NR_HVC_CONSOLES; i++)
794 if (vtermnos[i] == hp->vtermno &&
795 cons_ops[i] == hp->ops)
796 break;
797
798 /* no matching slot, just use a counter */
799 if (i >= MAX_NR_HVC_CONSOLES)
800 i = ++last_hvc;
801
802 hp->index = i;
803
804 list_add_tail(&(hp->next), &hvc_structs);
805 spin_unlock(&hvc_structs_lock);
806
807 return hp;
808}
809EXPORT_SYMBOL_GPL(hvc_alloc);
810
811int hvc_remove(struct hvc_struct *hp)
812{
813 unsigned long flags;
814 struct tty_struct *tty;
815
816 spin_lock_irqsave(&hp->lock, flags);
817 tty = tty_kref_get(hp->tty);
818
819 if (hp->index < MAX_NR_HVC_CONSOLES)
820 vtermnos[hp->index] = -1;
821
822 /* Don't whack hp->irq because tty_hangup() will need to free the irq. */
823
824 spin_unlock_irqrestore(&hp->lock, flags);
825
826 /*
827 * We 'put' the instance that was grabbed when the kref instance
828 * was initialized using kref_init(). Let the last holder of this
829 * kref cause it to be removed, which will probably be the tty_vhangup
830 * below.
831 */
832 kref_put(&hp->kref, destroy_hvc_struct);
833
834 /*
835 * This function call will auto chain call hvc_hangup.
836 */
837 if (tty) {
838 tty_vhangup(tty);
839 tty_kref_put(tty);
840 }
841 return 0;
842}
843EXPORT_SYMBOL_GPL(hvc_remove);
844
845/* Driver initialization: called as soon as someone uses hvc_alloc(). */
846static int hvc_init(void)
847{
848 struct tty_driver *drv;
849 int err;
850
851 /* We need more than hvc_count adapters due to hotplug additions. */
852 drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS);
853 if (!drv) {
854 err = -ENOMEM;
855 goto out;
856 }
857
858 drv->owner = THIS_MODULE;
859 drv->driver_name = "hvc";
860 drv->name = "hvc";
861 drv->major = HVC_MAJOR;
862 drv->minor_start = HVC_MINOR;
863 drv->type = TTY_DRIVER_TYPE_SYSTEM;
864 drv->init_termios = tty_std_termios;
865 drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
866 tty_set_operations(drv, &hvc_ops);
867
868 /* Always start the kthread because there can be hotplug vty adapters
869 * added later. */
870 hvc_task = kthread_run(khvcd, NULL, "khvcd");
871 if (IS_ERR(hvc_task)) {
872 printk(KERN_ERR "Couldn't create kthread for console.\n");
873 err = PTR_ERR(hvc_task);
874 goto put_tty;
875 }
876
877 err = tty_register_driver(drv);
878 if (err) {
879 printk(KERN_ERR "Couldn't register hvc console driver\n");
880 goto stop_thread;
881 }
882
883 /*
884 * Make sure tty is fully registered before allowing it to be
885 * found by hvc_console_device.
886 */
887 smp_mb();
888 hvc_driver = drv;
889 return 0;
890
891stop_thread:
892 kthread_stop(hvc_task);
893 hvc_task = NULL;
894put_tty:
895 put_tty_driver(drv);
896out:
897 return err;
898}
899
900/* This isn't particularly necessary due to this being a console driver
901 * but it is nice to be thorough.
902 */
903static void __exit hvc_exit(void)
904{
905 if (hvc_driver) {
906 kthread_stop(hvc_task);
907
908 tty_unregister_driver(hvc_driver);
909 /* return tty_struct instances allocated in hvc_init(). */
910 put_tty_driver(hvc_driver);
911 unregister_console(&hvc_console);
912 }
913}
914module_exit(hvc_exit);
diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h
new file mode 100644
index 000000000000..54381eba4e4a
--- /dev/null
+++ b/drivers/tty/hvc/hvc_console.h
@@ -0,0 +1,119 @@
1/*
2 * hvc_console.h
3 * Copyright (C) 2005 IBM Corporation
4 *
5 * Author(s):
6 * Ryan S. Arnold <rsa@us.ibm.com>
7 *
8 * hvc_console header information:
9 * moved here from arch/powerpc/include/asm/hvconsole.h
10 * and drivers/char/hvc_console.c
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 */
26
27#ifndef HVC_CONSOLE_H
28#define HVC_CONSOLE_H
29#include <linux/kref.h>
30#include <linux/tty.h>
31#include <linux/spinlock.h>
32
33/*
34 * This is the max number of console adapters that can/will be found as
35 * console devices on first stage console init. Any number beyond this range
36 * can't be used as a console device but is still a valid tty device.
37 */
38#define MAX_NR_HVC_CONSOLES 16
39
40/*
41 * The Linux TTY code does not support dynamic addition of tty derived devices
42 * so we need to know how many tty devices we might need when space is allocated
43 * for the tty device. Since this driver supports hotplug of vty adapters we
44 * need to make sure we have enough allocated.
45 */
46#define HVC_ALLOC_TTY_ADAPTERS 8
47
48struct hvc_struct {
49 spinlock_t lock;
50 int index;
51 struct tty_struct *tty;
52 int count;
53 int do_wakeup;
54 char *outbuf;
55 int outbuf_size;
56 int n_outbuf;
57 uint32_t vtermno;
58 const struct hv_ops *ops;
59 int irq_requested;
60 int data;
61 struct winsize ws;
62 struct work_struct tty_resize;
63 struct list_head next;
64 struct kref kref; /* ref count & hvc_struct lifetime */
65};
66
67/* implemented by a low level driver */
68struct hv_ops {
69 int (*get_chars)(uint32_t vtermno, char *buf, int count);
70 int (*put_chars)(uint32_t vtermno, const char *buf, int count);
71
72 /* Callbacks for notification. Called in open, close and hangup */
73 int (*notifier_add)(struct hvc_struct *hp, int irq);
74 void (*notifier_del)(struct hvc_struct *hp, int irq);
75 void (*notifier_hangup)(struct hvc_struct *hp, int irq);
76};
77
78/* Register a vterm and a slot index for use as a console (console_init) */
79extern int hvc_instantiate(uint32_t vtermno, int index,
80 const struct hv_ops *ops);
81
82/* register a vterm for hvc tty operation (module_init or hotplug add) */
83extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
84 const struct hv_ops *ops, int outbuf_size);
85/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
86extern int hvc_remove(struct hvc_struct *hp);
87
88/* data available */
89int hvc_poll(struct hvc_struct *hp);
90void hvc_kick(void);
91
92/* Resize hvc tty terminal window */
93extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
94
95static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
96{
97 unsigned long flags;
98
99 spin_lock_irqsave(&hp->lock, flags);
100 __hvc_resize(hp, ws);
101 spin_unlock_irqrestore(&hp->lock, flags);
102}
103
104/* default notifier for irq based notification */
105extern int notifier_add_irq(struct hvc_struct *hp, int data);
106extern void notifier_del_irq(struct hvc_struct *hp, int data);
107extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
108
109
110#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
111#include <asm/xmon.h>
112#else
113static inline int cpus_are_in_xmon(void)
114{
115 return 0;
116}
117#endif
118
119#endif // HVC_CONSOLE_H
diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c
new file mode 100644
index 000000000000..6470f63deb4b
--- /dev/null
+++ b/drivers/tty/hvc/hvc_dcc.c
@@ -0,0 +1,133 @@
1/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License version 2 and
5 * only version 2 as published by the Free Software Foundation.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
15 * 02110-1301, USA.
16 */
17
18#include <linux/console.h>
19#include <linux/delay.h>
20#include <linux/err.h>
21#include <linux/init.h>
22#include <linux/moduleparam.h>
23#include <linux/types.h>
24
25#include <asm/processor.h>
26
27#include "hvc_console.h"
28
29/* DCC Status Bits */
30#define DCC_STATUS_RX (1 << 30)
31#define DCC_STATUS_TX (1 << 29)
32
33static inline u32 __dcc_getstatus(void)
34{
35 u32 __ret;
36
37 asm("mrc p14, 0, %0, c0, c1, 0 @ read comms ctrl reg"
38 : "=r" (__ret) : : "cc");
39
40 return __ret;
41}
42
43
44#if defined(CONFIG_CPU_V7)
45static inline char __dcc_getchar(void)
46{
47 char __c;
48
49 asm("get_wait: mrc p14, 0, pc, c0, c1, 0 \n\
50 bne get_wait \n\
51 mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
52 : "=r" (__c) : : "cc");
53
54 return __c;
55}
56#else
57static inline char __dcc_getchar(void)
58{
59 char __c;
60
61 asm("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
62 : "=r" (__c));
63
64 return __c;
65}
66#endif
67
68#if defined(CONFIG_CPU_V7)
69static inline void __dcc_putchar(char c)
70{
71 asm("put_wait: mrc p14, 0, pc, c0, c1, 0 \n\
72 bcs put_wait \n\
73 mcr p14, 0, %0, c0, c5, 0 "
74 : : "r" (c) : "cc");
75}
76#else
77static inline void __dcc_putchar(char c)
78{
79 asm("mcr p14, 0, %0, c0, c5, 0 @ write a char"
80 : /* no output register */
81 : "r" (c));
82}
83#endif
84
85static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
86{
87 int i;
88
89 for (i = 0; i < count; i++) {
90 while (__dcc_getstatus() & DCC_STATUS_TX)
91 cpu_relax();
92
93 __dcc_putchar((char)(buf[i] & 0xFF));
94 }
95
96 return count;
97}
98
99static int hvc_dcc_get_chars(uint32_t vt, char *buf, int count)
100{
101 int i;
102
103 for (i = 0; i < count; ++i) {
104 int c = -1;
105
106 if (__dcc_getstatus() & DCC_STATUS_RX)
107 c = __dcc_getchar();
108 if (c < 0)
109 break;
110 buf[i] = c;
111 }
112
113 return i;
114}
115
116static const struct hv_ops hvc_dcc_get_put_ops = {
117 .get_chars = hvc_dcc_get_chars,
118 .put_chars = hvc_dcc_put_chars,
119};
120
121static int __init hvc_dcc_console_init(void)
122{
123 hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
124 return 0;
125}
126console_initcall(hvc_dcc_console_init);
127
128static int __init hvc_dcc_init(void)
129{
130 hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
131 return 0;
132}
133device_initcall(hvc_dcc_init);
diff --git a/drivers/tty/hvc/hvc_irq.c b/drivers/tty/hvc/hvc_irq.c
new file mode 100644
index 000000000000..2623e177e8d6
--- /dev/null
+++ b/drivers/tty/hvc/hvc_irq.c
@@ -0,0 +1,49 @@
1/*
2 * Copyright IBM Corp. 2001,2008
3 *
4 * This file contains the IRQ specific code for hvc_console
5 *
6 */
7
8#include <linux/interrupt.h>
9
10#include "hvc_console.h"
11
12static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance)
13{
14 /* if hvc_poll request a repoll, then kick the hvcd thread */
15 if (hvc_poll(dev_instance))
16 hvc_kick();
17 return IRQ_HANDLED;
18}
19
20/*
21 * For IRQ based systems these callbacks can be used
22 */
23int notifier_add_irq(struct hvc_struct *hp, int irq)
24{
25 int rc;
26
27 if (!irq) {
28 hp->irq_requested = 0;
29 return 0;
30 }
31 rc = request_irq(irq, hvc_handle_interrupt, IRQF_DISABLED,
32 "hvc_console", hp);
33 if (!rc)
34 hp->irq_requested = 1;
35 return rc;
36}
37
38void notifier_del_irq(struct hvc_struct *hp, int irq)
39{
40 if (!hp->irq_requested)
41 return;
42 free_irq(irq, hp);
43 hp->irq_requested = 0;
44}
45
46void notifier_hangup_irq(struct hvc_struct *hp, int irq)
47{
48 notifier_del_irq(hp, irq);
49}
diff --git a/drivers/tty/hvc/hvc_iseries.c b/drivers/tty/hvc/hvc_iseries.c
new file mode 100644
index 000000000000..21c54955084e
--- /dev/null
+++ b/drivers/tty/hvc/hvc_iseries.c
@@ -0,0 +1,598 @@
1/*
2 * iSeries vio driver interface to hvc_console.c
3 *
4 * This code is based heavily on hvc_vio.c and viocons.c
5 *
6 * Copyright (C) 2006 Stephen Rothwell, IBM Corporation
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22#include <stdarg.h>
23#include <linux/types.h>
24#include <linux/init.h>
25#include <linux/kernel.h>
26#include <linux/spinlock.h>
27#include <linux/console.h>
28
29#include <asm/hvconsole.h>
30#include <asm/vio.h>
31#include <asm/prom.h>
32#include <asm/firmware.h>
33#include <asm/iseries/vio.h>
34#include <asm/iseries/hv_call.h>
35#include <asm/iseries/hv_lp_config.h>
36#include <asm/iseries/hv_lp_event.h>
37
38#include "hvc_console.h"
39
40#define VTTY_PORTS 10
41
42static DEFINE_SPINLOCK(consolelock);
43static DEFINE_SPINLOCK(consoleloglock);
44
45static const char hvc_driver_name[] = "hvc_console";
46
47#define IN_BUF_SIZE 200
48
49/*
50 * Our port information.
51 */
52static struct port_info {
53 HvLpIndex lp;
54 u64 seq; /* sequence number of last HV send */
55 u64 ack; /* last ack from HV */
56 struct hvc_struct *hp;
57 int in_start;
58 int in_end;
59 unsigned char in_buf[IN_BUF_SIZE];
60} port_info[VTTY_PORTS] = {
61 [ 0 ... VTTY_PORTS - 1 ] = {
62 .lp = HvLpIndexInvalid
63 }
64};
65
66#define viochar_is_console(pi) ((pi) == &port_info[0])
67
68static struct vio_device_id hvc_driver_table[] __devinitdata = {
69 {"serial", "IBM,iSeries-vty"},
70 { "", "" }
71};
72MODULE_DEVICE_TABLE(vio, hvc_driver_table);
73
74static void hvlog(char *fmt, ...)
75{
76 int i;
77 unsigned long flags;
78 va_list args;
79 static char buf[256];
80
81 spin_lock_irqsave(&consoleloglock, flags);
82 va_start(args, fmt);
83 i = vscnprintf(buf, sizeof(buf) - 1, fmt, args);
84 va_end(args);
85 buf[i++] = '\r';
86 HvCall_writeLogBuffer(buf, i);
87 spin_unlock_irqrestore(&consoleloglock, flags);
88}
89
90/*
91 * Initialize the common fields in a charLpEvent
92 */
93static void init_data_event(struct viocharlpevent *viochar, HvLpIndex lp)
94{
95 struct HvLpEvent *hev = &viochar->event;
96
97 memset(viochar, 0, sizeof(struct viocharlpevent));
98
99 hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DEFERRED_ACK |
100 HV_LP_EVENT_INT;
101 hev->xType = HvLpEvent_Type_VirtualIo;
102 hev->xSubtype = viomajorsubtype_chario | viochardata;
103 hev->xSourceLp = HvLpConfig_getLpIndex();
104 hev->xTargetLp = lp;
105 hev->xSizeMinus1 = sizeof(struct viocharlpevent);
106 hev->xSourceInstanceId = viopath_sourceinst(lp);
107 hev->xTargetInstanceId = viopath_targetinst(lp);
108}
109
110static int get_chars(uint32_t vtermno, char *buf, int count)
111{
112 struct port_info *pi;
113 int n = 0;
114 unsigned long flags;
115
116 if (vtermno >= VTTY_PORTS)
117 return -EINVAL;
118 if (count == 0)
119 return 0;
120
121 pi = &port_info[vtermno];
122 spin_lock_irqsave(&consolelock, flags);
123
124 if (pi->in_end == 0)
125 goto done;
126
127 n = pi->in_end - pi->in_start;
128 if (n > count)
129 n = count;
130 memcpy(buf, &pi->in_buf[pi->in_start], n);
131 pi->in_start += n;
132 if (pi->in_start == pi->in_end) {
133 pi->in_start = 0;
134 pi->in_end = 0;
135 }
136done:
137 spin_unlock_irqrestore(&consolelock, flags);
138 return n;
139}
140
141static int put_chars(uint32_t vtermno, const char *buf, int count)
142{
143 struct viocharlpevent *viochar;
144 struct port_info *pi;
145 HvLpEvent_Rc hvrc;
146 unsigned long flags;
147 int sent = 0;
148
149 if (vtermno >= VTTY_PORTS)
150 return -EINVAL;
151
152 pi = &port_info[vtermno];
153
154 spin_lock_irqsave(&consolelock, flags);
155
156 if (viochar_is_console(pi) && !viopath_isactive(pi->lp)) {
157 HvCall_writeLogBuffer(buf, count);
158 sent = count;
159 goto done;
160 }
161
162 viochar = vio_get_event_buffer(viomajorsubtype_chario);
163 if (viochar == NULL) {
164 hvlog("\n\rviocons: Can't get viochar buffer.");
165 goto done;
166 }
167
168 while ((count > 0) && ((pi->seq - pi->ack) < VIOCHAR_WINDOW)) {
169 int len;
170
171 len = (count > VIOCHAR_MAX_DATA) ? VIOCHAR_MAX_DATA : count;
172
173 if (viochar_is_console(pi))
174 HvCall_writeLogBuffer(buf, len);
175
176 init_data_event(viochar, pi->lp);
177
178 viochar->len = len;
179 viochar->event.xCorrelationToken = pi->seq++;
180 viochar->event.xSizeMinus1 =
181 offsetof(struct viocharlpevent, data) + len;
182
183 memcpy(viochar->data, buf, len);
184
185 hvrc = HvCallEvent_signalLpEvent(&viochar->event);
186 if (hvrc)
187 hvlog("\n\rerror sending event! return code %d\n\r",
188 (int)hvrc);
189 sent += len;
190 count -= len;
191 buf += len;
192 }
193
194 vio_free_event_buffer(viomajorsubtype_chario, viochar);
195done:
196 spin_unlock_irqrestore(&consolelock, flags);
197 return sent;
198}
199
200static const struct hv_ops hvc_get_put_ops = {
201 .get_chars = get_chars,
202 .put_chars = put_chars,
203 .notifier_add = notifier_add_irq,
204 .notifier_del = notifier_del_irq,
205 .notifier_hangup = notifier_hangup_irq,
206};
207
208static int __devinit hvc_vio_probe(struct vio_dev *vdev,
209 const struct vio_device_id *id)
210{
211 struct hvc_struct *hp;
212 struct port_info *pi;
213
214 /* probed with invalid parameters. */
215 if (!vdev || !id)
216 return -EPERM;
217
218 if (vdev->unit_address >= VTTY_PORTS)
219 return -ENODEV;
220
221 pi = &port_info[vdev->unit_address];
222
223 hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
224 VIOCHAR_MAX_DATA);
225 if (IS_ERR(hp))
226 return PTR_ERR(hp);
227 pi->hp = hp;
228 dev_set_drvdata(&vdev->dev, pi);
229
230 return 0;
231}
232
233static int __devexit hvc_vio_remove(struct vio_dev *vdev)
234{
235 struct port_info *pi = dev_get_drvdata(&vdev->dev);
236 struct hvc_struct *hp = pi->hp;
237
238 return hvc_remove(hp);
239}
240
241static struct vio_driver hvc_vio_driver = {
242 .id_table = hvc_driver_table,
243 .probe = hvc_vio_probe,
244 .remove = __devexit_p(hvc_vio_remove),
245 .driver = {
246 .name = hvc_driver_name,
247 .owner = THIS_MODULE,
248 }
249};
250
251static void hvc_open_event(struct HvLpEvent *event)
252{
253 unsigned long flags;
254 struct viocharlpevent *cevent = (struct viocharlpevent *)event;
255 u8 port = cevent->virtual_device;
256 struct port_info *pi;
257 int reject = 0;
258
259 if (hvlpevent_is_ack(event)) {
260 if (port >= VTTY_PORTS)
261 return;
262
263 spin_lock_irqsave(&consolelock, flags);
264
265 pi = &port_info[port];
266 if (event->xRc == HvLpEvent_Rc_Good) {
267 pi->seq = pi->ack = 0;
268 /*
269 * This line allows connections from the primary
270 * partition but once one is connected from the
271 * primary partition nothing short of a reboot
272 * of linux will allow access from the hosting
273 * partition again without a required iSeries fix.
274 */
275 pi->lp = event->xTargetLp;
276 }
277
278 spin_unlock_irqrestore(&consolelock, flags);
279 if (event->xRc != HvLpEvent_Rc_Good)
280 printk(KERN_WARNING
281 "hvc: handle_open_event: event->xRc == (%d).\n",
282 event->xRc);
283
284 if (event->xCorrelationToken != 0) {
285 atomic_t *aptr= (atomic_t *)event->xCorrelationToken;
286 atomic_set(aptr, 1);
287 } else
288 printk(KERN_WARNING
289 "hvc: weird...got open ack without atomic\n");
290 return;
291 }
292
293 /* This had better require an ack, otherwise complain */
294 if (!hvlpevent_need_ack(event)) {
295 printk(KERN_WARNING "hvc: viocharopen without ack bit!\n");
296 return;
297 }
298
299 spin_lock_irqsave(&consolelock, flags);
300
301 /* Make sure this is a good virtual tty */
302 if (port >= VTTY_PORTS) {
303 event->xRc = HvLpEvent_Rc_SubtypeError;
304 cevent->subtype_result_code = viorc_openRejected;
305 /*
306 * Flag state here since we can't printk while holding
307 * the consolelock spinlock.
308 */
309 reject = 1;
310 } else {
311 pi = &port_info[port];
312 if ((pi->lp != HvLpIndexInvalid) &&
313 (pi->lp != event->xSourceLp)) {
314 /*
315 * If this is tty is already connected to a different
316 * partition, fail.
317 */
318 event->xRc = HvLpEvent_Rc_SubtypeError;
319 cevent->subtype_result_code = viorc_openRejected;
320 reject = 2;
321 } else {
322 pi->lp = event->xSourceLp;
323 event->xRc = HvLpEvent_Rc_Good;
324 cevent->subtype_result_code = viorc_good;
325 pi->seq = pi->ack = 0;
326 }
327 }
328
329 spin_unlock_irqrestore(&consolelock, flags);
330
331 if (reject == 1)
332 printk(KERN_WARNING "hvc: open rejected: bad virtual tty.\n");
333 else if (reject == 2)
334 printk(KERN_WARNING "hvc: open rejected: console in exclusive "
335 "use by another partition.\n");
336
337 /* Return the acknowledgement */
338 HvCallEvent_ackLpEvent(event);
339}
340
341/*
342 * Handle a close charLpEvent. This should ONLY be an Interrupt because the
343 * virtual console should never actually issue a close event to the hypervisor
344 * because the virtual console never goes away. A close event coming from the
345 * hypervisor simply means that there are no client consoles connected to the
346 * virtual console.
347 */
348static void hvc_close_event(struct HvLpEvent *event)
349{
350 unsigned long flags;
351 struct viocharlpevent *cevent = (struct viocharlpevent *)event;
352 u8 port = cevent->virtual_device;
353
354 if (!hvlpevent_is_int(event)) {
355 printk(KERN_WARNING
356 "hvc: got unexpected close acknowledgement\n");
357 return;
358 }
359
360 if (port >= VTTY_PORTS) {
361 printk(KERN_WARNING
362 "hvc: close message from invalid virtual device.\n");
363 return;
364 }
365
366 /* For closes, just mark the console partition invalid */
367 spin_lock_irqsave(&consolelock, flags);
368
369 if (port_info[port].lp == event->xSourceLp)
370 port_info[port].lp = HvLpIndexInvalid;
371
372 spin_unlock_irqrestore(&consolelock, flags);
373}
374
375static void hvc_data_event(struct HvLpEvent *event)
376{
377 unsigned long flags;
378 struct viocharlpevent *cevent = (struct viocharlpevent *)event;
379 struct port_info *pi;
380 int n;
381 u8 port = cevent->virtual_device;
382
383 if (port >= VTTY_PORTS) {
384 printk(KERN_WARNING "hvc: data on invalid virtual device %d\n",
385 port);
386 return;
387 }
388 if (cevent->len == 0)
389 return;
390
391 /*
392 * Change 05/01/2003 - Ryan Arnold: If a partition other than
393 * the current exclusive partition tries to send us data
394 * events then just drop them on the floor because we don't
395 * want his stinking data. He isn't authorized to receive
396 * data because he wasn't the first one to get the console,
397 * therefore he shouldn't be allowed to send data either.
398 * This will work without an iSeries fix.
399 */
400 pi = &port_info[port];
401 if (pi->lp != event->xSourceLp)
402 return;
403
404 spin_lock_irqsave(&consolelock, flags);
405
406 n = IN_BUF_SIZE - pi->in_end;
407 if (n > cevent->len)
408 n = cevent->len;
409 if (n > 0) {
410 memcpy(&pi->in_buf[pi->in_end], cevent->data, n);
411 pi->in_end += n;
412 }
413 spin_unlock_irqrestore(&consolelock, flags);
414 if (n == 0)
415 printk(KERN_WARNING "hvc: input buffer overflow\n");
416}
417
418static void hvc_ack_event(struct HvLpEvent *event)
419{
420 struct viocharlpevent *cevent = (struct viocharlpevent *)event;
421 unsigned long flags;
422 u8 port = cevent->virtual_device;
423
424 if (port >= VTTY_PORTS) {
425 printk(KERN_WARNING "hvc: data on invalid virtual device\n");
426 return;
427 }
428
429 spin_lock_irqsave(&consolelock, flags);
430 port_info[port].ack = event->xCorrelationToken;
431 spin_unlock_irqrestore(&consolelock, flags);
432}
433
434static void hvc_config_event(struct HvLpEvent *event)
435{
436 struct viocharlpevent *cevent = (struct viocharlpevent *)event;
437
438 if (cevent->data[0] == 0x01)
439 printk(KERN_INFO "hvc: window resized to %d: %d: %d: %d\n",
440 cevent->data[1], cevent->data[2],
441 cevent->data[3], cevent->data[4]);
442 else
443 printk(KERN_WARNING "hvc: unknown config event\n");
444}
445
446static void hvc_handle_event(struct HvLpEvent *event)
447{
448 int charminor;
449
450 if (event == NULL)
451 return;
452
453 charminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
454 switch (charminor) {
455 case viocharopen:
456 hvc_open_event(event);
457 break;
458 case viocharclose:
459 hvc_close_event(event);
460 break;
461 case viochardata:
462 hvc_data_event(event);
463 break;
464 case viocharack:
465 hvc_ack_event(event);
466 break;
467 case viocharconfig:
468 hvc_config_event(event);
469 break;
470 default:
471 if (hvlpevent_is_int(event) && hvlpevent_need_ack(event)) {
472 event->xRc = HvLpEvent_Rc_InvalidSubtype;
473 HvCallEvent_ackLpEvent(event);
474 }
475 }
476}
477
478static int __init send_open(HvLpIndex remoteLp, void *sem)
479{
480 return HvCallEvent_signalLpEventFast(remoteLp,
481 HvLpEvent_Type_VirtualIo,
482 viomajorsubtype_chario | viocharopen,
483 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
484 viopath_sourceinst(remoteLp),
485 viopath_targetinst(remoteLp),
486 (u64)(unsigned long)sem, VIOVERSION << 16,
487 0, 0, 0, 0);
488}
489
490static int __init hvc_vio_init(void)
491{
492 atomic_t wait_flag;
493 int rc;
494
495 if (!firmware_has_feature(FW_FEATURE_ISERIES))
496 return -EIO;
497
498 /* +2 for fudge */
499 rc = viopath_open(HvLpConfig_getPrimaryLpIndex(),
500 viomajorsubtype_chario, VIOCHAR_WINDOW + 2);
501 if (rc)
502 printk(KERN_WARNING "hvc: error opening to primary %d\n", rc);
503
504 if (viopath_hostLp == HvLpIndexInvalid)
505 vio_set_hostlp();
506
507 /*
508 * And if the primary is not the same as the hosting LP, open to the
509 * hosting lp
510 */
511 if ((viopath_hostLp != HvLpIndexInvalid) &&
512 (viopath_hostLp != HvLpConfig_getPrimaryLpIndex())) {
513 printk(KERN_INFO "hvc: open path to hosting (%d)\n",
514 viopath_hostLp);
515 rc = viopath_open(viopath_hostLp, viomajorsubtype_chario,
516 VIOCHAR_WINDOW + 2); /* +2 for fudge */
517 if (rc)
518 printk(KERN_WARNING
519 "error opening to partition %d: %d\n",
520 viopath_hostLp, rc);
521 }
522
523 if (vio_setHandler(viomajorsubtype_chario, hvc_handle_event) < 0)
524 printk(KERN_WARNING
525 "hvc: error seting handler for console events!\n");
526
527 /*
528 * First, try to open the console to the hosting lp.
529 * Wait on a semaphore for the response.
530 */
531 atomic_set(&wait_flag, 0);
532 if ((viopath_isactive(viopath_hostLp)) &&
533 (send_open(viopath_hostLp, &wait_flag) == 0)) {
534 printk(KERN_INFO "hvc: hosting partition %d\n", viopath_hostLp);
535 while (atomic_read(&wait_flag) == 0)
536 mb();
537 atomic_set(&wait_flag, 0);
538 }
539
540 /*
541 * If we don't have an active console, try the primary
542 */
543 if ((!viopath_isactive(port_info[0].lp)) &&
544 (viopath_isactive(HvLpConfig_getPrimaryLpIndex())) &&
545 (send_open(HvLpConfig_getPrimaryLpIndex(), &wait_flag) == 0)) {
546 printk(KERN_INFO "hvc: opening console to primary partition\n");
547 while (atomic_read(&wait_flag) == 0)
548 mb();
549 }
550
551 /* Register as a vio device to receive callbacks */
552 rc = vio_register_driver(&hvc_vio_driver);
553
554 return rc;
555}
556module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
557
558static void __exit hvc_vio_exit(void)
559{
560 vio_unregister_driver(&hvc_vio_driver);
561}
562module_exit(hvc_vio_exit);
563
564/* the device tree order defines our numbering */
565static int __init hvc_find_vtys(void)
566{
567 struct device_node *vty;
568 int num_found = 0;
569
570 for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
571 vty = of_find_node_by_name(vty, "vty")) {
572 const uint32_t *vtermno;
573
574 /* We have statically defined space for only a certain number
575 * of console adapters.
576 */
577 if ((num_found >= MAX_NR_HVC_CONSOLES) ||
578 (num_found >= VTTY_PORTS)) {
579 of_node_put(vty);
580 break;
581 }
582
583 vtermno = of_get_property(vty, "reg", NULL);
584 if (!vtermno)
585 continue;
586
587 if (!of_device_is_compatible(vty, "IBM,iSeries-vty"))
588 continue;
589
590 if (num_found == 0)
591 add_preferred_console("hvc", 0, NULL);
592 hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
593 ++num_found;
594 }
595
596 return num_found;
597}
598console_initcall(hvc_find_vtys);
diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c
new file mode 100644
index 000000000000..c3425bb3a1f6
--- /dev/null
+++ b/drivers/tty/hvc/hvc_iucv.c
@@ -0,0 +1,1337 @@
1/*
2 * hvc_iucv.c - z/VM IUCV hypervisor console (HVC) device driver
3 *
4 * This HVC device driver provides terminal access using
5 * z/VM IUCV communication paths.
6 *
7 * Copyright IBM Corp. 2008, 2009
8 *
9 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
10 */
11#define KMSG_COMPONENT "hvc_iucv"
12#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14#include <linux/types.h>
15#include <linux/slab.h>
16#include <asm/ebcdic.h>
17#include <linux/ctype.h>
18#include <linux/delay.h>
19#include <linux/device.h>
20#include <linux/init.h>
21#include <linux/mempool.h>
22#include <linux/moduleparam.h>
23#include <linux/tty.h>
24#include <linux/wait.h>
25#include <net/iucv/iucv.h>
26
27#include "hvc_console.h"
28
29
30/* General device driver settings */
31#define HVC_IUCV_MAGIC 0xc9e4c3e5
32#define MAX_HVC_IUCV_LINES HVC_ALLOC_TTY_ADAPTERS
33#define MEMPOOL_MIN_NR (PAGE_SIZE / sizeof(struct iucv_tty_buffer)/4)
34
35/* IUCV TTY message */
36#define MSG_VERSION 0x02 /* Message version */
37#define MSG_TYPE_ERROR 0x01 /* Error message */
38#define MSG_TYPE_TERMENV 0x02 /* Terminal environment variable */
39#define MSG_TYPE_TERMIOS 0x04 /* Terminal IO struct update */
40#define MSG_TYPE_WINSIZE 0x08 /* Terminal window size update */
41#define MSG_TYPE_DATA 0x10 /* Terminal data */
42
43struct iucv_tty_msg {
44 u8 version; /* Message version */
45 u8 type; /* Message type */
46#define MSG_MAX_DATALEN ((u16)(~0))
47 u16 datalen; /* Payload length */
48 u8 data[]; /* Payload buffer */
49} __attribute__((packed));
50#define MSG_SIZE(s) ((s) + offsetof(struct iucv_tty_msg, data))
51
52enum iucv_state_t {
53 IUCV_DISCONN = 0,
54 IUCV_CONNECTED = 1,
55 IUCV_SEVERED = 2,
56};
57
58enum tty_state_t {
59 TTY_CLOSED = 0,
60 TTY_OPENED = 1,
61};
62
63struct hvc_iucv_private {
64 struct hvc_struct *hvc; /* HVC struct reference */
65 u8 srv_name[8]; /* IUCV service name (ebcdic) */
66 unsigned char is_console; /* Linux console usage flag */
67 enum iucv_state_t iucv_state; /* IUCV connection status */
68 enum tty_state_t tty_state; /* TTY status */
69 struct iucv_path *path; /* IUCV path pointer */
70 spinlock_t lock; /* hvc_iucv_private lock */
71#define SNDBUF_SIZE (PAGE_SIZE) /* must be < MSG_MAX_DATALEN */
72 void *sndbuf; /* send buffer */
73 size_t sndbuf_len; /* length of send buffer */
74#define QUEUE_SNDBUF_DELAY (HZ / 25)
75 struct delayed_work sndbuf_work; /* work: send iucv msg(s) */
76 wait_queue_head_t sndbuf_waitq; /* wait for send completion */
77 struct list_head tty_outqueue; /* outgoing IUCV messages */
78 struct list_head tty_inqueue; /* incoming IUCV messages */
79 struct device *dev; /* device structure */
80};
81
82struct iucv_tty_buffer {
83 struct list_head list; /* list pointer */
84 struct iucv_message msg; /* store an IUCV message */
85 size_t offset; /* data buffer offset */
86 struct iucv_tty_msg *mbuf; /* buffer to store input/output data */
87};
88
89/* IUCV callback handler */
90static int hvc_iucv_path_pending(struct iucv_path *, u8[8], u8[16]);
91static void hvc_iucv_path_severed(struct iucv_path *, u8[16]);
92static void hvc_iucv_msg_pending(struct iucv_path *, struct iucv_message *);
93static void hvc_iucv_msg_complete(struct iucv_path *, struct iucv_message *);
94
95
96/* Kernel module parameter: use one terminal device as default */
97static unsigned long hvc_iucv_devices = 1;
98
99/* Array of allocated hvc iucv tty lines... */
100static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES];
101#define IUCV_HVC_CON_IDX (0)
102/* List of z/VM user ID filter entries (struct iucv_vmid_filter) */
103#define MAX_VMID_FILTER (500)
104static size_t hvc_iucv_filter_size;
105static void *hvc_iucv_filter;
106static const char *hvc_iucv_filter_string;
107static DEFINE_RWLOCK(hvc_iucv_filter_lock);
108
109/* Kmem cache and mempool for iucv_tty_buffer elements */
110static struct kmem_cache *hvc_iucv_buffer_cache;
111static mempool_t *hvc_iucv_mempool;
112
113/* IUCV handler callback functions */
114static struct iucv_handler hvc_iucv_handler = {
115 .path_pending = hvc_iucv_path_pending,
116 .path_severed = hvc_iucv_path_severed,
117 .message_complete = hvc_iucv_msg_complete,
118 .message_pending = hvc_iucv_msg_pending,
119};
120
121
122/**
123 * hvc_iucv_get_private() - Return a struct hvc_iucv_private instance.
124 * @num: The HVC virtual terminal number (vtermno)
125 *
126 * This function returns the struct hvc_iucv_private instance that corresponds
127 * to the HVC virtual terminal number specified as parameter @num.
128 */
129struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num)
130{
131 if ((num < HVC_IUCV_MAGIC) || (num - HVC_IUCV_MAGIC > hvc_iucv_devices))
132 return NULL;
133 return hvc_iucv_table[num - HVC_IUCV_MAGIC];
134}
135
136/**
137 * alloc_tty_buffer() - Return a new struct iucv_tty_buffer element.
138 * @size: Size of the internal buffer used to store data.
139 * @flags: Memory allocation flags passed to mempool.
140 *
141 * This function allocates a new struct iucv_tty_buffer element and, optionally,
142 * allocates an internal data buffer with the specified size @size.
143 * The internal data buffer is always allocated with GFP_DMA which is
144 * required for receiving and sending data with IUCV.
145 * Note: The total message size arises from the internal buffer size and the
146 * members of the iucv_tty_msg structure.
147 * The function returns NULL if memory allocation has failed.
148 */
149static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags)
150{
151 struct iucv_tty_buffer *bufp;
152
153 bufp = mempool_alloc(hvc_iucv_mempool, flags);
154 if (!bufp)
155 return NULL;
156 memset(bufp, 0, sizeof(*bufp));
157
158 if (size > 0) {
159 bufp->msg.length = MSG_SIZE(size);
160 bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA);
161 if (!bufp->mbuf) {
162 mempool_free(bufp, hvc_iucv_mempool);
163 return NULL;
164 }
165 bufp->mbuf->version = MSG_VERSION;
166 bufp->mbuf->type = MSG_TYPE_DATA;
167 bufp->mbuf->datalen = (u16) size;
168 }
169 return bufp;
170}
171
172/**
173 * destroy_tty_buffer() - destroy struct iucv_tty_buffer element.
174 * @bufp: Pointer to a struct iucv_tty_buffer element, SHALL NOT be NULL.
175 */
176static void destroy_tty_buffer(struct iucv_tty_buffer *bufp)
177{
178 kfree(bufp->mbuf);
179 mempool_free(bufp, hvc_iucv_mempool);
180}
181
182/**
183 * destroy_tty_buffer_list() - call destroy_tty_buffer() for each list element.
184 * @list: List containing struct iucv_tty_buffer elements.
185 */
186static void destroy_tty_buffer_list(struct list_head *list)
187{
188 struct iucv_tty_buffer *ent, *next;
189
190 list_for_each_entry_safe(ent, next, list, list) {
191 list_del(&ent->list);
192 destroy_tty_buffer(ent);
193 }
194}
195
196/**
197 * hvc_iucv_write() - Receive IUCV message & write data to HVC buffer.
198 * @priv: Pointer to struct hvc_iucv_private
199 * @buf: HVC buffer for writing received terminal data.
200 * @count: HVC buffer size.
201 * @has_more_data: Pointer to an int variable.
202 *
203 * The function picks up pending messages from the input queue and receives
204 * the message data that is then written to the specified buffer @buf.
205 * If the buffer size @count is less than the data message size, the
206 * message is kept on the input queue and @has_more_data is set to 1.
207 * If all message data has been written, the message is removed from
208 * the input queue.
209 *
210 * The function returns the number of bytes written to the terminal, zero if
211 * there are no pending data messages available or if there is no established
212 * IUCV path.
213 * If the IUCV path has been severed, then -EPIPE is returned to cause a
214 * hang up (that is issued by the HVC layer).
215 */
216static int hvc_iucv_write(struct hvc_iucv_private *priv,
217 char *buf, int count, int *has_more_data)
218{
219 struct iucv_tty_buffer *rb;
220 int written;
221 int rc;
222
223 /* immediately return if there is no IUCV connection */
224 if (priv->iucv_state == IUCV_DISCONN)
225 return 0;
226
227 /* if the IUCV path has been severed, return -EPIPE to inform the
228 * HVC layer to hang up the tty device. */
229 if (priv->iucv_state == IUCV_SEVERED)
230 return -EPIPE;
231
232 /* check if there are pending messages */
233 if (list_empty(&priv->tty_inqueue))
234 return 0;
235
236 /* receive an iucv message and flip data to the tty (ldisc) */
237 rb = list_first_entry(&priv->tty_inqueue, struct iucv_tty_buffer, list);
238
239 written = 0;
240 if (!rb->mbuf) { /* message not yet received ... */
241 /* allocate mem to store msg data; if no memory is available
242 * then leave the buffer on the list and re-try later */
243 rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA);
244 if (!rb->mbuf)
245 return -ENOMEM;
246
247 rc = __iucv_message_receive(priv->path, &rb->msg, 0,
248 rb->mbuf, rb->msg.length, NULL);
249 switch (rc) {
250 case 0: /* Successful */
251 break;
252 case 2: /* No message found */
253 case 9: /* Message purged */
254 break;
255 default:
256 written = -EIO;
257 }
258 /* remove buffer if an error has occured or received data
259 * is not correct */
260 if (rc || (rb->mbuf->version != MSG_VERSION) ||
261 (rb->msg.length != MSG_SIZE(rb->mbuf->datalen)))
262 goto out_remove_buffer;
263 }
264
265 switch (rb->mbuf->type) {
266 case MSG_TYPE_DATA:
267 written = min_t(int, rb->mbuf->datalen - rb->offset, count);
268 memcpy(buf, rb->mbuf->data + rb->offset, written);
269 if (written < (rb->mbuf->datalen - rb->offset)) {
270 rb->offset += written;
271 *has_more_data = 1;
272 goto out_written;
273 }
274 break;
275
276 case MSG_TYPE_WINSIZE:
277 if (rb->mbuf->datalen != sizeof(struct winsize))
278 break;
279 /* The caller must ensure that the hvc is locked, which
280 * is the case when called from hvc_iucv_get_chars() */
281 __hvc_resize(priv->hvc, *((struct winsize *) rb->mbuf->data));
282 break;
283
284 case MSG_TYPE_ERROR: /* ignored ... */
285 case MSG_TYPE_TERMENV: /* ignored ... */
286 case MSG_TYPE_TERMIOS: /* ignored ... */
287 break;
288 }
289
290out_remove_buffer:
291 list_del(&rb->list);
292 destroy_tty_buffer(rb);
293 *has_more_data = !list_empty(&priv->tty_inqueue);
294
295out_written:
296 return written;
297}
298
299/**
300 * hvc_iucv_get_chars() - HVC get_chars operation.
301 * @vtermno: HVC virtual terminal number.
302 * @buf: Pointer to a buffer to store data
303 * @count: Size of buffer available for writing
304 *
305 * The HVC thread calls this method to read characters from the back-end.
306 * If an IUCV communication path has been established, pending IUCV messages
307 * are received and data is copied into buffer @buf up to @count bytes.
308 *
309 * Locking: The routine gets called under an irqsave() spinlock; and
310 * the routine locks the struct hvc_iucv_private->lock to call
311 * helper functions.
312 */
313static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count)
314{
315 struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
316 int written;
317 int has_more_data;
318
319 if (count <= 0)
320 return 0;
321
322 if (!priv)
323 return -ENODEV;
324
325 spin_lock(&priv->lock);
326 has_more_data = 0;
327 written = hvc_iucv_write(priv, buf, count, &has_more_data);
328 spin_unlock(&priv->lock);
329
330 /* if there are still messages on the queue... schedule another run */
331 if (has_more_data)
332 hvc_kick();
333
334 return written;
335}
336
337/**
338 * hvc_iucv_queue() - Buffer terminal data for sending.
339 * @priv: Pointer to struct hvc_iucv_private instance.
340 * @buf: Buffer containing data to send.
341 * @count: Size of buffer and amount of data to send.
342 *
343 * The function queues data for sending. To actually send the buffered data,
344 * a work queue function is scheduled (with QUEUE_SNDBUF_DELAY).
345 * The function returns the number of data bytes that has been buffered.
346 *
347 * If the device is not connected, data is ignored and the function returns
348 * @count.
349 * If the buffer is full, the function returns 0.
350 * If an existing IUCV communicaton path has been severed, -EPIPE is returned
351 * (that can be passed to HVC layer to cause a tty hangup).
352 */
353static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf,
354 int count)
355{
356 size_t len;
357
358 if (priv->iucv_state == IUCV_DISCONN)
359 return count; /* ignore data */
360
361 if (priv->iucv_state == IUCV_SEVERED)
362 return -EPIPE;
363
364 len = min_t(size_t, count, SNDBUF_SIZE - priv->sndbuf_len);
365 if (!len)
366 return 0;
367
368 memcpy(priv->sndbuf + priv->sndbuf_len, buf, len);
369 priv->sndbuf_len += len;
370
371 if (priv->iucv_state == IUCV_CONNECTED)
372 schedule_delayed_work(&priv->sndbuf_work, QUEUE_SNDBUF_DELAY);
373
374 return len;
375}
376
377/**
378 * hvc_iucv_send() - Send an IUCV message containing terminal data.
379 * @priv: Pointer to struct hvc_iucv_private instance.
380 *
381 * If an IUCV communication path has been established, the buffered output data
382 * is sent via an IUCV message and the number of bytes sent is returned.
383 * Returns 0 if there is no established IUCV communication path or
384 * -EPIPE if an existing IUCV communicaton path has been severed.
385 */
386static int hvc_iucv_send(struct hvc_iucv_private *priv)
387{
388 struct iucv_tty_buffer *sb;
389 int rc, len;
390
391 if (priv->iucv_state == IUCV_SEVERED)
392 return -EPIPE;
393
394 if (priv->iucv_state == IUCV_DISCONN)
395 return -EIO;
396
397 if (!priv->sndbuf_len)
398 return 0;
399
400 /* allocate internal buffer to store msg data and also compute total
401 * message length */
402 sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC);
403 if (!sb)
404 return -ENOMEM;
405
406 memcpy(sb->mbuf->data, priv->sndbuf, priv->sndbuf_len);
407 sb->mbuf->datalen = (u16) priv->sndbuf_len;
408 sb->msg.length = MSG_SIZE(sb->mbuf->datalen);
409
410 list_add_tail(&sb->list, &priv->tty_outqueue);
411
412 rc = __iucv_message_send(priv->path, &sb->msg, 0, 0,
413 (void *) sb->mbuf, sb->msg.length);
414 if (rc) {
415 /* drop the message here; however we might want to handle
416 * 0x03 (msg limit reached) by trying again... */
417 list_del(&sb->list);
418 destroy_tty_buffer(sb);
419 }
420 len = priv->sndbuf_len;
421 priv->sndbuf_len = 0;
422
423 return len;
424}
425
426/**
427 * hvc_iucv_sndbuf_work() - Send buffered data over IUCV
428 * @work: Work structure.
429 *
430 * This work queue function sends buffered output data over IUCV and,
431 * if not all buffered data could be sent, reschedules itself.
432 */
433static void hvc_iucv_sndbuf_work(struct work_struct *work)
434{
435 struct hvc_iucv_private *priv;
436
437 priv = container_of(work, struct hvc_iucv_private, sndbuf_work.work);
438 if (!priv)
439 return;
440
441 spin_lock_bh(&priv->lock);
442 hvc_iucv_send(priv);
443 spin_unlock_bh(&priv->lock);
444}
445
446/**
447 * hvc_iucv_put_chars() - HVC put_chars operation.
448 * @vtermno: HVC virtual terminal number.
449 * @buf: Pointer to an buffer to read data from
450 * @count: Size of buffer available for reading
451 *
452 * The HVC thread calls this method to write characters to the back-end.
453 * The function calls hvc_iucv_queue() to queue terminal data for sending.
454 *
455 * Locking: The method gets called under an irqsave() spinlock; and
456 * locks struct hvc_iucv_private->lock.
457 */
458static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count)
459{
460 struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
461 int queued;
462
463 if (count <= 0)
464 return 0;
465
466 if (!priv)
467 return -ENODEV;
468
469 spin_lock(&priv->lock);
470 queued = hvc_iucv_queue(priv, buf, count);
471 spin_unlock(&priv->lock);
472
473 return queued;
474}
475
476/**
477 * hvc_iucv_notifier_add() - HVC notifier for opening a TTY for the first time.
478 * @hp: Pointer to the HVC device (struct hvc_struct)
479 * @id: Additional data (originally passed to hvc_alloc): the index of an struct
480 * hvc_iucv_private instance.
481 *
482 * The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private
483 * instance that is derived from @id. Always returns 0.
484 *
485 * Locking: struct hvc_iucv_private->lock, spin_lock_bh
486 */
487static int hvc_iucv_notifier_add(struct hvc_struct *hp, int id)
488{
489 struct hvc_iucv_private *priv;
490
491 priv = hvc_iucv_get_private(id);
492 if (!priv)
493 return 0;
494
495 spin_lock_bh(&priv->lock);
496 priv->tty_state = TTY_OPENED;
497 spin_unlock_bh(&priv->lock);
498
499 return 0;
500}
501
502/**
503 * hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance.
504 * @priv: Pointer to the struct hvc_iucv_private instance.
505 */
506static void hvc_iucv_cleanup(struct hvc_iucv_private *priv)
507{
508 destroy_tty_buffer_list(&priv->tty_outqueue);
509 destroy_tty_buffer_list(&priv->tty_inqueue);
510
511 priv->tty_state = TTY_CLOSED;
512 priv->iucv_state = IUCV_DISCONN;
513
514 priv->sndbuf_len = 0;
515}
516
517/**
518 * tty_outqueue_empty() - Test if the tty outq is empty
519 * @priv: Pointer to struct hvc_iucv_private instance.
520 */
521static inline int tty_outqueue_empty(struct hvc_iucv_private *priv)
522{
523 int rc;
524
525 spin_lock_bh(&priv->lock);
526 rc = list_empty(&priv->tty_outqueue);
527 spin_unlock_bh(&priv->lock);
528
529 return rc;
530}
531
532/**
533 * flush_sndbuf_sync() - Flush send buffer and wait for completion
534 * @priv: Pointer to struct hvc_iucv_private instance.
535 *
536 * The routine cancels a pending sndbuf work, calls hvc_iucv_send()
537 * to flush any buffered terminal output data and waits for completion.
538 */
539static void flush_sndbuf_sync(struct hvc_iucv_private *priv)
540{
541 int sync_wait;
542
543 cancel_delayed_work_sync(&priv->sndbuf_work);
544
545 spin_lock_bh(&priv->lock);
546 hvc_iucv_send(priv); /* force sending buffered data */
547 sync_wait = !list_empty(&priv->tty_outqueue); /* anything queued ? */
548 spin_unlock_bh(&priv->lock);
549
550 if (sync_wait)
551 wait_event_timeout(priv->sndbuf_waitq,
552 tty_outqueue_empty(priv), HZ/10);
553}
554
555/**
556 * hvc_iucv_hangup() - Sever IUCV path and schedule hvc tty hang up
557 * @priv: Pointer to hvc_iucv_private structure
558 *
559 * This routine severs an existing IUCV communication path and hangs
560 * up the underlying HVC terminal device.
561 * The hang-up occurs only if an IUCV communication path is established;
562 * otherwise there is no need to hang up the terminal device.
563 *
564 * The IUCV HVC hang-up is separated into two steps:
565 * 1. After the IUCV path has been severed, the iucv_state is set to
566 * IUCV_SEVERED.
567 * 2. Later, when the HVC thread calls hvc_iucv_get_chars(), the
568 * IUCV_SEVERED state causes the tty hang-up in the HVC layer.
569 *
570 * If the tty has not yet been opened, clean up the hvc_iucv_private
571 * structure to allow re-connects.
572 * If the tty has been opened, let get_chars() return -EPIPE to signal
573 * the HVC layer to hang up the tty and, if so, wake up the HVC thread
574 * to call get_chars()...
575 *
576 * Special notes on hanging up a HVC terminal instantiated as console:
577 * Hang-up: 1. do_tty_hangup() replaces file ops (= hung_up_tty_fops)
578 * 2. do_tty_hangup() calls tty->ops->close() for console_filp
579 * => no hangup notifier is called by HVC (default)
580 * 2. hvc_close() returns because of tty_hung_up_p(filp)
581 * => no delete notifier is called!
582 * Finally, the back-end is not being notified, thus, the tty session is
583 * kept active (TTY_OPEN) to be ready for re-connects.
584 *
585 * Locking: spin_lock(&priv->lock) w/o disabling bh
586 */
587static void hvc_iucv_hangup(struct hvc_iucv_private *priv)
588{
589 struct iucv_path *path;
590
591 path = NULL;
592 spin_lock(&priv->lock);
593 if (priv->iucv_state == IUCV_CONNECTED) {
594 path = priv->path;
595 priv->path = NULL;
596 priv->iucv_state = IUCV_SEVERED;
597 if (priv->tty_state == TTY_CLOSED)
598 hvc_iucv_cleanup(priv);
599 else
600 /* console is special (see above) */
601 if (priv->is_console) {
602 hvc_iucv_cleanup(priv);
603 priv->tty_state = TTY_OPENED;
604 } else
605 hvc_kick();
606 }
607 spin_unlock(&priv->lock);
608
609 /* finally sever path (outside of priv->lock due to lock ordering) */
610 if (path) {
611 iucv_path_sever(path, NULL);
612 iucv_path_free(path);
613 }
614}
615
616/**
617 * hvc_iucv_notifier_hangup() - HVC notifier for TTY hangups.
618 * @hp: Pointer to the HVC device (struct hvc_struct)
619 * @id: Additional data (originally passed to hvc_alloc):
620 * the index of an struct hvc_iucv_private instance.
621 *
622 * This routine notifies the HVC back-end that a tty hangup (carrier loss,
623 * virtual or otherwise) has occured.
624 * The z/VM IUCV HVC device driver ignores virtual hangups (vhangup())
625 * to keep an existing IUCV communication path established.
626 * (Background: vhangup() is called from user space (by getty or login) to
627 * disable writing to the tty by other applications).
628 * If the tty has been opened and an established IUCV path has been severed
629 * (we caused the tty hangup), the function calls hvc_iucv_cleanup().
630 *
631 * Locking: struct hvc_iucv_private->lock
632 */
633static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id)
634{
635 struct hvc_iucv_private *priv;
636
637 priv = hvc_iucv_get_private(id);
638 if (!priv)
639 return;
640
641 flush_sndbuf_sync(priv);
642
643 spin_lock_bh(&priv->lock);
644 /* NOTE: If the hangup was scheduled by ourself (from the iucv
645 * path_servered callback [IUCV_SEVERED]), we have to clean up
646 * our structure and to set state to TTY_CLOSED.
647 * If the tty was hung up otherwise (e.g. vhangup()), then we
648 * ignore this hangup and keep an established IUCV path open...
649 * (...the reason is that we are not able to connect back to the
650 * client if we disconnect on hang up) */
651 priv->tty_state = TTY_CLOSED;
652
653 if (priv->iucv_state == IUCV_SEVERED)
654 hvc_iucv_cleanup(priv);
655 spin_unlock_bh(&priv->lock);
656}
657
658/**
659 * hvc_iucv_notifier_del() - HVC notifier for closing a TTY for the last time.
660 * @hp: Pointer to the HVC device (struct hvc_struct)
661 * @id: Additional data (originally passed to hvc_alloc):
662 * the index of an struct hvc_iucv_private instance.
663 *
664 * This routine notifies the HVC back-end that the last tty device fd has been
665 * closed. The function calls hvc_iucv_cleanup() to clean up the struct
666 * hvc_iucv_private instance.
667 *
668 * Locking: struct hvc_iucv_private->lock
669 */
670static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id)
671{
672 struct hvc_iucv_private *priv;
673 struct iucv_path *path;
674
675 priv = hvc_iucv_get_private(id);
676 if (!priv)
677 return;
678
679 flush_sndbuf_sync(priv);
680
681 spin_lock_bh(&priv->lock);
682 path = priv->path; /* save reference to IUCV path */
683 priv->path = NULL;
684 hvc_iucv_cleanup(priv);
685 spin_unlock_bh(&priv->lock);
686
687 /* sever IUCV path outside of priv->lock due to lock ordering of:
688 * priv->lock <--> iucv_table_lock */
689 if (path) {
690 iucv_path_sever(path, NULL);
691 iucv_path_free(path);
692 }
693}
694
695/**
696 * hvc_iucv_filter_connreq() - Filter connection request based on z/VM user ID
697 * @ipvmid: Originating z/VM user ID (right padded with blanks)
698 *
699 * Returns 0 if the z/VM user ID @ipvmid is allowed to connection, otherwise
700 * non-zero.
701 */
702static int hvc_iucv_filter_connreq(u8 ipvmid[8])
703{
704 size_t i;
705
706 /* Note: default policy is ACCEPT if no filter is set */
707 if (!hvc_iucv_filter_size)
708 return 0;
709
710 for (i = 0; i < hvc_iucv_filter_size; i++)
711 if (0 == memcmp(ipvmid, hvc_iucv_filter + (8 * i), 8))
712 return 0;
713 return 1;
714}
715
716/**
717 * hvc_iucv_path_pending() - IUCV handler to process a connection request.
718 * @path: Pending path (struct iucv_path)
719 * @ipvmid: z/VM system identifier of originator
720 * @ipuser: User specified data for this path
721 * (AF_IUCV: port/service name and originator port)
722 *
723 * The function uses the @ipuser data to determine if the pending path belongs
724 * to a terminal managed by this device driver.
725 * If the path belongs to this driver, ensure that the terminal is not accessed
726 * multiple times (only one connection to a terminal is allowed).
727 * If the terminal is not yet connected, the pending path is accepted and is
728 * associated to the appropriate struct hvc_iucv_private instance.
729 *
730 * Returns 0 if @path belongs to a terminal managed by the this device driver;
731 * otherwise returns -ENODEV in order to dispatch this path to other handlers.
732 *
733 * Locking: struct hvc_iucv_private->lock
734 */
735static int hvc_iucv_path_pending(struct iucv_path *path,
736 u8 ipvmid[8], u8 ipuser[16])
737{
738 struct hvc_iucv_private *priv;
739 u8 nuser_data[16];
740 u8 vm_user_id[9];
741 int i, rc;
742
743 priv = NULL;
744 for (i = 0; i < hvc_iucv_devices; i++)
745 if (hvc_iucv_table[i] &&
746 (0 == memcmp(hvc_iucv_table[i]->srv_name, ipuser, 8))) {
747 priv = hvc_iucv_table[i];
748 break;
749 }
750 if (!priv)
751 return -ENODEV;
752
753 /* Enforce that ipvmid is allowed to connect to us */
754 read_lock(&hvc_iucv_filter_lock);
755 rc = hvc_iucv_filter_connreq(ipvmid);
756 read_unlock(&hvc_iucv_filter_lock);
757 if (rc) {
758 iucv_path_sever(path, ipuser);
759 iucv_path_free(path);
760 memcpy(vm_user_id, ipvmid, 8);
761 vm_user_id[8] = 0;
762 pr_info("A connection request from z/VM user ID %s "
763 "was refused\n", vm_user_id);
764 return 0;
765 }
766
767 spin_lock(&priv->lock);
768
769 /* If the terminal is already connected or being severed, then sever
770 * this path to enforce that there is only ONE established communication
771 * path per terminal. */
772 if (priv->iucv_state != IUCV_DISCONN) {
773 iucv_path_sever(path, ipuser);
774 iucv_path_free(path);
775 goto out_path_handled;
776 }
777
778 /* accept path */
779 memcpy(nuser_data, ipuser + 8, 8); /* remote service (for af_iucv) */
780 memcpy(nuser_data + 8, ipuser, 8); /* local service (for af_iucv) */
781 path->msglim = 0xffff; /* IUCV MSGLIMIT */
782 path->flags &= ~IUCV_IPRMDATA; /* TODO: use IUCV_IPRMDATA */
783 rc = iucv_path_accept(path, &hvc_iucv_handler, nuser_data, priv);
784 if (rc) {
785 iucv_path_sever(path, ipuser);
786 iucv_path_free(path);
787 goto out_path_handled;
788 }
789 priv->path = path;
790 priv->iucv_state = IUCV_CONNECTED;
791
792 /* flush buffered output data... */
793 schedule_delayed_work(&priv->sndbuf_work, 5);
794
795out_path_handled:
796 spin_unlock(&priv->lock);
797 return 0;
798}
799
800/**
801 * hvc_iucv_path_severed() - IUCV handler to process a path sever.
802 * @path: Pending path (struct iucv_path)
803 * @ipuser: User specified data for this path
804 * (AF_IUCV: port/service name and originator port)
805 *
806 * This function calls the hvc_iucv_hangup() function for the
807 * respective IUCV HVC terminal.
808 *
809 * Locking: struct hvc_iucv_private->lock
810 */
811static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16])
812{
813 struct hvc_iucv_private *priv = path->private;
814
815 hvc_iucv_hangup(priv);
816}
817
818/**
819 * hvc_iucv_msg_pending() - IUCV handler to process an incoming IUCV message.
820 * @path: Pending path (struct iucv_path)
821 * @msg: Pointer to the IUCV message
822 *
823 * The function puts an incoming message on the input queue for later
824 * processing (by hvc_iucv_get_chars() / hvc_iucv_write()).
825 * If the tty has not yet been opened, the message is rejected.
826 *
827 * Locking: struct hvc_iucv_private->lock
828 */
829static void hvc_iucv_msg_pending(struct iucv_path *path,
830 struct iucv_message *msg)
831{
832 struct hvc_iucv_private *priv = path->private;
833 struct iucv_tty_buffer *rb;
834
835 /* reject messages that exceed max size of iucv_tty_msg->datalen */
836 if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) {
837 iucv_message_reject(path, msg);
838 return;
839 }
840
841 spin_lock(&priv->lock);
842
843 /* reject messages if tty has not yet been opened */
844 if (priv->tty_state == TTY_CLOSED) {
845 iucv_message_reject(path, msg);
846 goto unlock_return;
847 }
848
849 /* allocate tty buffer to save iucv msg only */
850 rb = alloc_tty_buffer(0, GFP_ATOMIC);
851 if (!rb) {
852 iucv_message_reject(path, msg);
853 goto unlock_return; /* -ENOMEM */
854 }
855 rb->msg = *msg;
856
857 list_add_tail(&rb->list, &priv->tty_inqueue);
858
859 hvc_kick(); /* wake up hvc thread */
860
861unlock_return:
862 spin_unlock(&priv->lock);
863}
864
865/**
866 * hvc_iucv_msg_complete() - IUCV handler to process message completion
867 * @path: Pending path (struct iucv_path)
868 * @msg: Pointer to the IUCV message
869 *
870 * The function is called upon completion of message delivery to remove the
871 * message from the outqueue. Additional delivery information can be found
872 * msg->audit: rejected messages (0x040000 (IPADRJCT)), and
873 * purged messages (0x010000 (IPADPGNR)).
874 *
875 * Locking: struct hvc_iucv_private->lock
876 */
877static void hvc_iucv_msg_complete(struct iucv_path *path,
878 struct iucv_message *msg)
879{
880 struct hvc_iucv_private *priv = path->private;
881 struct iucv_tty_buffer *ent, *next;
882 LIST_HEAD(list_remove);
883
884 spin_lock(&priv->lock);
885 list_for_each_entry_safe(ent, next, &priv->tty_outqueue, list)
886 if (ent->msg.id == msg->id) {
887 list_move(&ent->list, &list_remove);
888 break;
889 }
890 wake_up(&priv->sndbuf_waitq);
891 spin_unlock(&priv->lock);
892 destroy_tty_buffer_list(&list_remove);
893}
894
895/**
896 * hvc_iucv_pm_freeze() - Freeze PM callback
897 * @dev: IUVC HVC terminal device
898 *
899 * Sever an established IUCV communication path and
900 * trigger a hang-up of the underlying HVC terminal.
901 */
902static int hvc_iucv_pm_freeze(struct device *dev)
903{
904 struct hvc_iucv_private *priv = dev_get_drvdata(dev);
905
906 local_bh_disable();
907 hvc_iucv_hangup(priv);
908 local_bh_enable();
909
910 return 0;
911}
912
913/**
914 * hvc_iucv_pm_restore_thaw() - Thaw and restore PM callback
915 * @dev: IUVC HVC terminal device
916 *
917 * Wake up the HVC thread to trigger hang-up and respective
918 * HVC back-end notifier invocations.
919 */
920static int hvc_iucv_pm_restore_thaw(struct device *dev)
921{
922 hvc_kick();
923 return 0;
924}
925
926
927/* HVC operations */
928static const struct hv_ops hvc_iucv_ops = {
929 .get_chars = hvc_iucv_get_chars,
930 .put_chars = hvc_iucv_put_chars,
931 .notifier_add = hvc_iucv_notifier_add,
932 .notifier_del = hvc_iucv_notifier_del,
933 .notifier_hangup = hvc_iucv_notifier_hangup,
934};
935
936/* Suspend / resume device operations */
937static const struct dev_pm_ops hvc_iucv_pm_ops = {
938 .freeze = hvc_iucv_pm_freeze,
939 .thaw = hvc_iucv_pm_restore_thaw,
940 .restore = hvc_iucv_pm_restore_thaw,
941};
942
943/* IUCV HVC device driver */
944static struct device_driver hvc_iucv_driver = {
945 .name = KMSG_COMPONENT,
946 .bus = &iucv_bus,
947 .pm = &hvc_iucv_pm_ops,
948};
949
950/**
951 * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance
952 * @id: hvc_iucv_table index
953 * @is_console: Flag if the instance is used as Linux console
954 *
955 * This function allocates a new hvc_iucv_private structure and stores
956 * the instance in hvc_iucv_table at index @id.
957 * Returns 0 on success; otherwise non-zero.
958 */
959static int __init hvc_iucv_alloc(int id, unsigned int is_console)
960{
961 struct hvc_iucv_private *priv;
962 char name[9];
963 int rc;
964
965 priv = kzalloc(sizeof(struct hvc_iucv_private), GFP_KERNEL);
966 if (!priv)
967 return -ENOMEM;
968
969 spin_lock_init(&priv->lock);
970 INIT_LIST_HEAD(&priv->tty_outqueue);
971 INIT_LIST_HEAD(&priv->tty_inqueue);
972 INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work);
973 init_waitqueue_head(&priv->sndbuf_waitq);
974
975 priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL);
976 if (!priv->sndbuf) {
977 kfree(priv);
978 return -ENOMEM;
979 }
980
981 /* set console flag */
982 priv->is_console = is_console;
983
984 /* allocate hvc device */
985 priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /* PAGE_SIZE */
986 HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256);
987 if (IS_ERR(priv->hvc)) {
988 rc = PTR_ERR(priv->hvc);
989 goto out_error_hvc;
990 }
991
992 /* notify HVC thread instead of using polling */
993 priv->hvc->irq_requested = 1;
994
995 /* setup iucv related information */
996 snprintf(name, 9, "lnxhvc%-2d", id);
997 memcpy(priv->srv_name, name, 8);
998 ASCEBC(priv->srv_name, 8);
999
1000 /* create and setup device */
1001 priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL);
1002 if (!priv->dev) {
1003 rc = -ENOMEM;
1004 goto out_error_dev;
1005 }
1006 dev_set_name(priv->dev, "hvc_iucv%d", id);
1007 dev_set_drvdata(priv->dev, priv);
1008 priv->dev->bus = &iucv_bus;
1009 priv->dev->parent = iucv_root;
1010 priv->dev->driver = &hvc_iucv_driver;
1011 priv->dev->release = (void (*)(struct device *)) kfree;
1012 rc = device_register(priv->dev);
1013 if (rc) {
1014 put_device(priv->dev);
1015 goto out_error_dev;
1016 }
1017
1018 hvc_iucv_table[id] = priv;
1019 return 0;
1020
1021out_error_dev:
1022 hvc_remove(priv->hvc);
1023out_error_hvc:
1024 free_page((unsigned long) priv->sndbuf);
1025 kfree(priv);
1026
1027 return rc;
1028}
1029
1030/**
1031 * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances
1032 */
1033static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv)
1034{
1035 hvc_remove(priv->hvc);
1036 device_unregister(priv->dev);
1037 free_page((unsigned long) priv->sndbuf);
1038 kfree(priv);
1039}
1040
1041/**
1042 * hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID
1043 * @filter: String containing a comma-separated list of z/VM user IDs
1044 */
1045static const char *hvc_iucv_parse_filter(const char *filter, char *dest)
1046{
1047 const char *nextdelim, *residual;
1048 size_t len;
1049
1050 nextdelim = strchr(filter, ',');
1051 if (nextdelim) {
1052 len = nextdelim - filter;
1053 residual = nextdelim + 1;
1054 } else {
1055 len = strlen(filter);
1056 residual = filter + len;
1057 }
1058
1059 if (len == 0)
1060 return ERR_PTR(-EINVAL);
1061
1062 /* check for '\n' (if called from sysfs) */
1063 if (filter[len - 1] == '\n')
1064 len--;
1065
1066 if (len > 8)
1067 return ERR_PTR(-EINVAL);
1068
1069 /* pad with blanks and save upper case version of user ID */
1070 memset(dest, ' ', 8);
1071 while (len--)
1072 dest[len] = toupper(filter[len]);
1073 return residual;
1074}
1075
1076/**
1077 * hvc_iucv_setup_filter() - Set up z/VM user ID filter
1078 * @filter: String consisting of a comma-separated list of z/VM user IDs
1079 *
1080 * The function parses the @filter string and creates an array containing
1081 * the list of z/VM user ID filter entries.
1082 * Return code 0 means success, -EINVAL if the filter is syntactically
1083 * incorrect, -ENOMEM if there was not enough memory to allocate the
1084 * filter list array, or -ENOSPC if too many z/VM user IDs have been specified.
1085 */
1086static int hvc_iucv_setup_filter(const char *val)
1087{
1088 const char *residual;
1089 int err;
1090 size_t size, count;
1091 void *array, *old_filter;
1092
1093 count = strlen(val);
1094 if (count == 0 || (count == 1 && val[0] == '\n')) {
1095 size = 0;
1096 array = NULL;
1097 goto out_replace_filter; /* clear filter */
1098 }
1099
1100 /* count user IDs in order to allocate sufficient memory */
1101 size = 1;
1102 residual = val;
1103 while ((residual = strchr(residual, ',')) != NULL) {
1104 residual++;
1105 size++;
1106 }
1107
1108 /* check if the specified list exceeds the filter limit */
1109 if (size > MAX_VMID_FILTER)
1110 return -ENOSPC;
1111
1112 array = kzalloc(size * 8, GFP_KERNEL);
1113 if (!array)
1114 return -ENOMEM;
1115
1116 count = size;
1117 residual = val;
1118 while (*residual && count) {
1119 residual = hvc_iucv_parse_filter(residual,
1120 array + ((size - count) * 8));
1121 if (IS_ERR(residual)) {
1122 err = PTR_ERR(residual);
1123 kfree(array);
1124 goto out_err;
1125 }
1126 count--;
1127 }
1128
1129out_replace_filter:
1130 write_lock_bh(&hvc_iucv_filter_lock);
1131 old_filter = hvc_iucv_filter;
1132 hvc_iucv_filter_size = size;
1133 hvc_iucv_filter = array;
1134 write_unlock_bh(&hvc_iucv_filter_lock);
1135 kfree(old_filter);
1136
1137 err = 0;
1138out_err:
1139 return err;
1140}
1141
1142/**
1143 * param_set_vmidfilter() - Set z/VM user ID filter parameter
1144 * @val: String consisting of a comma-separated list of z/VM user IDs
1145 * @kp: Kernel parameter pointing to hvc_iucv_filter array
1146 *
1147 * The function sets up the z/VM user ID filter specified as comma-separated
1148 * list of user IDs in @val.
1149 * Note: If it is called early in the boot process, @val is stored and
1150 * parsed later in hvc_iucv_init().
1151 */
1152static int param_set_vmidfilter(const char *val, const struct kernel_param *kp)
1153{
1154 int rc;
1155
1156 if (!MACHINE_IS_VM || !hvc_iucv_devices)
1157 return -ENODEV;
1158
1159 if (!val)
1160 return -EINVAL;
1161
1162 rc = 0;
1163 if (slab_is_available())
1164 rc = hvc_iucv_setup_filter(val);
1165 else
1166 hvc_iucv_filter_string = val; /* defer... */
1167 return rc;
1168}
1169
1170/**
1171 * param_get_vmidfilter() - Get z/VM user ID filter
1172 * @buffer: Buffer to store z/VM user ID filter,
1173 * (buffer size assumption PAGE_SIZE)
1174 * @kp: Kernel parameter pointing to the hvc_iucv_filter array
1175 *
1176 * The function stores the filter as a comma-separated list of z/VM user IDs
1177 * in @buffer. Typically, sysfs routines call this function for attr show.
1178 */
1179static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp)
1180{
1181 int rc;
1182 size_t index, len;
1183 void *start, *end;
1184
1185 if (!MACHINE_IS_VM || !hvc_iucv_devices)
1186 return -ENODEV;
1187
1188 rc = 0;
1189 read_lock_bh(&hvc_iucv_filter_lock);
1190 for (index = 0; index < hvc_iucv_filter_size; index++) {
1191 start = hvc_iucv_filter + (8 * index);
1192 end = memchr(start, ' ', 8);
1193 len = (end) ? end - start : 8;
1194 memcpy(buffer + rc, start, len);
1195 rc += len;
1196 buffer[rc++] = ',';
1197 }
1198 read_unlock_bh(&hvc_iucv_filter_lock);
1199 if (rc)
1200 buffer[--rc] = '\0'; /* replace last comma and update rc */
1201 return rc;
1202}
1203
1204#define param_check_vmidfilter(name, p) __param_check(name, p, void)
1205
1206static struct kernel_param_ops param_ops_vmidfilter = {
1207 .set = param_set_vmidfilter,
1208 .get = param_get_vmidfilter,
1209};
1210
1211/**
1212 * hvc_iucv_init() - z/VM IUCV HVC device driver initialization
1213 */
1214static int __init hvc_iucv_init(void)
1215{
1216 int rc;
1217 unsigned int i;
1218
1219 if (!hvc_iucv_devices)
1220 return -ENODEV;
1221
1222 if (!MACHINE_IS_VM) {
1223 pr_notice("The z/VM IUCV HVC device driver cannot "
1224 "be used without z/VM\n");
1225 rc = -ENODEV;
1226 goto out_error;
1227 }
1228
1229 if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) {
1230 pr_err("%lu is not a valid value for the hvc_iucv= "
1231 "kernel parameter\n", hvc_iucv_devices);
1232 rc = -EINVAL;
1233 goto out_error;
1234 }
1235
1236 /* register IUCV HVC device driver */
1237 rc = driver_register(&hvc_iucv_driver);
1238 if (rc)
1239 goto out_error;
1240
1241 /* parse hvc_iucv_allow string and create z/VM user ID filter list */
1242 if (hvc_iucv_filter_string) {
1243 rc = hvc_iucv_setup_filter(hvc_iucv_filter_string);
1244 switch (rc) {
1245 case 0:
1246 break;
1247 case -ENOMEM:
1248 pr_err("Allocating memory failed with "
1249 "reason code=%d\n", 3);
1250 goto out_error;
1251 case -EINVAL:
1252 pr_err("hvc_iucv_allow= does not specify a valid "
1253 "z/VM user ID list\n");
1254 goto out_error;
1255 case -ENOSPC:
1256 pr_err("hvc_iucv_allow= specifies too many "
1257 "z/VM user IDs\n");
1258 goto out_error;
1259 default:
1260 goto out_error;
1261 }
1262 }
1263
1264 hvc_iucv_buffer_cache = kmem_cache_create(KMSG_COMPONENT,
1265 sizeof(struct iucv_tty_buffer),
1266 0, 0, NULL);
1267 if (!hvc_iucv_buffer_cache) {
1268 pr_err("Allocating memory failed with reason code=%d\n", 1);
1269 rc = -ENOMEM;
1270 goto out_error;
1271 }
1272
1273 hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR,
1274 hvc_iucv_buffer_cache);
1275 if (!hvc_iucv_mempool) {
1276 pr_err("Allocating memory failed with reason code=%d\n", 2);
1277 kmem_cache_destroy(hvc_iucv_buffer_cache);
1278 rc = -ENOMEM;
1279 goto out_error;
1280 }
1281
1282 /* register the first terminal device as console
1283 * (must be done before allocating hvc terminal devices) */
1284 rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops);
1285 if (rc) {
1286 pr_err("Registering HVC terminal device as "
1287 "Linux console failed\n");
1288 goto out_error_memory;
1289 }
1290
1291 /* allocate hvc_iucv_private structs */
1292 for (i = 0; i < hvc_iucv_devices; i++) {
1293 rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0);
1294 if (rc) {
1295 pr_err("Creating a new HVC terminal device "
1296 "failed with error code=%d\n", rc);
1297 goto out_error_hvc;
1298 }
1299 }
1300
1301 /* register IUCV callback handler */
1302 rc = iucv_register(&hvc_iucv_handler, 0);
1303 if (rc) {
1304 pr_err("Registering IUCV handlers failed with error code=%d\n",
1305 rc);
1306 goto out_error_hvc;
1307 }
1308
1309 return 0;
1310
1311out_error_hvc:
1312 for (i = 0; i < hvc_iucv_devices; i++)
1313 if (hvc_iucv_table[i])
1314 hvc_iucv_destroy(hvc_iucv_table[i]);
1315out_error_memory:
1316 mempool_destroy(hvc_iucv_mempool);
1317 kmem_cache_destroy(hvc_iucv_buffer_cache);
1318out_error:
1319 if (hvc_iucv_filter)
1320 kfree(hvc_iucv_filter);
1321 hvc_iucv_devices = 0; /* ensure that we do not provide any device */
1322 return rc;
1323}
1324
1325/**
1326 * hvc_iucv_config() - Parsing of hvc_iucv= kernel command line parameter
1327 * @val: Parameter value (numeric)
1328 */
1329static int __init hvc_iucv_config(char *val)
1330{
1331 return strict_strtoul(val, 10, &hvc_iucv_devices);
1332}
1333
1334
1335device_initcall(hvc_iucv_init);
1336__setup("hvc_iucv=", hvc_iucv_config);
1337core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640);
diff --git a/drivers/tty/hvc/hvc_rtas.c b/drivers/tty/hvc/hvc_rtas.c
new file mode 100644
index 000000000000..61c4a61558d9
--- /dev/null
+++ b/drivers/tty/hvc/hvc_rtas.c
@@ -0,0 +1,133 @@
1/*
2 * IBM RTAS driver interface to hvc_console.c
3 *
4 * (C) Copyright IBM Corporation 2001-2005
5 * (C) Copyright Red Hat, Inc. 2005
6 *
7 * Author(s): Maximino Augilar <IBM STI Design Center>
8 * : Ryan S. Arnold <rsa@us.ibm.com>
9 * : Utz Bacher <utz.bacher@de.ibm.com>
10 * : David Woodhouse <dwmw2@infradead.org>
11 *
12 * inspired by drivers/char/hvc_console.c
13 * written by Anton Blanchard and Paul Mackerras
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
19 *
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28 */
29
30#include <linux/console.h>
31#include <linux/delay.h>
32#include <linux/err.h>
33#include <linux/init.h>
34#include <linux/moduleparam.h>
35#include <linux/types.h>
36
37#include <asm/irq.h>
38#include <asm/rtas.h>
39#include "hvc_console.h"
40
41#define hvc_rtas_cookie 0x67781e15
42struct hvc_struct *hvc_rtas_dev;
43
44static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
45static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
46
47static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
48 int count)
49{
50 int i;
51
52 for (i = 0; i < count; i++) {
53 if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
54 break;
55 }
56
57 return i;
58}
59
60static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
61{
62 int i, c;
63
64 for (i = 0; i < count; i++) {
65 if (rtas_call(rtascons_get_char_token, 0, 2, &c))
66 break;
67
68 buf[i] = c;
69 }
70
71 return i;
72}
73
74static const struct hv_ops hvc_rtas_get_put_ops = {
75 .get_chars = hvc_rtas_read_console,
76 .put_chars = hvc_rtas_write_console,
77};
78
79static int __init hvc_rtas_init(void)
80{
81 struct hvc_struct *hp;
82
83 if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
84 rtascons_put_char_token = rtas_token("put-term-char");
85 if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
86 return -EIO;
87
88 if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
89 rtascons_get_char_token = rtas_token("get-term-char");
90 if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
91 return -EIO;
92
93 BUG_ON(hvc_rtas_dev);
94
95 /* Allocate an hvc_struct for the console device we instantiated
96 * earlier. Save off hp so that we can return it on exit */
97 hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops, 16);
98 if (IS_ERR(hp))
99 return PTR_ERR(hp);
100
101 hvc_rtas_dev = hp;
102
103 return 0;
104}
105module_init(hvc_rtas_init);
106
107/* This will tear down the tty portion of the driver */
108static void __exit hvc_rtas_exit(void)
109{
110 /* Really the fun isn't over until the worker thread breaks down and
111 * the tty cleans up */
112 if (hvc_rtas_dev)
113 hvc_remove(hvc_rtas_dev);
114}
115module_exit(hvc_rtas_exit);
116
117/* This will happen prior to module init. There is no tty at this time? */
118static int __init hvc_rtas_console_init(void)
119{
120 rtascons_put_char_token = rtas_token("put-term-char");
121 if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
122 return -EIO;
123
124 rtascons_get_char_token = rtas_token("get-term-char");
125 if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
126 return -EIO;
127
128 hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops);
129 add_preferred_console("hvc", 0, NULL);
130
131 return 0;
132}
133console_initcall(hvc_rtas_console_init);
diff --git a/drivers/tty/hvc/hvc_tile.c b/drivers/tty/hvc/hvc_tile.c
new file mode 100644
index 000000000000..7a84a0595477
--- /dev/null
+++ b/drivers/tty/hvc/hvc_tile.c
@@ -0,0 +1,68 @@
1/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 *
14 * Tilera TILE Processor hypervisor console
15 */
16
17#include <linux/console.h>
18#include <linux/delay.h>
19#include <linux/err.h>
20#include <linux/init.h>
21#include <linux/moduleparam.h>
22#include <linux/types.h>
23
24#include <hv/hypervisor.h>
25
26#include "hvc_console.h"
27
28static int hvc_tile_put_chars(uint32_t vt, const char *buf, int count)
29{
30 return hv_console_write((HV_VirtAddr)buf, count);
31}
32
33static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
34{
35 int i, c;
36
37 for (i = 0; i < count; ++i) {
38 c = hv_console_read_if_ready();
39 if (c < 0)
40 break;
41 buf[i] = c;
42 }
43
44 return i;
45}
46
47static const struct hv_ops hvc_tile_get_put_ops = {
48 .get_chars = hvc_tile_get_chars,
49 .put_chars = hvc_tile_put_chars,
50};
51
52static int __init hvc_tile_console_init(void)
53{
54 extern void disable_early_printk(void);
55 hvc_instantiate(0, 0, &hvc_tile_get_put_ops);
56 add_preferred_console("hvc", 0, NULL);
57 disable_early_printk();
58 return 0;
59}
60console_initcall(hvc_tile_console_init);
61
62static int __init hvc_tile_init(void)
63{
64 struct hvc_struct *s;
65 s = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
66 return IS_ERR(s) ? PTR_ERR(s) : 0;
67}
68device_initcall(hvc_tile_init);
diff --git a/drivers/tty/hvc/hvc_udbg.c b/drivers/tty/hvc/hvc_udbg.c
new file mode 100644
index 000000000000..b0957e61a7be
--- /dev/null
+++ b/drivers/tty/hvc/hvc_udbg.c
@@ -0,0 +1,96 @@
1/*
2 * udbg interface to hvc_console.c
3 *
4 * (C) Copyright David Gibson, IBM Corporation 2008.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/console.h>
22#include <linux/delay.h>
23#include <linux/err.h>
24#include <linux/init.h>
25#include <linux/moduleparam.h>
26#include <linux/types.h>
27#include <linux/irq.h>
28
29#include <asm/udbg.h>
30
31#include "hvc_console.h"
32
33struct hvc_struct *hvc_udbg_dev;
34
35static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
36{
37 int i;
38
39 for (i = 0; i < count; i++)
40 udbg_putc(buf[i]);
41
42 return i;
43}
44
45static int hvc_udbg_get(uint32_t vtermno, char *buf, int count)
46{
47 int i, c;
48
49 if (!udbg_getc_poll)
50 return 0;
51
52 for (i = 0; i < count; i++) {
53 if ((c = udbg_getc_poll()) == -1)
54 break;
55 buf[i] = c;
56 }
57
58 return i;
59}
60
61static const struct hv_ops hvc_udbg_ops = {
62 .get_chars = hvc_udbg_get,
63 .put_chars = hvc_udbg_put,
64};
65
66static int __init hvc_udbg_init(void)
67{
68 struct hvc_struct *hp;
69
70 BUG_ON(hvc_udbg_dev);
71
72 hp = hvc_alloc(0, NO_IRQ, &hvc_udbg_ops, 16);
73 if (IS_ERR(hp))
74 return PTR_ERR(hp);
75
76 hvc_udbg_dev = hp;
77
78 return 0;
79}
80module_init(hvc_udbg_init);
81
82static void __exit hvc_udbg_exit(void)
83{
84 if (hvc_udbg_dev)
85 hvc_remove(hvc_udbg_dev);
86}
87module_exit(hvc_udbg_exit);
88
89static int __init hvc_udbg_console_init(void)
90{
91 hvc_instantiate(0, 0, &hvc_udbg_ops);
92 add_preferred_console("hvc", 0, NULL);
93
94 return 0;
95}
96console_initcall(hvc_udbg_console_init);
diff --git a/drivers/tty/hvc/hvc_vio.c b/drivers/tty/hvc/hvc_vio.c
new file mode 100644
index 000000000000..5e2f52b33327
--- /dev/null
+++ b/drivers/tty/hvc/hvc_vio.c
@@ -0,0 +1,173 @@
1/*
2 * vio driver interface to hvc_console.c
3 *
4 * This code was moved here to allow the remaing code to be reused as a
5 * generic polling mode with semi-reliable transport driver core to the
6 * console and tty subsystems.
7 *
8 *
9 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
10 * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
11 * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
12 * Copyright (C) 2004 IBM Corporation
13 *
14 * Additional Author(s):
15 * Ryan S. Arnold <rsa@us.ibm.com>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 */
31
32#include <linux/types.h>
33#include <linux/init.h>
34
35#include <asm/hvconsole.h>
36#include <asm/vio.h>
37#include <asm/prom.h>
38#include <asm/firmware.h>
39
40#include "hvc_console.h"
41
42static const char hvc_driver_name[] = "hvc_console";
43
44static struct vio_device_id hvc_driver_table[] __devinitdata = {
45 {"serial", "hvterm1"},
46 { "", "" }
47};
48MODULE_DEVICE_TABLE(vio, hvc_driver_table);
49
50static int filtered_get_chars(uint32_t vtermno, char *buf, int count)
51{
52 unsigned long got;
53 int i;
54
55 /*
56 * Vio firmware will read up to SIZE_VIO_GET_CHARS at its own discretion
57 * so we play safe and avoid the situation where got > count which could
58 * overload the flip buffer.
59 */
60 if (count < SIZE_VIO_GET_CHARS)
61 return -EAGAIN;
62
63 got = hvc_get_chars(vtermno, buf, count);
64
65 /*
66 * Work around a HV bug where it gives us a null
67 * after every \r. -- paulus
68 */
69 for (i = 1; i < got; ++i) {
70 if (buf[i] == 0 && buf[i-1] == '\r') {
71 --got;
72 if (i < got)
73 memmove(&buf[i], &buf[i+1],
74 got - i);
75 }
76 }
77 return got;
78}
79
80static const struct hv_ops hvc_get_put_ops = {
81 .get_chars = filtered_get_chars,
82 .put_chars = hvc_put_chars,
83 .notifier_add = notifier_add_irq,
84 .notifier_del = notifier_del_irq,
85 .notifier_hangup = notifier_hangup_irq,
86};
87
88static int __devinit hvc_vio_probe(struct vio_dev *vdev,
89 const struct vio_device_id *id)
90{
91 struct hvc_struct *hp;
92
93 /* probed with invalid parameters. */
94 if (!vdev || !id)
95 return -EPERM;
96
97 hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
98 MAX_VIO_PUT_CHARS);
99 if (IS_ERR(hp))
100 return PTR_ERR(hp);
101 dev_set_drvdata(&vdev->dev, hp);
102
103 return 0;
104}
105
106static int __devexit hvc_vio_remove(struct vio_dev *vdev)
107{
108 struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
109
110 return hvc_remove(hp);
111}
112
113static struct vio_driver hvc_vio_driver = {
114 .id_table = hvc_driver_table,
115 .probe = hvc_vio_probe,
116 .remove = __devexit_p(hvc_vio_remove),
117 .driver = {
118 .name = hvc_driver_name,
119 .owner = THIS_MODULE,
120 }
121};
122
123static int __init hvc_vio_init(void)
124{
125 int rc;
126
127 if (firmware_has_feature(FW_FEATURE_ISERIES))
128 return -EIO;
129
130 /* Register as a vio device to receive callbacks */
131 rc = vio_register_driver(&hvc_vio_driver);
132
133 return rc;
134}
135module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
136
137static void __exit hvc_vio_exit(void)
138{
139 vio_unregister_driver(&hvc_vio_driver);
140}
141module_exit(hvc_vio_exit);
142
143/* the device tree order defines our numbering */
144static int hvc_find_vtys(void)
145{
146 struct device_node *vty;
147 int num_found = 0;
148
149 for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
150 vty = of_find_node_by_name(vty, "vty")) {
151 const uint32_t *vtermno;
152
153 /* We have statically defined space for only a certain number
154 * of console adapters.
155 */
156 if (num_found >= MAX_NR_HVC_CONSOLES) {
157 of_node_put(vty);
158 break;
159 }
160
161 vtermno = of_get_property(vty, "reg", NULL);
162 if (!vtermno)
163 continue;
164
165 if (of_device_is_compatible(vty, "hvterm1")) {
166 hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
167 ++num_found;
168 }
169 }
170
171 return num_found;
172}
173console_initcall(hvc_find_vtys);
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
new file mode 100644
index 000000000000..3740e327f180
--- /dev/null
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -0,0 +1,271 @@
1/*
2 * xen console driver interface to hvc_console.c
3 *
4 * (c) 2007 Gerd Hoffmann <kraxel@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/console.h>
22#include <linux/delay.h>
23#include <linux/err.h>
24#include <linux/init.h>
25#include <linux/types.h>
26
27#include <asm/xen/hypervisor.h>
28
29#include <xen/xen.h>
30#include <xen/page.h>
31#include <xen/events.h>
32#include <xen/interface/io/console.h>
33#include <xen/hvc-console.h>
34
35#include "hvc_console.h"
36
37#define HVC_COOKIE 0x58656e /* "Xen" in hex */
38
39static struct hvc_struct *hvc;
40static int xencons_irq;
41
42/* ------------------------------------------------------------------ */
43
44static unsigned long console_pfn = ~0ul;
45
46static inline struct xencons_interface *xencons_interface(void)
47{
48 if (console_pfn == ~0ul)
49 return mfn_to_virt(xen_start_info->console.domU.mfn);
50 else
51 return __va(console_pfn << PAGE_SHIFT);
52}
53
54static inline void notify_daemon(void)
55{
56 /* Use evtchn: this is called early, before irq is set up. */
57 notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
58}
59
60static int __write_console(const char *data, int len)
61{
62 struct xencons_interface *intf = xencons_interface();
63 XENCONS_RING_IDX cons, prod;
64 int sent = 0;
65
66 cons = intf->out_cons;
67 prod = intf->out_prod;
68 mb(); /* update queue values before going on */
69 BUG_ON((prod - cons) > sizeof(intf->out));
70
71 while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
72 intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
73
74 wmb(); /* write ring before updating pointer */
75 intf->out_prod = prod;
76
77 if (sent)
78 notify_daemon();
79 return sent;
80}
81
82static int domU_write_console(uint32_t vtermno, const char *data, int len)
83{
84 int ret = len;
85
86 /*
87 * Make sure the whole buffer is emitted, polling if
88 * necessary. We don't ever want to rely on the hvc daemon
89 * because the most interesting console output is when the
90 * kernel is crippled.
91 */
92 while (len) {
93 int sent = __write_console(data, len);
94
95 data += sent;
96 len -= sent;
97
98 if (unlikely(len))
99 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
100 }
101
102 return ret;
103}
104
105static int domU_read_console(uint32_t vtermno, char *buf, int len)
106{
107 struct xencons_interface *intf = xencons_interface();
108 XENCONS_RING_IDX cons, prod;
109 int recv = 0;
110
111 cons = intf->in_cons;
112 prod = intf->in_prod;
113 mb(); /* get pointers before reading ring */
114 BUG_ON((prod - cons) > sizeof(intf->in));
115
116 while (cons != prod && recv < len)
117 buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
118
119 mb(); /* read ring before consuming */
120 intf->in_cons = cons;
121
122 notify_daemon();
123 return recv;
124}
125
126static struct hv_ops domU_hvc_ops = {
127 .get_chars = domU_read_console,
128 .put_chars = domU_write_console,
129 .notifier_add = notifier_add_irq,
130 .notifier_del = notifier_del_irq,
131 .notifier_hangup = notifier_hangup_irq,
132};
133
134static int dom0_read_console(uint32_t vtermno, char *buf, int len)
135{
136 return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
137}
138
139/*
140 * Either for a dom0 to write to the system console, or a domU with a
141 * debug version of Xen
142 */
143static int dom0_write_console(uint32_t vtermno, const char *str, int len)
144{
145 int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
146 if (rc < 0)
147 return 0;
148
149 return len;
150}
151
152static struct hv_ops dom0_hvc_ops = {
153 .get_chars = dom0_read_console,
154 .put_chars = dom0_write_console,
155 .notifier_add = notifier_add_irq,
156 .notifier_del = notifier_del_irq,
157 .notifier_hangup = notifier_hangup_irq,
158};
159
160static int __init xen_hvc_init(void)
161{
162 struct hvc_struct *hp;
163 struct hv_ops *ops;
164
165 if (!xen_pv_domain())
166 return -ENODEV;
167
168 if (xen_initial_domain()) {
169 ops = &dom0_hvc_ops;
170 xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
171 } else {
172 if (!xen_start_info->console.domU.evtchn)
173 return -ENODEV;
174
175 ops = &domU_hvc_ops;
176 xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
177 }
178 if (xencons_irq < 0)
179 xencons_irq = 0; /* NO_IRQ */
180
181 hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
182 if (IS_ERR(hp))
183 return PTR_ERR(hp);
184
185 hvc = hp;
186
187 console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn);
188
189 return 0;
190}
191
192void xen_console_resume(void)
193{
194 if (xencons_irq)
195 rebind_evtchn_irq(xen_start_info->console.domU.evtchn, xencons_irq);
196}
197
198static void __exit xen_hvc_fini(void)
199{
200 if (hvc)
201 hvc_remove(hvc);
202}
203
204static int xen_cons_init(void)
205{
206 struct hv_ops *ops;
207
208 if (!xen_pv_domain())
209 return 0;
210
211 if (xen_initial_domain())
212 ops = &dom0_hvc_ops;
213 else
214 ops = &domU_hvc_ops;
215
216 hvc_instantiate(HVC_COOKIE, 0, ops);
217 return 0;
218}
219
220module_init(xen_hvc_init);
221module_exit(xen_hvc_fini);
222console_initcall(xen_cons_init);
223
224#ifdef CONFIG_EARLY_PRINTK
225static void xenboot_write_console(struct console *console, const char *string,
226 unsigned len)
227{
228 unsigned int linelen, off = 0;
229 const char *pos;
230
231 dom0_write_console(0, string, len);
232
233 if (xen_initial_domain())
234 return;
235
236 domU_write_console(0, "(early) ", 8);
237 while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
238 linelen = pos-string+off;
239 if (off + linelen > len)
240 break;
241 domU_write_console(0, string+off, linelen);
242 domU_write_console(0, "\r\n", 2);
243 off += linelen + 1;
244 }
245 if (off < len)
246 domU_write_console(0, string+off, len-off);
247}
248
249struct console xenboot_console = {
250 .name = "xenboot",
251 .write = xenboot_write_console,
252 .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
253};
254#endif /* CONFIG_EARLY_PRINTK */
255
256void xen_raw_console_write(const char *str)
257{
258 dom0_write_console(0, str, strlen(str));
259}
260
261void xen_raw_printk(const char *fmt, ...)
262{
263 static char buf[512];
264 va_list ap;
265
266 va_start(ap, fmt);
267 vsnprintf(buf, sizeof(buf), fmt, ap);
268 va_end(ap);
269
270 xen_raw_console_write(buf);
271}
diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
new file mode 100644
index 000000000000..bedc6c1b6fa5
--- /dev/null
+++ b/drivers/tty/hvc/hvcs.c
@@ -0,0 +1,1604 @@
1/*
2 * IBM eServer Hypervisor Virtual Console Server Device Driver
3 * Copyright (C) 2003, 2004 IBM Corp.
4 * Ryan S. Arnold (rsa@us.ibm.com)
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 * Author(s) : Ryan S. Arnold <rsa@us.ibm.com>
21 *
22 * This is the device driver for the IBM Hypervisor Virtual Console Server,
23 * "hvcs". The IBM hvcs provides a tty driver interface to allow Linux
24 * user space applications access to the system consoles of logically
25 * partitioned operating systems, e.g. Linux, running on the same partitioned
26 * Power5 ppc64 system. Physical hardware consoles per partition are not
27 * practical on this hardware so system consoles are accessed by this driver
28 * using inter-partition firmware interfaces to virtual terminal devices.
29 *
30 * A vty is known to the HMC as a "virtual serial server adapter". It is a
31 * virtual terminal device that is created by firmware upon partition creation
32 * to act as a partitioned OS's console device.
33 *
34 * Firmware dynamically (via hotplug) exposes vty-servers to a running ppc64
35 * Linux system upon their creation by the HMC or their exposure during boot.
36 * The non-user interactive backend of this driver is implemented as a vio
37 * device driver so that it can receive notification of vty-server lifetimes
38 * after it registers with the vio bus to handle vty-server probe and remove
39 * callbacks.
40 *
41 * Many vty-servers can be configured to connect to one vty, but a vty can
42 * only be actively connected to by a single vty-server, in any manner, at one
43 * time. If the HMC is currently hosting the console for a target Linux
44 * partition; attempts to open the tty device to the partition's console using
45 * the hvcs on any partition will return -EBUSY with every open attempt until
46 * the HMC frees the connection between its vty-server and the desired
47 * partition's vty device. Conversely, a vty-server may only be connected to
48 * a single vty at one time even though it may have several configured vty
49 * partner possibilities.
50 *
51 * Firmware does not provide notification of vty partner changes to this
52 * driver. This means that an HMC Super Admin may add or remove partner vtys
53 * from a vty-server's partner list but the changes will not be signaled to
54 * the vty-server. Firmware only notifies the driver when a vty-server is
55 * added or removed from the system. To compensate for this deficiency, this
56 * driver implements a sysfs update attribute which provides a method for
57 * rescanning partner information upon a user's request.
58 *
59 * Each vty-server, prior to being exposed to this driver is reference counted
60 * using the 2.6 Linux kernel kref construct.
61 *
62 * For direction on installation and usage of this driver please reference
63 * Documentation/powerpc/hvcs.txt.
64 */
65
66#include <linux/device.h>
67#include <linux/init.h>
68#include <linux/interrupt.h>
69#include <linux/kernel.h>
70#include <linux/kref.h>
71#include <linux/kthread.h>
72#include <linux/list.h>
73#include <linux/major.h>
74#include <linux/module.h>
75#include <linux/moduleparam.h>
76#include <linux/sched.h>
77#include <linux/slab.h>
78#include <linux/spinlock.h>
79#include <linux/stat.h>
80#include <linux/tty.h>
81#include <linux/tty_flip.h>
82#include <asm/hvconsole.h>
83#include <asm/hvcserver.h>
84#include <asm/uaccess.h>
85#include <asm/vio.h>
86
87/*
88 * 1.3.0 -> 1.3.1 In hvcs_open memset(..,0x00,..) instead of memset(..,0x3F,00).
89 * Removed braces around single statements following conditionals. Removed '=
90 * 0' after static int declarations since these default to zero. Removed
91 * list_for_each_safe() and replaced with list_for_each_entry() in
92 * hvcs_get_by_index(). The 'safe' version is un-needed now that the driver is
93 * using spinlocks. Changed spin_lock_irqsave() to spin_lock() when locking
94 * hvcs_structs_lock and hvcs_pi_lock since these are not touched in an int
95 * handler. Initialized hvcs_structs_lock and hvcs_pi_lock to
96 * SPIN_LOCK_UNLOCKED at declaration time rather than in hvcs_module_init().
97 * Added spin_lock around list_del() in destroy_hvcs_struct() to protect the
98 * list traversals from a deletion. Removed '= NULL' from pointer declaration
99 * statements since they are initialized NULL by default. Removed wmb()
100 * instances from hvcs_try_write(). They probably aren't needed with locking in
101 * place. Added check and cleanup for hvcs_pi_buff = kmalloc() in
102 * hvcs_module_init(). Exposed hvcs_struct.index via a sysfs attribute so that
103 * the coupling between /dev/hvcs* and a vty-server can be automatically
104 * determined. Moved kobject_put() in hvcs_open outside of the
105 * spin_unlock_irqrestore().
106 *
107 * 1.3.1 -> 1.3.2 Changed method for determining hvcs_struct->index and had it
108 * align with how the tty layer always assigns the lowest index available. This
109 * change resulted in a list of ints that denotes which indexes are available.
110 * Device additions and removals use the new hvcs_get_index() and
111 * hvcs_return_index() helper functions. The list is created with
112 * hvsc_alloc_index_list() and it is destroyed with hvcs_free_index_list().
113 * Without these fixes hotplug vty-server adapter support goes crazy with this
114 * driver if the user removes a vty-server adapter. Moved free_irq() outside of
115 * the hvcs_final_close() function in order to get it out of the spinlock.
116 * Rearranged hvcs_close(). Cleaned up some printks and did some housekeeping
117 * on the changelog. Removed local CLC_LENGTH and used HVCS_CLC_LENGTH from
118 * arch/powerepc/include/asm/hvcserver.h
119 *
120 * 1.3.2 -> 1.3.3 Replaced yield() in hvcs_close() with tty_wait_until_sent() to
121 * prevent possible lockup with realtime scheduling as similarily pointed out by
122 * akpm in hvc_console. Changed resulted in the removal of hvcs_final_close()
123 * to reorder cleanup operations and prevent discarding of pending data during
124 * an hvcs_close(). Removed spinlock protection of hvcs_struct data members in
125 * hvcs_write_room() and hvcs_chars_in_buffer() because they aren't needed.
126 */
127
128#define HVCS_DRIVER_VERSION "1.3.3"
129
130MODULE_AUTHOR("Ryan S. Arnold <rsa@us.ibm.com>");
131MODULE_DESCRIPTION("IBM hvcs (Hypervisor Virtual Console Server) Driver");
132MODULE_LICENSE("GPL");
133MODULE_VERSION(HVCS_DRIVER_VERSION);
134
135/*
136 * Wait this long per iteration while trying to push buffered data to the
137 * hypervisor before allowing the tty to complete a close operation.
138 */
139#define HVCS_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
140
141/*
142 * Since the Linux TTY code does not currently (2-04-2004) support dynamic
143 * addition of tty derived devices and we shouldn't allocate thousands of
144 * tty_device pointers when the number of vty-server & vty partner connections
145 * will most often be much lower than this, we'll arbitrarily allocate
146 * HVCS_DEFAULT_SERVER_ADAPTERS tty_structs and cdev's by default when we
147 * register the tty_driver. This can be overridden using an insmod parameter.
148 */
149#define HVCS_DEFAULT_SERVER_ADAPTERS 64
150
151/*
152 * The user can't insmod with more than HVCS_MAX_SERVER_ADAPTERS hvcs device
153 * nodes as a sanity check. Theoretically there can be over 1 Billion
154 * vty-server & vty partner connections.
155 */
156#define HVCS_MAX_SERVER_ADAPTERS 1024
157
158/*
159 * We let Linux assign us a major number and we start the minors at zero. There
160 * is no intuitive mapping between minor number and the target vty-server
161 * adapter except that each new vty-server adapter is always assigned to the
162 * smallest minor number available.
163 */
164#define HVCS_MINOR_START 0
165
166/*
167 * The hcall interface involves putting 8 chars into each of two registers.
168 * We load up those 2 registers (in arch/powerpc/platforms/pseries/hvconsole.c)
169 * by casting char[16] to long[2]. It would work without __ALIGNED__, but a
170 * little (tiny) bit slower because an unaligned load is slower than aligned
171 * load.
172 */
173#define __ALIGNED__ __attribute__((__aligned__(8)))
174
175/*
176 * How much data can firmware send with each hvc_put_chars()? Maybe this
177 * should be moved into an architecture specific area.
178 */
179#define HVCS_BUFF_LEN 16
180
181/*
182 * This is the maximum amount of data we'll let the user send us (hvcs_write) at
183 * once in a chunk as a sanity check.
184 */
185#define HVCS_MAX_FROM_USER 4096
186
187/*
188 * Be careful when adding flags to this line discipline. Don't add anything
189 * that will cause echoing or we'll go into recursive loop echoing chars back
190 * and forth with the console drivers.
191 */
192static struct ktermios hvcs_tty_termios = {
193 .c_iflag = IGNBRK | IGNPAR,
194 .c_oflag = OPOST,
195 .c_cflag = B38400 | CS8 | CREAD | HUPCL,
196 .c_cc = INIT_C_CC,
197 .c_ispeed = 38400,
198 .c_ospeed = 38400
199};
200
201/*
202 * This value is used to take the place of a command line parameter when the
203 * module is inserted. It starts as -1 and stays as such if the user doesn't
204 * specify a module insmod parameter. If they DO specify one then it is set to
205 * the value of the integer passed in.
206 */
207static int hvcs_parm_num_devs = -1;
208module_param(hvcs_parm_num_devs, int, 0);
209
210static const char hvcs_driver_name[] = "hvcs";
211static const char hvcs_device_node[] = "hvcs";
212static const char hvcs_driver_string[]
213 = "IBM hvcs (Hypervisor Virtual Console Server) Driver";
214
215/* Status of partner info rescan triggered via sysfs. */
216static int hvcs_rescan_status;
217
218static struct tty_driver *hvcs_tty_driver;
219
220/*
221 * In order to be somewhat sane this driver always associates the hvcs_struct
222 * index element with the numerically equal tty->index. This means that a
223 * hotplugged vty-server adapter will always map to the lowest index valued
224 * device node. If vty-servers were hotplug removed from the system and then
225 * new ones added the new vty-server may have the largest slot number of all
226 * the vty-server adapters in the partition but it may have the lowest dev node
227 * index of all the adapters due to the hole left by the hotplug removed
228 * adapter. There are a set of functions provided to get the lowest index for
229 * a new device as well as return the index to the list. This list is allocated
230 * with a number of elements equal to the number of device nodes requested when
231 * the module was inserted.
232 */
233static int *hvcs_index_list;
234
235/*
236 * How large is the list? This is kept for traversal since the list is
237 * dynamically created.
238 */
239static int hvcs_index_count;
240
241/*
242 * Used by the khvcsd to pick up I/O operations when the kernel_thread is
243 * already awake but potentially shifted to TASK_INTERRUPTIBLE state.
244 */
245static int hvcs_kicked;
246
247/*
248 * Use by the kthread construct for task operations like waking the sleeping
249 * thread and stopping the kthread.
250 */
251static struct task_struct *hvcs_task;
252
253/*
254 * We allocate this for the use of all of the hvcs_structs when they fetch
255 * partner info.
256 */
257static unsigned long *hvcs_pi_buff;
258
259/* Only allow one hvcs_struct to use the hvcs_pi_buff at a time. */
260static DEFINE_SPINLOCK(hvcs_pi_lock);
261
262/* One vty-server per hvcs_struct */
263struct hvcs_struct {
264 spinlock_t lock;
265
266 /*
267 * This index identifies this hvcs device as the complement to a
268 * specific tty index.
269 */
270 unsigned int index;
271
272 struct tty_struct *tty;
273 int open_count;
274
275 /*
276 * Used to tell the driver kernel_thread what operations need to take
277 * place upon this hvcs_struct instance.
278 */
279 int todo_mask;
280
281 /*
282 * This buffer is required so that when hvcs_write_room() reports that
283 * it can send HVCS_BUFF_LEN characters that it will buffer the full
284 * HVCS_BUFF_LEN characters if need be. This is essential for opost
285 * writes since they do not do high level buffering and expect to be
286 * able to send what the driver commits to sending buffering
287 * [e.g. tab to space conversions in n_tty.c opost()].
288 */
289 char buffer[HVCS_BUFF_LEN];
290 int chars_in_buffer;
291
292 /*
293 * Any variable below the kref is valid before a tty is connected and
294 * stays valid after the tty is disconnected. These shouldn't be
295 * whacked until the koject refcount reaches zero though some entries
296 * may be changed via sysfs initiatives.
297 */
298 struct kref kref; /* ref count & hvcs_struct lifetime */
299 int connected; /* is the vty-server currently connected to a vty? */
300 uint32_t p_unit_address; /* partner unit address */
301 uint32_t p_partition_ID; /* partner partition ID */
302 char p_location_code[HVCS_CLC_LENGTH + 1]; /* CLC + Null Term */
303 struct list_head next; /* list management */
304 struct vio_dev *vdev;
305};
306
307/* Required to back map a kref to its containing object */
308#define from_kref(k) container_of(k, struct hvcs_struct, kref)
309
310static LIST_HEAD(hvcs_structs);
311static DEFINE_SPINLOCK(hvcs_structs_lock);
312
313static void hvcs_unthrottle(struct tty_struct *tty);
314static void hvcs_throttle(struct tty_struct *tty);
315static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance);
316
317static int hvcs_write(struct tty_struct *tty,
318 const unsigned char *buf, int count);
319static int hvcs_write_room(struct tty_struct *tty);
320static int hvcs_chars_in_buffer(struct tty_struct *tty);
321
322static int hvcs_has_pi(struct hvcs_struct *hvcsd);
323static void hvcs_set_pi(struct hvcs_partner_info *pi,
324 struct hvcs_struct *hvcsd);
325static int hvcs_get_pi(struct hvcs_struct *hvcsd);
326static int hvcs_rescan_devices_list(void);
327
328static int hvcs_partner_connect(struct hvcs_struct *hvcsd);
329static void hvcs_partner_free(struct hvcs_struct *hvcsd);
330
331static int hvcs_enable_device(struct hvcs_struct *hvcsd,
332 uint32_t unit_address, unsigned int irq, struct vio_dev *dev);
333
334static int hvcs_open(struct tty_struct *tty, struct file *filp);
335static void hvcs_close(struct tty_struct *tty, struct file *filp);
336static void hvcs_hangup(struct tty_struct * tty);
337
338static int __devinit hvcs_probe(struct vio_dev *dev,
339 const struct vio_device_id *id);
340static int __devexit hvcs_remove(struct vio_dev *dev);
341static int __init hvcs_module_init(void);
342static void __exit hvcs_module_exit(void);
343
344#define HVCS_SCHED_READ 0x00000001
345#define HVCS_QUICK_READ 0x00000002
346#define HVCS_TRY_WRITE 0x00000004
347#define HVCS_READ_MASK (HVCS_SCHED_READ | HVCS_QUICK_READ)
348
349static inline struct hvcs_struct *from_vio_dev(struct vio_dev *viod)
350{
351 return dev_get_drvdata(&viod->dev);
352}
353/* The sysfs interface for the driver and devices */
354
355static ssize_t hvcs_partner_vtys_show(struct device *dev, struct device_attribute *attr, char *buf)
356{
357 struct vio_dev *viod = to_vio_dev(dev);
358 struct hvcs_struct *hvcsd = from_vio_dev(viod);
359 unsigned long flags;
360 int retval;
361
362 spin_lock_irqsave(&hvcsd->lock, flags);
363 retval = sprintf(buf, "%X\n", hvcsd->p_unit_address);
364 spin_unlock_irqrestore(&hvcsd->lock, flags);
365 return retval;
366}
367static DEVICE_ATTR(partner_vtys, S_IRUGO, hvcs_partner_vtys_show, NULL);
368
369static ssize_t hvcs_partner_clcs_show(struct device *dev, struct device_attribute *attr, char *buf)
370{
371 struct vio_dev *viod = to_vio_dev(dev);
372 struct hvcs_struct *hvcsd = from_vio_dev(viod);
373 unsigned long flags;
374 int retval;
375
376 spin_lock_irqsave(&hvcsd->lock, flags);
377 retval = sprintf(buf, "%s\n", &hvcsd->p_location_code[0]);
378 spin_unlock_irqrestore(&hvcsd->lock, flags);
379 return retval;
380}
381static DEVICE_ATTR(partner_clcs, S_IRUGO, hvcs_partner_clcs_show, NULL);
382
383static ssize_t hvcs_current_vty_store(struct device *dev, struct device_attribute *attr, const char * buf,
384 size_t count)
385{
386 /*
387 * Don't need this feature at the present time because firmware doesn't
388 * yet support multiple partners.
389 */
390 printk(KERN_INFO "HVCS: Denied current_vty change: -EPERM.\n");
391 return -EPERM;
392}
393
394static ssize_t hvcs_current_vty_show(struct device *dev, struct device_attribute *attr, char *buf)
395{
396 struct vio_dev *viod = to_vio_dev(dev);
397 struct hvcs_struct *hvcsd = from_vio_dev(viod);
398 unsigned long flags;
399 int retval;
400
401 spin_lock_irqsave(&hvcsd->lock, flags);
402 retval = sprintf(buf, "%s\n", &hvcsd->p_location_code[0]);
403 spin_unlock_irqrestore(&hvcsd->lock, flags);
404 return retval;
405}
406
407static DEVICE_ATTR(current_vty,
408 S_IRUGO | S_IWUSR, hvcs_current_vty_show, hvcs_current_vty_store);
409
410static ssize_t hvcs_vterm_state_store(struct device *dev, struct device_attribute *attr, const char *buf,
411 size_t count)
412{
413 struct vio_dev *viod = to_vio_dev(dev);
414 struct hvcs_struct *hvcsd = from_vio_dev(viod);
415 unsigned long flags;
416
417 /* writing a '0' to this sysfs entry will result in the disconnect. */
418 if (simple_strtol(buf, NULL, 0) != 0)
419 return -EINVAL;
420
421 spin_lock_irqsave(&hvcsd->lock, flags);
422
423 if (hvcsd->open_count > 0) {
424 spin_unlock_irqrestore(&hvcsd->lock, flags);
425 printk(KERN_INFO "HVCS: vterm state unchanged. "
426 "The hvcs device node is still in use.\n");
427 return -EPERM;
428 }
429
430 if (hvcsd->connected == 0) {
431 spin_unlock_irqrestore(&hvcsd->lock, flags);
432 printk(KERN_INFO "HVCS: vterm state unchanged. The"
433 " vty-server is not connected to a vty.\n");
434 return -EPERM;
435 }
436
437 hvcs_partner_free(hvcsd);
438 printk(KERN_INFO "HVCS: Closed vty-server@%X and"
439 " partner vty@%X:%d connection.\n",
440 hvcsd->vdev->unit_address,
441 hvcsd->p_unit_address,
442 (uint32_t)hvcsd->p_partition_ID);
443
444 spin_unlock_irqrestore(&hvcsd->lock, flags);
445 return count;
446}
447
448static ssize_t hvcs_vterm_state_show(struct device *dev, struct device_attribute *attr, char *buf)
449{
450 struct vio_dev *viod = to_vio_dev(dev);
451 struct hvcs_struct *hvcsd = from_vio_dev(viod);
452 unsigned long flags;
453 int retval;
454
455 spin_lock_irqsave(&hvcsd->lock, flags);
456 retval = sprintf(buf, "%d\n", hvcsd->connected);
457 spin_unlock_irqrestore(&hvcsd->lock, flags);
458 return retval;
459}
460static DEVICE_ATTR(vterm_state, S_IRUGO | S_IWUSR,
461 hvcs_vterm_state_show, hvcs_vterm_state_store);
462
463static ssize_t hvcs_index_show(struct device *dev, struct device_attribute *attr, char *buf)
464{
465 struct vio_dev *viod = to_vio_dev(dev);
466 struct hvcs_struct *hvcsd = from_vio_dev(viod);
467 unsigned long flags;
468 int retval;
469
470 spin_lock_irqsave(&hvcsd->lock, flags);
471 retval = sprintf(buf, "%d\n", hvcsd->index);
472 spin_unlock_irqrestore(&hvcsd->lock, flags);
473 return retval;
474}
475
476static DEVICE_ATTR(index, S_IRUGO, hvcs_index_show, NULL);
477
478static struct attribute *hvcs_attrs[] = {
479 &dev_attr_partner_vtys.attr,
480 &dev_attr_partner_clcs.attr,
481 &dev_attr_current_vty.attr,
482 &dev_attr_vterm_state.attr,
483 &dev_attr_index.attr,
484 NULL,
485};
486
487static struct attribute_group hvcs_attr_group = {
488 .attrs = hvcs_attrs,
489};
490
491static ssize_t hvcs_rescan_show(struct device_driver *ddp, char *buf)
492{
493 /* A 1 means it is updating, a 0 means it is done updating */
494 return snprintf(buf, PAGE_SIZE, "%d\n", hvcs_rescan_status);
495}
496
497static ssize_t hvcs_rescan_store(struct device_driver *ddp, const char * buf,
498 size_t count)
499{
500 if ((simple_strtol(buf, NULL, 0) != 1)
501 && (hvcs_rescan_status != 0))
502 return -EINVAL;
503
504 hvcs_rescan_status = 1;
505 printk(KERN_INFO "HVCS: rescanning partner info for all"
506 " vty-servers.\n");
507 hvcs_rescan_devices_list();
508 hvcs_rescan_status = 0;
509 return count;
510}
511
512static DRIVER_ATTR(rescan,
513 S_IRUGO | S_IWUSR, hvcs_rescan_show, hvcs_rescan_store);
514
515static void hvcs_kick(void)
516{
517 hvcs_kicked = 1;
518 wmb();
519 wake_up_process(hvcs_task);
520}
521
522static void hvcs_unthrottle(struct tty_struct *tty)
523{
524 struct hvcs_struct *hvcsd = tty->driver_data;
525 unsigned long flags;
526
527 spin_lock_irqsave(&hvcsd->lock, flags);
528 hvcsd->todo_mask |= HVCS_SCHED_READ;
529 spin_unlock_irqrestore(&hvcsd->lock, flags);
530 hvcs_kick();
531}
532
533static void hvcs_throttle(struct tty_struct *tty)
534{
535 struct hvcs_struct *hvcsd = tty->driver_data;
536 unsigned long flags;
537
538 spin_lock_irqsave(&hvcsd->lock, flags);
539 vio_disable_interrupts(hvcsd->vdev);
540 spin_unlock_irqrestore(&hvcsd->lock, flags);
541}
542
543/*
544 * If the device is being removed we don't have to worry about this interrupt
545 * handler taking any further interrupts because they are disabled which means
546 * the hvcs_struct will always be valid in this handler.
547 */
548static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance)
549{
550 struct hvcs_struct *hvcsd = dev_instance;
551
552 spin_lock(&hvcsd->lock);
553 vio_disable_interrupts(hvcsd->vdev);
554 hvcsd->todo_mask |= HVCS_SCHED_READ;
555 spin_unlock(&hvcsd->lock);
556 hvcs_kick();
557
558 return IRQ_HANDLED;
559}
560
561/* This function must be called with the hvcsd->lock held */
562static void hvcs_try_write(struct hvcs_struct *hvcsd)
563{
564 uint32_t unit_address = hvcsd->vdev->unit_address;
565 struct tty_struct *tty = hvcsd->tty;
566 int sent;
567
568 if (hvcsd->todo_mask & HVCS_TRY_WRITE) {
569 /* won't send partial writes */
570 sent = hvc_put_chars(unit_address,
571 &hvcsd->buffer[0],
572 hvcsd->chars_in_buffer );
573 if (sent > 0) {
574 hvcsd->chars_in_buffer = 0;
575 /* wmb(); */
576 hvcsd->todo_mask &= ~(HVCS_TRY_WRITE);
577 /* wmb(); */
578
579 /*
580 * We are still obligated to deliver the data to the
581 * hypervisor even if the tty has been closed because
582 * we commited to delivering it. But don't try to wake
583 * a non-existent tty.
584 */
585 if (tty) {
586 tty_wakeup(tty);
587 }
588 }
589 }
590}
591
592static int hvcs_io(struct hvcs_struct *hvcsd)
593{
594 uint32_t unit_address;
595 struct tty_struct *tty;
596 char buf[HVCS_BUFF_LEN] __ALIGNED__;
597 unsigned long flags;
598 int got = 0;
599
600 spin_lock_irqsave(&hvcsd->lock, flags);
601
602 unit_address = hvcsd->vdev->unit_address;
603 tty = hvcsd->tty;
604
605 hvcs_try_write(hvcsd);
606
607 if (!tty || test_bit(TTY_THROTTLED, &tty->flags)) {
608 hvcsd->todo_mask &= ~(HVCS_READ_MASK);
609 goto bail;
610 } else if (!(hvcsd->todo_mask & (HVCS_READ_MASK)))
611 goto bail;
612
613 /* remove the read masks */
614 hvcsd->todo_mask &= ~(HVCS_READ_MASK);
615
616 if (tty_buffer_request_room(tty, HVCS_BUFF_LEN) >= HVCS_BUFF_LEN) {
617 got = hvc_get_chars(unit_address,
618 &buf[0],
619 HVCS_BUFF_LEN);
620 tty_insert_flip_string(tty, buf, got);
621 }
622
623 /* Give the TTY time to process the data we just sent. */
624 if (got)
625 hvcsd->todo_mask |= HVCS_QUICK_READ;
626
627 spin_unlock_irqrestore(&hvcsd->lock, flags);
628 /* This is synch because tty->low_latency == 1 */
629 if(got)
630 tty_flip_buffer_push(tty);
631
632 if (!got) {
633 /* Do this _after_ the flip_buffer_push */
634 spin_lock_irqsave(&hvcsd->lock, flags);
635 vio_enable_interrupts(hvcsd->vdev);
636 spin_unlock_irqrestore(&hvcsd->lock, flags);
637 }
638
639 return hvcsd->todo_mask;
640
641 bail:
642 spin_unlock_irqrestore(&hvcsd->lock, flags);
643 return hvcsd->todo_mask;
644}
645
646static int khvcsd(void *unused)
647{
648 struct hvcs_struct *hvcsd;
649 int hvcs_todo_mask;
650
651 __set_current_state(TASK_RUNNING);
652
653 do {
654 hvcs_todo_mask = 0;
655 hvcs_kicked = 0;
656 wmb();
657
658 spin_lock(&hvcs_structs_lock);
659 list_for_each_entry(hvcsd, &hvcs_structs, next) {
660 hvcs_todo_mask |= hvcs_io(hvcsd);
661 }
662 spin_unlock(&hvcs_structs_lock);
663
664 /*
665 * If any of the hvcs adapters want to try a write or quick read
666 * don't schedule(), yield a smidgen then execute the hvcs_io
667 * thread again for those that want the write.
668 */
669 if (hvcs_todo_mask & (HVCS_TRY_WRITE | HVCS_QUICK_READ)) {
670 yield();
671 continue;
672 }
673
674 set_current_state(TASK_INTERRUPTIBLE);
675 if (!hvcs_kicked)
676 schedule();
677 __set_current_state(TASK_RUNNING);
678 } while (!kthread_should_stop());
679
680 return 0;
681}
682
683static struct vio_device_id hvcs_driver_table[] __devinitdata= {
684 {"serial-server", "hvterm2"},
685 { "", "" }
686};
687MODULE_DEVICE_TABLE(vio, hvcs_driver_table);
688
689static void hvcs_return_index(int index)
690{
691 /* Paranoia check */
692 if (!hvcs_index_list)
693 return;
694 if (index < 0 || index >= hvcs_index_count)
695 return;
696 if (hvcs_index_list[index] == -1)
697 return;
698 else
699 hvcs_index_list[index] = -1;
700}
701
702/* callback when the kref ref count reaches zero */
703static void destroy_hvcs_struct(struct kref *kref)
704{
705 struct hvcs_struct *hvcsd = from_kref(kref);
706 struct vio_dev *vdev;
707 unsigned long flags;
708
709 spin_lock(&hvcs_structs_lock);
710 spin_lock_irqsave(&hvcsd->lock, flags);
711
712 /* the list_del poisons the pointers */
713 list_del(&(hvcsd->next));
714
715 if (hvcsd->connected == 1) {
716 hvcs_partner_free(hvcsd);
717 printk(KERN_INFO "HVCS: Closed vty-server@%X and"
718 " partner vty@%X:%d connection.\n",
719 hvcsd->vdev->unit_address,
720 hvcsd->p_unit_address,
721 (uint32_t)hvcsd->p_partition_ID);
722 }
723 printk(KERN_INFO "HVCS: Destroyed hvcs_struct for vty-server@%X.\n",
724 hvcsd->vdev->unit_address);
725
726 vdev = hvcsd->vdev;
727 hvcsd->vdev = NULL;
728
729 hvcsd->p_unit_address = 0;
730 hvcsd->p_partition_ID = 0;
731 hvcs_return_index(hvcsd->index);
732 memset(&hvcsd->p_location_code[0], 0x00, HVCS_CLC_LENGTH + 1);
733
734 spin_unlock_irqrestore(&hvcsd->lock, flags);
735 spin_unlock(&hvcs_structs_lock);
736
737 sysfs_remove_group(&vdev->dev.kobj, &hvcs_attr_group);
738
739 kfree(hvcsd);
740}
741
742static int hvcs_get_index(void)
743{
744 int i;
745 /* Paranoia check */
746 if (!hvcs_index_list) {
747 printk(KERN_ERR "HVCS: hvcs_index_list NOT valid!.\n");
748 return -EFAULT;
749 }
750 /* Find the numerically lowest first free index. */
751 for(i = 0; i < hvcs_index_count; i++) {
752 if (hvcs_index_list[i] == -1) {
753 hvcs_index_list[i] = 0;
754 return i;
755 }
756 }
757 return -1;
758}
759
760static int __devinit hvcs_probe(
761 struct vio_dev *dev,
762 const struct vio_device_id *id)
763{
764 struct hvcs_struct *hvcsd;
765 int index;
766 int retval;
767
768 if (!dev || !id) {
769 printk(KERN_ERR "HVCS: probed with invalid parameter.\n");
770 return -EPERM;
771 }
772
773 /* early to avoid cleanup on failure */
774 index = hvcs_get_index();
775 if (index < 0) {
776 return -EFAULT;
777 }
778
779 hvcsd = kzalloc(sizeof(*hvcsd), GFP_KERNEL);
780 if (!hvcsd)
781 return -ENODEV;
782
783
784 spin_lock_init(&hvcsd->lock);
785 /* Automatically incs the refcount the first time */
786 kref_init(&hvcsd->kref);
787
788 hvcsd->vdev = dev;
789 dev_set_drvdata(&dev->dev, hvcsd);
790
791 hvcsd->index = index;
792
793 /* hvcsd->index = ++hvcs_struct_count; */
794 hvcsd->chars_in_buffer = 0;
795 hvcsd->todo_mask = 0;
796 hvcsd->connected = 0;
797
798 /*
799 * This will populate the hvcs_struct's partner info fields for the
800 * first time.
801 */
802 if (hvcs_get_pi(hvcsd)) {
803 printk(KERN_ERR "HVCS: Failed to fetch partner"
804 " info for vty-server@%X on device probe.\n",
805 hvcsd->vdev->unit_address);
806 }
807
808 /*
809 * If a user app opens a tty that corresponds to this vty-server before
810 * the hvcs_struct has been added to the devices list then the user app
811 * will get -ENODEV.
812 */
813 spin_lock(&hvcs_structs_lock);
814 list_add_tail(&(hvcsd->next), &hvcs_structs);
815 spin_unlock(&hvcs_structs_lock);
816
817 retval = sysfs_create_group(&dev->dev.kobj, &hvcs_attr_group);
818 if (retval) {
819 printk(KERN_ERR "HVCS: Can't create sysfs attrs for vty-server@%X\n",
820 hvcsd->vdev->unit_address);
821 return retval;
822 }
823
824 printk(KERN_INFO "HVCS: vty-server@%X added to the vio bus.\n", dev->unit_address);
825
826 /*
827 * DON'T enable interrupts here because there is no user to receive the
828 * data.
829 */
830 return 0;
831}
832
833static int __devexit hvcs_remove(struct vio_dev *dev)
834{
835 struct hvcs_struct *hvcsd = dev_get_drvdata(&dev->dev);
836 unsigned long flags;
837 struct tty_struct *tty;
838
839 if (!hvcsd)
840 return -ENODEV;
841
842 /* By this time the vty-server won't be getting any more interrupts */
843
844 spin_lock_irqsave(&hvcsd->lock, flags);
845
846 tty = hvcsd->tty;
847
848 spin_unlock_irqrestore(&hvcsd->lock, flags);
849
850 /*
851 * Let the last holder of this object cause it to be removed, which
852 * would probably be tty_hangup below.
853 */
854 kref_put(&hvcsd->kref, destroy_hvcs_struct);
855
856 /*
857 * The hangup is a scheduled function which will auto chain call
858 * hvcs_hangup. The tty should always be valid at this time unless a
859 * simultaneous tty close already cleaned up the hvcs_struct.
860 */
861 if (tty)
862 tty_hangup(tty);
863
864 printk(KERN_INFO "HVCS: vty-server@%X removed from the"
865 " vio bus.\n", dev->unit_address);
866 return 0;
867};
868
869static struct vio_driver hvcs_vio_driver = {
870 .id_table = hvcs_driver_table,
871 .probe = hvcs_probe,
872 .remove = __devexit_p(hvcs_remove),
873 .driver = {
874 .name = hvcs_driver_name,
875 .owner = THIS_MODULE,
876 }
877};
878
879/* Only called from hvcs_get_pi please */
880static void hvcs_set_pi(struct hvcs_partner_info *pi, struct hvcs_struct *hvcsd)
881{
882 int clclength;
883
884 hvcsd->p_unit_address = pi->unit_address;
885 hvcsd->p_partition_ID = pi->partition_ID;
886 clclength = strlen(&pi->location_code[0]);
887 if (clclength > HVCS_CLC_LENGTH)
888 clclength = HVCS_CLC_LENGTH;
889
890 /* copy the null-term char too */
891 strncpy(&hvcsd->p_location_code[0],
892 &pi->location_code[0], clclength + 1);
893}
894
895/*
896 * Traverse the list and add the partner info that is found to the hvcs_struct
897 * struct entry. NOTE: At this time I know that partner info will return a
898 * single entry but in the future there may be multiple partner info entries per
899 * vty-server and you'll want to zero out that list and reset it. If for some
900 * reason you have an old version of this driver but there IS more than one
901 * partner info then hvcsd->p_* will hold the last partner info data from the
902 * firmware query. A good way to update this code would be to replace the three
903 * partner info fields in hvcs_struct with a list of hvcs_partner_info
904 * instances.
905 *
906 * This function must be called with the hvcsd->lock held.
907 */
908static int hvcs_get_pi(struct hvcs_struct *hvcsd)
909{
910 struct hvcs_partner_info *pi;
911 uint32_t unit_address = hvcsd->vdev->unit_address;
912 struct list_head head;
913 int retval;
914
915 spin_lock(&hvcs_pi_lock);
916 if (!hvcs_pi_buff) {
917 spin_unlock(&hvcs_pi_lock);
918 return -EFAULT;
919 }
920 retval = hvcs_get_partner_info(unit_address, &head, hvcs_pi_buff);
921 spin_unlock(&hvcs_pi_lock);
922 if (retval) {
923 printk(KERN_ERR "HVCS: Failed to fetch partner"
924 " info for vty-server@%x.\n", unit_address);
925 return retval;
926 }
927
928 /* nixes the values if the partner vty went away */
929 hvcsd->p_unit_address = 0;
930 hvcsd->p_partition_ID = 0;
931
932 list_for_each_entry(pi, &head, node)
933 hvcs_set_pi(pi, hvcsd);
934
935 hvcs_free_partner_info(&head);
936 return 0;
937}
938
939/*
940 * This function is executed by the driver "rescan" sysfs entry. It shouldn't
941 * be executed elsewhere, in order to prevent deadlock issues.
942 */
943static int hvcs_rescan_devices_list(void)
944{
945 struct hvcs_struct *hvcsd;
946 unsigned long flags;
947
948 spin_lock(&hvcs_structs_lock);
949
950 list_for_each_entry(hvcsd, &hvcs_structs, next) {
951 spin_lock_irqsave(&hvcsd->lock, flags);
952 hvcs_get_pi(hvcsd);
953 spin_unlock_irqrestore(&hvcsd->lock, flags);
954 }
955
956 spin_unlock(&hvcs_structs_lock);
957
958 return 0;
959}
960
961/*
962 * Farm this off into its own function because it could be more complex once
963 * multiple partners support is added. This function should be called with
964 * the hvcsd->lock held.
965 */
966static int hvcs_has_pi(struct hvcs_struct *hvcsd)
967{
968 if ((!hvcsd->p_unit_address) || (!hvcsd->p_partition_ID))
969 return 0;
970 return 1;
971}
972
973/*
974 * NOTE: It is possible that the super admin removed a partner vty and then
975 * added a different vty as the new partner.
976 *
977 * This function must be called with the hvcsd->lock held.
978 */
979static int hvcs_partner_connect(struct hvcs_struct *hvcsd)
980{
981 int retval;
982 unsigned int unit_address = hvcsd->vdev->unit_address;
983
984 /*
985 * If there wasn't any pi when the device was added it doesn't meant
986 * there isn't any now. This driver isn't notified when a new partner
987 * vty is added to a vty-server so we discover changes on our own.
988 * Please see comments in hvcs_register_connection() for justification
989 * of this bizarre code.
990 */
991 retval = hvcs_register_connection(unit_address,
992 hvcsd->p_partition_ID,
993 hvcsd->p_unit_address);
994 if (!retval) {
995 hvcsd->connected = 1;
996 return 0;
997 } else if (retval != -EINVAL)
998 return retval;
999
1000 /*
1001 * As per the spec re-get the pi and try again if -EINVAL after the
1002 * first connection attempt.
1003 */
1004 if (hvcs_get_pi(hvcsd))
1005 return -ENOMEM;
1006
1007 if (!hvcs_has_pi(hvcsd))
1008 return -ENODEV;
1009
1010 retval = hvcs_register_connection(unit_address,
1011 hvcsd->p_partition_ID,
1012 hvcsd->p_unit_address);
1013 if (retval != -EINVAL) {
1014 hvcsd->connected = 1;
1015 return retval;
1016 }
1017
1018 /*
1019 * EBUSY is the most likely scenario though the vty could have been
1020 * removed or there really could be an hcall error due to the parameter
1021 * data but thanks to ambiguous firmware return codes we can't really
1022 * tell.
1023 */
1024 printk(KERN_INFO "HVCS: vty-server or partner"
1025 " vty is busy. Try again later.\n");
1026 return -EBUSY;
1027}
1028
1029/* This function must be called with the hvcsd->lock held */
1030static void hvcs_partner_free(struct hvcs_struct *hvcsd)
1031{
1032 int retval;
1033 do {
1034 retval = hvcs_free_connection(hvcsd->vdev->unit_address);
1035 } while (retval == -EBUSY);
1036 hvcsd->connected = 0;
1037}
1038
1039/* This helper function must be called WITHOUT the hvcsd->lock held */
1040static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address,
1041 unsigned int irq, struct vio_dev *vdev)
1042{
1043 unsigned long flags;
1044 int rc;
1045
1046 /*
1047 * It is possible that the vty-server was removed between the time that
1048 * the conn was registered and now.
1049 */
1050 if (!(rc = request_irq(irq, &hvcs_handle_interrupt,
1051 IRQF_DISABLED, "ibmhvcs", hvcsd))) {
1052 /*
1053 * It is possible the vty-server was removed after the irq was
1054 * requested but before we have time to enable interrupts.
1055 */
1056 if (vio_enable_interrupts(vdev) == H_SUCCESS)
1057 return 0;
1058 else {
1059 printk(KERN_ERR "HVCS: int enable failed for"
1060 " vty-server@%X.\n", unit_address);
1061 free_irq(irq, hvcsd);
1062 }
1063 } else
1064 printk(KERN_ERR "HVCS: irq req failed for"
1065 " vty-server@%X.\n", unit_address);
1066
1067 spin_lock_irqsave(&hvcsd->lock, flags);
1068 hvcs_partner_free(hvcsd);
1069 spin_unlock_irqrestore(&hvcsd->lock, flags);
1070
1071 return rc;
1072
1073}
1074
1075/*
1076 * This always increments the kref ref count if the call is successful.
1077 * Please remember to dec when you are done with the instance.
1078 *
1079 * NOTICE: Do NOT hold either the hvcs_struct.lock or hvcs_structs_lock when
1080 * calling this function or you will get deadlock.
1081 */
1082static struct hvcs_struct *hvcs_get_by_index(int index)
1083{
1084 struct hvcs_struct *hvcsd = NULL;
1085 unsigned long flags;
1086
1087 spin_lock(&hvcs_structs_lock);
1088 /* We can immediately discard OOB requests */
1089 if (index >= 0 && index < HVCS_MAX_SERVER_ADAPTERS) {
1090 list_for_each_entry(hvcsd, &hvcs_structs, next) {
1091 spin_lock_irqsave(&hvcsd->lock, flags);
1092 if (hvcsd->index == index) {
1093 kref_get(&hvcsd->kref);
1094 spin_unlock_irqrestore(&hvcsd->lock, flags);
1095 spin_unlock(&hvcs_structs_lock);
1096 return hvcsd;
1097 }
1098 spin_unlock_irqrestore(&hvcsd->lock, flags);
1099 }
1100 hvcsd = NULL;
1101 }
1102
1103 spin_unlock(&hvcs_structs_lock);
1104 return hvcsd;
1105}
1106
1107/*
1108 * This is invoked via the tty_open interface when a user app connects to the
1109 * /dev node.
1110 */
1111static int hvcs_open(struct tty_struct *tty, struct file *filp)
1112{
1113 struct hvcs_struct *hvcsd;
1114 int rc, retval = 0;
1115 unsigned long flags;
1116 unsigned int irq;
1117 struct vio_dev *vdev;
1118 unsigned long unit_address;
1119
1120 if (tty->driver_data)
1121 goto fast_open;
1122
1123 /*
1124 * Is there a vty-server that shares the same index?
1125 * This function increments the kref index.
1126 */
1127 if (!(hvcsd = hvcs_get_by_index(tty->index))) {
1128 printk(KERN_WARNING "HVCS: open failed, no device associated"
1129 " with tty->index %d.\n", tty->index);
1130 return -ENODEV;
1131 }
1132
1133 spin_lock_irqsave(&hvcsd->lock, flags);
1134
1135 if (hvcsd->connected == 0)
1136 if ((retval = hvcs_partner_connect(hvcsd)))
1137 goto error_release;
1138
1139 hvcsd->open_count = 1;
1140 hvcsd->tty = tty;
1141 tty->driver_data = hvcsd;
1142
1143 memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN);
1144
1145 /*
1146 * Save these in the spinlock for the enable operations that need them
1147 * outside of the spinlock.
1148 */
1149 irq = hvcsd->vdev->irq;
1150 vdev = hvcsd->vdev;
1151 unit_address = hvcsd->vdev->unit_address;
1152
1153 hvcsd->todo_mask |= HVCS_SCHED_READ;
1154 spin_unlock_irqrestore(&hvcsd->lock, flags);
1155
1156 /*
1157 * This must be done outside of the spinlock because it requests irqs
1158 * and will grab the spinlock and free the connection if it fails.
1159 */
1160 if (((rc = hvcs_enable_device(hvcsd, unit_address, irq, vdev)))) {
1161 kref_put(&hvcsd->kref, destroy_hvcs_struct);
1162 printk(KERN_WARNING "HVCS: enable device failed.\n");
1163 return rc;
1164 }
1165
1166 goto open_success;
1167
1168fast_open:
1169 hvcsd = tty->driver_data;
1170
1171 spin_lock_irqsave(&hvcsd->lock, flags);
1172 kref_get(&hvcsd->kref);
1173 hvcsd->open_count++;
1174 hvcsd->todo_mask |= HVCS_SCHED_READ;
1175 spin_unlock_irqrestore(&hvcsd->lock, flags);
1176
1177open_success:
1178 hvcs_kick();
1179
1180 printk(KERN_INFO "HVCS: vty-server@%X connection opened.\n",
1181 hvcsd->vdev->unit_address );
1182
1183 return 0;
1184
1185error_release:
1186 spin_unlock_irqrestore(&hvcsd->lock, flags);
1187 kref_put(&hvcsd->kref, destroy_hvcs_struct);
1188
1189 printk(KERN_WARNING "HVCS: partner connect failed.\n");
1190 return retval;
1191}
1192
1193static void hvcs_close(struct tty_struct *tty, struct file *filp)
1194{
1195 struct hvcs_struct *hvcsd;
1196 unsigned long flags;
1197 int irq = NO_IRQ;
1198
1199 /*
1200 * Is someone trying to close the file associated with this device after
1201 * we have hung up? If so tty->driver_data wouldn't be valid.
1202 */
1203 if (tty_hung_up_p(filp))
1204 return;
1205
1206 /*
1207 * No driver_data means that this close was probably issued after a
1208 * failed hvcs_open by the tty layer's release_dev() api and we can just
1209 * exit cleanly.
1210 */
1211 if (!tty->driver_data)
1212 return;
1213
1214 hvcsd = tty->driver_data;
1215
1216 spin_lock_irqsave(&hvcsd->lock, flags);
1217 if (--hvcsd->open_count == 0) {
1218
1219 vio_disable_interrupts(hvcsd->vdev);
1220
1221 /*
1222 * NULL this early so that the kernel_thread doesn't try to
1223 * execute any operations on the TTY even though it is obligated
1224 * to deliver any pending I/O to the hypervisor.
1225 */
1226 hvcsd->tty = NULL;
1227
1228 irq = hvcsd->vdev->irq;
1229 spin_unlock_irqrestore(&hvcsd->lock, flags);
1230
1231 tty_wait_until_sent(tty, HVCS_CLOSE_WAIT);
1232
1233 /*
1234 * This line is important because it tells hvcs_open that this
1235 * device needs to be re-configured the next time hvcs_open is
1236 * called.
1237 */
1238 tty->driver_data = NULL;
1239
1240 free_irq(irq, hvcsd);
1241 kref_put(&hvcsd->kref, destroy_hvcs_struct);
1242 return;
1243 } else if (hvcsd->open_count < 0) {
1244 printk(KERN_ERR "HVCS: vty-server@%X open_count: %d"
1245 " is missmanaged.\n",
1246 hvcsd->vdev->unit_address, hvcsd->open_count);
1247 }
1248
1249 spin_unlock_irqrestore(&hvcsd->lock, flags);
1250 kref_put(&hvcsd->kref, destroy_hvcs_struct);
1251}
1252
1253static void hvcs_hangup(struct tty_struct * tty)
1254{
1255 struct hvcs_struct *hvcsd = tty->driver_data;
1256 unsigned long flags;
1257 int temp_open_count;
1258 int irq = NO_IRQ;
1259
1260 spin_lock_irqsave(&hvcsd->lock, flags);
1261 /* Preserve this so that we know how many kref refs to put */
1262 temp_open_count = hvcsd->open_count;
1263
1264 /*
1265 * Don't kref put inside the spinlock because the destruction
1266 * callback may use the spinlock and it may get called before the
1267 * spinlock has been released.
1268 */
1269 vio_disable_interrupts(hvcsd->vdev);
1270
1271 hvcsd->todo_mask = 0;
1272
1273 /* I don't think the tty needs the hvcs_struct pointer after a hangup */
1274 hvcsd->tty->driver_data = NULL;
1275 hvcsd->tty = NULL;
1276
1277 hvcsd->open_count = 0;
1278
1279 /* This will drop any buffered data on the floor which is OK in a hangup
1280 * scenario. */
1281 memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN);
1282 hvcsd->chars_in_buffer = 0;
1283
1284 irq = hvcsd->vdev->irq;
1285
1286 spin_unlock_irqrestore(&hvcsd->lock, flags);
1287
1288 free_irq(irq, hvcsd);
1289
1290 /*
1291 * We need to kref_put() for every open_count we have since the
1292 * tty_hangup() function doesn't invoke a close per open connection on a
1293 * non-console device.
1294 */
1295 while(temp_open_count) {
1296 --temp_open_count;
1297 /*
1298 * The final put will trigger destruction of the hvcs_struct.
1299 * NOTE: If this hangup was signaled from user space then the
1300 * final put will never happen.
1301 */
1302 kref_put(&hvcsd->kref, destroy_hvcs_struct);
1303 }
1304}
1305
1306/*
1307 * NOTE: This is almost always from_user since user level apps interact with the
1308 * /dev nodes. I'm trusting that if hvcs_write gets called and interrupted by
1309 * hvcs_remove (which removes the target device and executes tty_hangup()) that
1310 * tty_hangup will allow hvcs_write time to complete execution before it
1311 * terminates our device.
1312 */
1313static int hvcs_write(struct tty_struct *tty,
1314 const unsigned char *buf, int count)
1315{
1316 struct hvcs_struct *hvcsd = tty->driver_data;
1317 unsigned int unit_address;
1318 const unsigned char *charbuf;
1319 unsigned long flags;
1320 int total_sent = 0;
1321 int tosend = 0;
1322 int result = 0;
1323
1324 /*
1325 * If they don't check the return code off of their open they may
1326 * attempt this even if there is no connected device.
1327 */
1328 if (!hvcsd)
1329 return -ENODEV;
1330
1331 /* Reasonable size to prevent user level flooding */
1332 if (count > HVCS_MAX_FROM_USER) {
1333 printk(KERN_WARNING "HVCS write: count being truncated to"
1334 " HVCS_MAX_FROM_USER.\n");
1335 count = HVCS_MAX_FROM_USER;
1336 }
1337
1338 charbuf = buf;
1339
1340 spin_lock_irqsave(&hvcsd->lock, flags);
1341
1342 /*
1343 * Somehow an open succedded but the device was removed or the
1344 * connection terminated between the vty-server and partner vty during
1345 * the middle of a write operation? This is a crummy place to do this
1346 * but we want to keep it all in the spinlock.
1347 */
1348 if (hvcsd->open_count <= 0) {
1349 spin_unlock_irqrestore(&hvcsd->lock, flags);
1350 return -ENODEV;
1351 }
1352
1353 unit_address = hvcsd->vdev->unit_address;
1354
1355 while (count > 0) {
1356 tosend = min(count, (HVCS_BUFF_LEN - hvcsd->chars_in_buffer));
1357 /*
1358 * No more space, this probably means that the last call to
1359 * hvcs_write() didn't succeed and the buffer was filled up.
1360 */
1361 if (!tosend)
1362 break;
1363
1364 memcpy(&hvcsd->buffer[hvcsd->chars_in_buffer],
1365 &charbuf[total_sent],
1366 tosend);
1367
1368 hvcsd->chars_in_buffer += tosend;
1369
1370 result = 0;
1371
1372 /*
1373 * If this is true then we don't want to try writing to the
1374 * hypervisor because that is the kernel_threads job now. We'll
1375 * just add to the buffer.
1376 */
1377 if (!(hvcsd->todo_mask & HVCS_TRY_WRITE))
1378 /* won't send partial writes */
1379 result = hvc_put_chars(unit_address,
1380 &hvcsd->buffer[0],
1381 hvcsd->chars_in_buffer);
1382
1383 /*
1384 * Since we know we have enough room in hvcsd->buffer for
1385 * tosend we record that it was sent regardless of whether the
1386 * hypervisor actually took it because we have it buffered.
1387 */
1388 total_sent+=tosend;
1389 count-=tosend;
1390 if (result == 0) {
1391 hvcsd->todo_mask |= HVCS_TRY_WRITE;
1392 hvcs_kick();
1393 break;
1394 }
1395
1396 hvcsd->chars_in_buffer = 0;
1397 /*
1398 * Test after the chars_in_buffer reset otherwise this could
1399 * deadlock our writes if hvc_put_chars fails.
1400 */
1401 if (result < 0)
1402 break;
1403 }
1404
1405 spin_unlock_irqrestore(&hvcsd->lock, flags);
1406
1407 if (result == -1)
1408 return -EIO;
1409 else
1410 return total_sent;
1411}
1412
1413/*
1414 * This is really asking how much can we guarentee that we can send or that we
1415 * absolutely WILL BUFFER if we can't send it. This driver MUST honor the
1416 * return value, hence the reason for hvcs_struct buffering.
1417 */
1418static int hvcs_write_room(struct tty_struct *tty)
1419{
1420 struct hvcs_struct *hvcsd = tty->driver_data;
1421
1422 if (!hvcsd || hvcsd->open_count <= 0)
1423 return 0;
1424
1425 return HVCS_BUFF_LEN - hvcsd->chars_in_buffer;
1426}
1427
1428static int hvcs_chars_in_buffer(struct tty_struct *tty)
1429{
1430 struct hvcs_struct *hvcsd = tty->driver_data;
1431
1432 return hvcsd->chars_in_buffer;
1433}
1434
1435static const struct tty_operations hvcs_ops = {
1436 .open = hvcs_open,
1437 .close = hvcs_close,
1438 .hangup = hvcs_hangup,
1439 .write = hvcs_write,
1440 .write_room = hvcs_write_room,
1441 .chars_in_buffer = hvcs_chars_in_buffer,
1442 .unthrottle = hvcs_unthrottle,
1443 .throttle = hvcs_throttle,
1444};
1445
1446static int hvcs_alloc_index_list(int n)
1447{
1448 int i;
1449
1450 hvcs_index_list = kmalloc(n * sizeof(hvcs_index_count),GFP_KERNEL);
1451 if (!hvcs_index_list)
1452 return -ENOMEM;
1453 hvcs_index_count = n;
1454 for (i = 0; i < hvcs_index_count; i++)
1455 hvcs_index_list[i] = -1;
1456 return 0;
1457}
1458
1459static void hvcs_free_index_list(void)
1460{
1461 /* Paranoia check to be thorough. */
1462 kfree(hvcs_index_list);
1463 hvcs_index_list = NULL;
1464 hvcs_index_count = 0;
1465}
1466
1467static int __init hvcs_module_init(void)
1468{
1469 int rc;
1470 int num_ttys_to_alloc;
1471
1472 printk(KERN_INFO "Initializing %s\n", hvcs_driver_string);
1473
1474 /* Has the user specified an overload with an insmod param? */
1475 if (hvcs_parm_num_devs <= 0 ||
1476 (hvcs_parm_num_devs > HVCS_MAX_SERVER_ADAPTERS)) {
1477 num_ttys_to_alloc = HVCS_DEFAULT_SERVER_ADAPTERS;
1478 } else
1479 num_ttys_to_alloc = hvcs_parm_num_devs;
1480
1481 hvcs_tty_driver = alloc_tty_driver(num_ttys_to_alloc);
1482 if (!hvcs_tty_driver)
1483 return -ENOMEM;
1484
1485 if (hvcs_alloc_index_list(num_ttys_to_alloc)) {
1486 rc = -ENOMEM;
1487 goto index_fail;
1488 }
1489
1490 hvcs_tty_driver->owner = THIS_MODULE;
1491
1492 hvcs_tty_driver->driver_name = hvcs_driver_name;
1493 hvcs_tty_driver->name = hvcs_device_node;
1494
1495 /*
1496 * We'll let the system assign us a major number, indicated by leaving
1497 * it blank.
1498 */
1499
1500 hvcs_tty_driver->minor_start = HVCS_MINOR_START;
1501 hvcs_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
1502
1503 /*
1504 * We role our own so that we DONT ECHO. We can't echo because the
1505 * device we are connecting to already echoes by default and this would
1506 * throw us into a horrible recursive echo-echo-echo loop.
1507 */
1508 hvcs_tty_driver->init_termios = hvcs_tty_termios;
1509 hvcs_tty_driver->flags = TTY_DRIVER_REAL_RAW;
1510
1511 tty_set_operations(hvcs_tty_driver, &hvcs_ops);
1512
1513 /*
1514 * The following call will result in sysfs entries that denote the
1515 * dynamically assigned major and minor numbers for our devices.
1516 */
1517 if (tty_register_driver(hvcs_tty_driver)) {
1518 printk(KERN_ERR "HVCS: registration as a tty driver failed.\n");
1519 rc = -EIO;
1520 goto register_fail;
1521 }
1522
1523 hvcs_pi_buff = kmalloc(PAGE_SIZE, GFP_KERNEL);
1524 if (!hvcs_pi_buff) {
1525 rc = -ENOMEM;
1526 goto buff_alloc_fail;
1527 }
1528
1529 hvcs_task = kthread_run(khvcsd, NULL, "khvcsd");
1530 if (IS_ERR(hvcs_task)) {
1531 printk(KERN_ERR "HVCS: khvcsd creation failed. Driver not loaded.\n");
1532 rc = -EIO;
1533 goto kthread_fail;
1534 }
1535
1536 rc = vio_register_driver(&hvcs_vio_driver);
1537 if (rc) {
1538 printk(KERN_ERR "HVCS: can't register vio driver\n");
1539 goto vio_fail;
1540 }
1541
1542 /*
1543 * This needs to be done AFTER the vio_register_driver() call or else
1544 * the kobjects won't be initialized properly.
1545 */
1546 rc = driver_create_file(&(hvcs_vio_driver.driver), &driver_attr_rescan);
1547 if (rc) {
1548 printk(KERN_ERR "HVCS: sysfs attr create failed\n");
1549 goto attr_fail;
1550 }
1551
1552 printk(KERN_INFO "HVCS: driver module inserted.\n");
1553
1554 return 0;
1555
1556attr_fail:
1557 vio_unregister_driver(&hvcs_vio_driver);
1558vio_fail:
1559 kthread_stop(hvcs_task);
1560kthread_fail:
1561 kfree(hvcs_pi_buff);
1562buff_alloc_fail:
1563 tty_unregister_driver(hvcs_tty_driver);
1564register_fail:
1565 hvcs_free_index_list();
1566index_fail:
1567 put_tty_driver(hvcs_tty_driver);
1568 hvcs_tty_driver = NULL;
1569 return rc;
1570}
1571
1572static void __exit hvcs_module_exit(void)
1573{
1574 /*
1575 * This driver receives hvcs_remove callbacks for each device upon
1576 * module removal.
1577 */
1578
1579 /*
1580 * This synchronous operation will wake the khvcsd kthread if it is
1581 * asleep and will return when khvcsd has terminated.
1582 */
1583 kthread_stop(hvcs_task);
1584
1585 spin_lock(&hvcs_pi_lock);
1586 kfree(hvcs_pi_buff);
1587 hvcs_pi_buff = NULL;
1588 spin_unlock(&hvcs_pi_lock);
1589
1590 driver_remove_file(&hvcs_vio_driver.driver, &driver_attr_rescan);
1591
1592 vio_unregister_driver(&hvcs_vio_driver);
1593
1594 tty_unregister_driver(hvcs_tty_driver);
1595
1596 hvcs_free_index_list();
1597
1598 put_tty_driver(hvcs_tty_driver);
1599
1600 printk(KERN_INFO "HVCS: driver module removed.\n");
1601}
1602
1603module_init(hvcs_module_init);
1604module_exit(hvcs_module_exit);
diff --git a/drivers/tty/hvc/hvsi.c b/drivers/tty/hvc/hvsi.c
new file mode 100644
index 000000000000..67a75a502c01
--- /dev/null
+++ b/drivers/tty/hvc/hvsi.c
@@ -0,0 +1,1314 @@
1/*
2 * Copyright (C) 2004 Hollis Blanchard <hollisb@us.ibm.com>, IBM
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 */
18
19/* Host Virtual Serial Interface (HVSI) is a protocol between the hosted OS
20 * and the service processor on IBM pSeries servers. On these servers, there
21 * are no serial ports under the OS's control, and sometimes there is no other
22 * console available either. However, the service processor has two standard
23 * serial ports, so this over-complicated protocol allows the OS to control
24 * those ports by proxy.
25 *
26 * Besides data, the procotol supports the reading/writing of the serial
27 * port's DTR line, and the reading of the CD line. This is to allow the OS to
28 * control a modem attached to the service processor's serial port. Note that
29 * the OS cannot change the speed of the port through this protocol.
30 */
31
32#undef DEBUG
33
34#include <linux/console.h>
35#include <linux/ctype.h>
36#include <linux/delay.h>
37#include <linux/init.h>
38#include <linux/interrupt.h>
39#include <linux/module.h>
40#include <linux/major.h>
41#include <linux/kernel.h>
42#include <linux/spinlock.h>
43#include <linux/sysrq.h>
44#include <linux/tty.h>
45#include <linux/tty_flip.h>
46#include <asm/hvcall.h>
47#include <asm/hvconsole.h>
48#include <asm/prom.h>
49#include <asm/uaccess.h>
50#include <asm/vio.h>
51#include <asm/param.h>
52
53#define HVSI_MAJOR 229
54#define HVSI_MINOR 128
55#define MAX_NR_HVSI_CONSOLES 4
56
57#define HVSI_TIMEOUT (5*HZ)
58#define HVSI_VERSION 1
59#define HVSI_MAX_PACKET 256
60#define HVSI_MAX_READ 16
61#define HVSI_MAX_OUTGOING_DATA 12
62#define N_OUTBUF 12
63
64/*
65 * we pass data via two 8-byte registers, so we would like our char arrays
66 * properly aligned for those loads.
67 */
68#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
69
70struct hvsi_struct {
71 struct delayed_work writer;
72 struct work_struct handshaker;
73 wait_queue_head_t emptyq; /* woken when outbuf is emptied */
74 wait_queue_head_t stateq; /* woken when HVSI state changes */
75 spinlock_t lock;
76 int index;
77 struct tty_struct *tty;
78 int count;
79 uint8_t throttle_buf[128];
80 uint8_t outbuf[N_OUTBUF]; /* to implement write_room and chars_in_buffer */
81 /* inbuf is for packet reassembly. leave a little room for leftovers. */
82 uint8_t inbuf[HVSI_MAX_PACKET + HVSI_MAX_READ];
83 uint8_t *inbuf_end;
84 int n_throttle;
85 int n_outbuf;
86 uint32_t vtermno;
87 uint32_t virq;
88 atomic_t seqno; /* HVSI packet sequence number */
89 uint16_t mctrl;
90 uint8_t state; /* HVSI protocol state */
91 uint8_t flags;
92#ifdef CONFIG_MAGIC_SYSRQ
93 uint8_t sysrq;
94#endif /* CONFIG_MAGIC_SYSRQ */
95};
96static struct hvsi_struct hvsi_ports[MAX_NR_HVSI_CONSOLES];
97
98static struct tty_driver *hvsi_driver;
99static int hvsi_count;
100static int (*hvsi_wait)(struct hvsi_struct *hp, int state);
101
102enum HVSI_PROTOCOL_STATE {
103 HVSI_CLOSED,
104 HVSI_WAIT_FOR_VER_RESPONSE,
105 HVSI_WAIT_FOR_VER_QUERY,
106 HVSI_OPEN,
107 HVSI_WAIT_FOR_MCTRL_RESPONSE,
108 HVSI_FSP_DIED,
109};
110#define HVSI_CONSOLE 0x1
111
112#define VS_DATA_PACKET_HEADER 0xff
113#define VS_CONTROL_PACKET_HEADER 0xfe
114#define VS_QUERY_PACKET_HEADER 0xfd
115#define VS_QUERY_RESPONSE_PACKET_HEADER 0xfc
116
117/* control verbs */
118#define VSV_SET_MODEM_CTL 1 /* to service processor only */
119#define VSV_MODEM_CTL_UPDATE 2 /* from service processor only */
120#define VSV_CLOSE_PROTOCOL 3
121
122/* query verbs */
123#define VSV_SEND_VERSION_NUMBER 1
124#define VSV_SEND_MODEM_CTL_STATUS 2
125
126/* yes, these masks are not consecutive. */
127#define HVSI_TSDTR 0x01
128#define HVSI_TSCD 0x20
129
130struct hvsi_header {
131 uint8_t type;
132 uint8_t len;
133 uint16_t seqno;
134} __attribute__((packed));
135
136struct hvsi_data {
137 uint8_t type;
138 uint8_t len;
139 uint16_t seqno;
140 uint8_t data[HVSI_MAX_OUTGOING_DATA];
141} __attribute__((packed));
142
143struct hvsi_control {
144 uint8_t type;
145 uint8_t len;
146 uint16_t seqno;
147 uint16_t verb;
148 /* optional depending on verb: */
149 uint32_t word;
150 uint32_t mask;
151} __attribute__((packed));
152
153struct hvsi_query {
154 uint8_t type;
155 uint8_t len;
156 uint16_t seqno;
157 uint16_t verb;
158} __attribute__((packed));
159
160struct hvsi_query_response {
161 uint8_t type;
162 uint8_t len;
163 uint16_t seqno;
164 uint16_t verb;
165 uint16_t query_seqno;
166 union {
167 uint8_t version;
168 uint32_t mctrl_word;
169 } u;
170} __attribute__((packed));
171
172
173
174static inline int is_console(struct hvsi_struct *hp)
175{
176 return hp->flags & HVSI_CONSOLE;
177}
178
179static inline int is_open(struct hvsi_struct *hp)
180{
181 /* if we're waiting for an mctrl then we're already open */
182 return (hp->state == HVSI_OPEN)
183 || (hp->state == HVSI_WAIT_FOR_MCTRL_RESPONSE);
184}
185
186static inline void print_state(struct hvsi_struct *hp)
187{
188#ifdef DEBUG
189 static const char *state_names[] = {
190 "HVSI_CLOSED",
191 "HVSI_WAIT_FOR_VER_RESPONSE",
192 "HVSI_WAIT_FOR_VER_QUERY",
193 "HVSI_OPEN",
194 "HVSI_WAIT_FOR_MCTRL_RESPONSE",
195 "HVSI_FSP_DIED",
196 };
197 const char *name = (hp->state < ARRAY_SIZE(state_names))
198 ? state_names[hp->state] : "UNKNOWN";
199
200 pr_debug("hvsi%i: state = %s\n", hp->index, name);
201#endif /* DEBUG */
202}
203
204static inline void __set_state(struct hvsi_struct *hp, int state)
205{
206 hp->state = state;
207 print_state(hp);
208 wake_up_all(&hp->stateq);
209}
210
211static inline void set_state(struct hvsi_struct *hp, int state)
212{
213 unsigned long flags;
214
215 spin_lock_irqsave(&hp->lock, flags);
216 __set_state(hp, state);
217 spin_unlock_irqrestore(&hp->lock, flags);
218}
219
220static inline int len_packet(const uint8_t *packet)
221{
222 return (int)((struct hvsi_header *)packet)->len;
223}
224
225static inline int is_header(const uint8_t *packet)
226{
227 struct hvsi_header *header = (struct hvsi_header *)packet;
228 return header->type >= VS_QUERY_RESPONSE_PACKET_HEADER;
229}
230
231static inline int got_packet(const struct hvsi_struct *hp, uint8_t *packet)
232{
233 if (hp->inbuf_end < packet + sizeof(struct hvsi_header))
234 return 0; /* don't even have the packet header */
235
236 if (hp->inbuf_end < (packet + len_packet(packet)))
237 return 0; /* don't have the rest of the packet */
238
239 return 1;
240}
241
242/* shift remaining bytes in packetbuf down */
243static void compact_inbuf(struct hvsi_struct *hp, uint8_t *read_to)
244{
245 int remaining = (int)(hp->inbuf_end - read_to);
246
247 pr_debug("%s: %i chars remain\n", __func__, remaining);
248
249 if (read_to != hp->inbuf)
250 memmove(hp->inbuf, read_to, remaining);
251
252 hp->inbuf_end = hp->inbuf + remaining;
253}
254
255#ifdef DEBUG
256#define dbg_dump_packet(packet) dump_packet(packet)
257#define dbg_dump_hex(data, len) dump_hex(data, len)
258#else
259#define dbg_dump_packet(packet) do { } while (0)
260#define dbg_dump_hex(data, len) do { } while (0)
261#endif
262
263static void dump_hex(const uint8_t *data, int len)
264{
265 int i;
266
267 printk(" ");
268 for (i=0; i < len; i++)
269 printk("%.2x", data[i]);
270
271 printk("\n ");
272 for (i=0; i < len; i++) {
273 if (isprint(data[i]))
274 printk("%c", data[i]);
275 else
276 printk(".");
277 }
278 printk("\n");
279}
280
281static void dump_packet(uint8_t *packet)
282{
283 struct hvsi_header *header = (struct hvsi_header *)packet;
284
285 printk("type 0x%x, len %i, seqno %i:\n", header->type, header->len,
286 header->seqno);
287
288 dump_hex(packet, header->len);
289}
290
291static int hvsi_read(struct hvsi_struct *hp, char *buf, int count)
292{
293 unsigned long got;
294
295 got = hvc_get_chars(hp->vtermno, buf, count);
296
297 return got;
298}
299
300static void hvsi_recv_control(struct hvsi_struct *hp, uint8_t *packet,
301 struct tty_struct **to_hangup, struct hvsi_struct **to_handshake)
302{
303 struct hvsi_control *header = (struct hvsi_control *)packet;
304
305 switch (header->verb) {
306 case VSV_MODEM_CTL_UPDATE:
307 if ((header->word & HVSI_TSCD) == 0) {
308 /* CD went away; no more connection */
309 pr_debug("hvsi%i: CD dropped\n", hp->index);
310 hp->mctrl &= TIOCM_CD;
311 /* If userland hasn't done an open(2) yet, hp->tty is NULL. */
312 if (hp->tty && !(hp->tty->flags & CLOCAL))
313 *to_hangup = hp->tty;
314 }
315 break;
316 case VSV_CLOSE_PROTOCOL:
317 pr_debug("hvsi%i: service processor came back\n", hp->index);
318 if (hp->state != HVSI_CLOSED) {
319 *to_handshake = hp;
320 }
321 break;
322 default:
323 printk(KERN_WARNING "hvsi%i: unknown HVSI control packet: ",
324 hp->index);
325 dump_packet(packet);
326 break;
327 }
328}
329
330static void hvsi_recv_response(struct hvsi_struct *hp, uint8_t *packet)
331{
332 struct hvsi_query_response *resp = (struct hvsi_query_response *)packet;
333
334 switch (hp->state) {
335 case HVSI_WAIT_FOR_VER_RESPONSE:
336 __set_state(hp, HVSI_WAIT_FOR_VER_QUERY);
337 break;
338 case HVSI_WAIT_FOR_MCTRL_RESPONSE:
339 hp->mctrl = 0;
340 if (resp->u.mctrl_word & HVSI_TSDTR)
341 hp->mctrl |= TIOCM_DTR;
342 if (resp->u.mctrl_word & HVSI_TSCD)
343 hp->mctrl |= TIOCM_CD;
344 __set_state(hp, HVSI_OPEN);
345 break;
346 default:
347 printk(KERN_ERR "hvsi%i: unexpected query response: ", hp->index);
348 dump_packet(packet);
349 break;
350 }
351}
352
353/* respond to service processor's version query */
354static int hvsi_version_respond(struct hvsi_struct *hp, uint16_t query_seqno)
355{
356 struct hvsi_query_response packet __ALIGNED__;
357 int wrote;
358
359 packet.type = VS_QUERY_RESPONSE_PACKET_HEADER;
360 packet.len = sizeof(struct hvsi_query_response);
361 packet.seqno = atomic_inc_return(&hp->seqno);
362 packet.verb = VSV_SEND_VERSION_NUMBER;
363 packet.u.version = HVSI_VERSION;
364 packet.query_seqno = query_seqno+1;
365
366 pr_debug("%s: sending %i bytes\n", __func__, packet.len);
367 dbg_dump_hex((uint8_t*)&packet, packet.len);
368
369 wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
370 if (wrote != packet.len) {
371 printk(KERN_ERR "hvsi%i: couldn't send query response!\n",
372 hp->index);
373 return -EIO;
374 }
375
376 return 0;
377}
378
379static void hvsi_recv_query(struct hvsi_struct *hp, uint8_t *packet)
380{
381 struct hvsi_query *query = (struct hvsi_query *)packet;
382
383 switch (hp->state) {
384 case HVSI_WAIT_FOR_VER_QUERY:
385 hvsi_version_respond(hp, query->seqno);
386 __set_state(hp, HVSI_OPEN);
387 break;
388 default:
389 printk(KERN_ERR "hvsi%i: unexpected query: ", hp->index);
390 dump_packet(packet);
391 break;
392 }
393}
394
395static void hvsi_insert_chars(struct hvsi_struct *hp, const char *buf, int len)
396{
397 int i;
398
399 for (i=0; i < len; i++) {
400 char c = buf[i];
401#ifdef CONFIG_MAGIC_SYSRQ
402 if (c == '\0') {
403 hp->sysrq = 1;
404 continue;
405 } else if (hp->sysrq) {
406 handle_sysrq(c);
407 hp->sysrq = 0;
408 continue;
409 }
410#endif /* CONFIG_MAGIC_SYSRQ */
411 tty_insert_flip_char(hp->tty, c, 0);
412 }
413}
414
415/*
416 * We could get 252 bytes of data at once here. But the tty layer only
417 * throttles us at TTY_THRESHOLD_THROTTLE (128) bytes, so we could overflow
418 * it. Accordingly we won't send more than 128 bytes at a time to the flip
419 * buffer, which will give the tty buffer a chance to throttle us. Should the
420 * value of TTY_THRESHOLD_THROTTLE change in n_tty.c, this code should be
421 * revisited.
422 */
423#define TTY_THRESHOLD_THROTTLE 128
424static struct tty_struct *hvsi_recv_data(struct hvsi_struct *hp,
425 const uint8_t *packet)
426{
427 const struct hvsi_header *header = (const struct hvsi_header *)packet;
428 const uint8_t *data = packet + sizeof(struct hvsi_header);
429 int datalen = header->len - sizeof(struct hvsi_header);
430 int overflow = datalen - TTY_THRESHOLD_THROTTLE;
431
432 pr_debug("queueing %i chars '%.*s'\n", datalen, datalen, data);
433
434 if (datalen == 0)
435 return NULL;
436
437 if (overflow > 0) {
438 pr_debug("%s: got >TTY_THRESHOLD_THROTTLE bytes\n", __func__);
439 datalen = TTY_THRESHOLD_THROTTLE;
440 }
441
442 hvsi_insert_chars(hp, data, datalen);
443
444 if (overflow > 0) {
445 /*
446 * we still have more data to deliver, so we need to save off the
447 * overflow and send it later
448 */
449 pr_debug("%s: deferring overflow\n", __func__);
450 memcpy(hp->throttle_buf, data + TTY_THRESHOLD_THROTTLE, overflow);
451 hp->n_throttle = overflow;
452 }
453
454 return hp->tty;
455}
456
457/*
458 * Returns true/false indicating data successfully read from hypervisor.
459 * Used both to get packets for tty connections and to advance the state
460 * machine during console handshaking (in which case tty = NULL and we ignore
461 * incoming data).
462 */
463static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
464 struct tty_struct **hangup, struct hvsi_struct **handshake)
465{
466 uint8_t *packet = hp->inbuf;
467 int chunklen;
468
469 *flip = NULL;
470 *hangup = NULL;
471 *handshake = NULL;
472
473 chunklen = hvsi_read(hp, hp->inbuf_end, HVSI_MAX_READ);
474 if (chunklen == 0) {
475 pr_debug("%s: 0-length read\n", __func__);
476 return 0;
477 }
478
479 pr_debug("%s: got %i bytes\n", __func__, chunklen);
480 dbg_dump_hex(hp->inbuf_end, chunklen);
481
482 hp->inbuf_end += chunklen;
483
484 /* handle all completed packets */
485 while ((packet < hp->inbuf_end) && got_packet(hp, packet)) {
486 struct hvsi_header *header = (struct hvsi_header *)packet;
487
488 if (!is_header(packet)) {
489 printk(KERN_ERR "hvsi%i: got malformed packet\n", hp->index);
490 /* skip bytes until we find a header or run out of data */
491 while ((packet < hp->inbuf_end) && (!is_header(packet)))
492 packet++;
493 continue;
494 }
495
496 pr_debug("%s: handling %i-byte packet\n", __func__,
497 len_packet(packet));
498 dbg_dump_packet(packet);
499
500 switch (header->type) {
501 case VS_DATA_PACKET_HEADER:
502 if (!is_open(hp))
503 break;
504 if (hp->tty == NULL)
505 break; /* no tty buffer to put data in */
506 *flip = hvsi_recv_data(hp, packet);
507 break;
508 case VS_CONTROL_PACKET_HEADER:
509 hvsi_recv_control(hp, packet, hangup, handshake);
510 break;
511 case VS_QUERY_RESPONSE_PACKET_HEADER:
512 hvsi_recv_response(hp, packet);
513 break;
514 case VS_QUERY_PACKET_HEADER:
515 hvsi_recv_query(hp, packet);
516 break;
517 default:
518 printk(KERN_ERR "hvsi%i: unknown HVSI packet type 0x%x\n",
519 hp->index, header->type);
520 dump_packet(packet);
521 break;
522 }
523
524 packet += len_packet(packet);
525
526 if (*hangup || *handshake) {
527 pr_debug("%s: hangup or handshake\n", __func__);
528 /*
529 * we need to send the hangup now before receiving any more data.
530 * If we get "data, hangup, data", we can't deliver the second
531 * data before the hangup.
532 */
533 break;
534 }
535 }
536
537 compact_inbuf(hp, packet);
538
539 return 1;
540}
541
542static void hvsi_send_overflow(struct hvsi_struct *hp)
543{
544 pr_debug("%s: delivering %i bytes overflow\n", __func__,
545 hp->n_throttle);
546
547 hvsi_insert_chars(hp, hp->throttle_buf, hp->n_throttle);
548 hp->n_throttle = 0;
549}
550
551/*
552 * must get all pending data because we only get an irq on empty->non-empty
553 * transition
554 */
555static irqreturn_t hvsi_interrupt(int irq, void *arg)
556{
557 struct hvsi_struct *hp = (struct hvsi_struct *)arg;
558 struct tty_struct *flip;
559 struct tty_struct *hangup;
560 struct hvsi_struct *handshake;
561 unsigned long flags;
562 int again = 1;
563
564 pr_debug("%s\n", __func__);
565
566 while (again) {
567 spin_lock_irqsave(&hp->lock, flags);
568 again = hvsi_load_chunk(hp, &flip, &hangup, &handshake);
569 spin_unlock_irqrestore(&hp->lock, flags);
570
571 /*
572 * we have to call tty_flip_buffer_push() and tty_hangup() outside our
573 * spinlock. But we also have to keep going until we've read all the
574 * available data.
575 */
576
577 if (flip) {
578 /* there was data put in the tty flip buffer */
579 tty_flip_buffer_push(flip);
580 flip = NULL;
581 }
582
583 if (hangup) {
584 tty_hangup(hangup);
585 }
586
587 if (handshake) {
588 pr_debug("hvsi%i: attempting re-handshake\n", handshake->index);
589 schedule_work(&handshake->handshaker);
590 }
591 }
592
593 spin_lock_irqsave(&hp->lock, flags);
594 if (hp->tty && hp->n_throttle
595 && (!test_bit(TTY_THROTTLED, &hp->tty->flags))) {
596 /* we weren't hung up and we weren't throttled, so we can deliver the
597 * rest now */
598 flip = hp->tty;
599 hvsi_send_overflow(hp);
600 }
601 spin_unlock_irqrestore(&hp->lock, flags);
602
603 if (flip) {
604 tty_flip_buffer_push(flip);
605 }
606
607 return IRQ_HANDLED;
608}
609
610/* for boot console, before the irq handler is running */
611static int __init poll_for_state(struct hvsi_struct *hp, int state)
612{
613 unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
614
615 for (;;) {
616 hvsi_interrupt(hp->virq, (void *)hp); /* get pending data */
617
618 if (hp->state == state)
619 return 0;
620
621 mdelay(5);
622 if (time_after(jiffies, end_jiffies))
623 return -EIO;
624 }
625}
626
627/* wait for irq handler to change our state */
628static int wait_for_state(struct hvsi_struct *hp, int state)
629{
630 int ret = 0;
631
632 if (!wait_event_timeout(hp->stateq, (hp->state == state), HVSI_TIMEOUT))
633 ret = -EIO;
634
635 return ret;
636}
637
638static int hvsi_query(struct hvsi_struct *hp, uint16_t verb)
639{
640 struct hvsi_query packet __ALIGNED__;
641 int wrote;
642
643 packet.type = VS_QUERY_PACKET_HEADER;
644 packet.len = sizeof(struct hvsi_query);
645 packet.seqno = atomic_inc_return(&hp->seqno);
646 packet.verb = verb;
647
648 pr_debug("%s: sending %i bytes\n", __func__, packet.len);
649 dbg_dump_hex((uint8_t*)&packet, packet.len);
650
651 wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
652 if (wrote != packet.len) {
653 printk(KERN_ERR "hvsi%i: couldn't send query (%i)!\n", hp->index,
654 wrote);
655 return -EIO;
656 }
657
658 return 0;
659}
660
661static int hvsi_get_mctrl(struct hvsi_struct *hp)
662{
663 int ret;
664
665 set_state(hp, HVSI_WAIT_FOR_MCTRL_RESPONSE);
666 hvsi_query(hp, VSV_SEND_MODEM_CTL_STATUS);
667
668 ret = hvsi_wait(hp, HVSI_OPEN);
669 if (ret < 0) {
670 printk(KERN_ERR "hvsi%i: didn't get modem flags\n", hp->index);
671 set_state(hp, HVSI_OPEN);
672 return ret;
673 }
674
675 pr_debug("%s: mctrl 0x%x\n", __func__, hp->mctrl);
676
677 return 0;
678}
679
680/* note that we can only set DTR */
681static int hvsi_set_mctrl(struct hvsi_struct *hp, uint16_t mctrl)
682{
683 struct hvsi_control packet __ALIGNED__;
684 int wrote;
685
686 packet.type = VS_CONTROL_PACKET_HEADER,
687 packet.seqno = atomic_inc_return(&hp->seqno);
688 packet.len = sizeof(struct hvsi_control);
689 packet.verb = VSV_SET_MODEM_CTL;
690 packet.mask = HVSI_TSDTR;
691
692 if (mctrl & TIOCM_DTR)
693 packet.word = HVSI_TSDTR;
694
695 pr_debug("%s: sending %i bytes\n", __func__, packet.len);
696 dbg_dump_hex((uint8_t*)&packet, packet.len);
697
698 wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
699 if (wrote != packet.len) {
700 printk(KERN_ERR "hvsi%i: couldn't set DTR!\n", hp->index);
701 return -EIO;
702 }
703
704 return 0;
705}
706
707static void hvsi_drain_input(struct hvsi_struct *hp)
708{
709 uint8_t buf[HVSI_MAX_READ] __ALIGNED__;
710 unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
711
712 while (time_before(end_jiffies, jiffies))
713 if (0 == hvsi_read(hp, buf, HVSI_MAX_READ))
714 break;
715}
716
717static int hvsi_handshake(struct hvsi_struct *hp)
718{
719 int ret;
720
721 /*
722 * We could have a CLOSE or other data waiting for us before we even try
723 * to open; try to throw it all away so we don't get confused. (CLOSE
724 * is the first message sent up the pipe when the FSP comes online. We
725 * need to distinguish between "it came up a while ago and we're the first
726 * user" and "it was just reset before it saw our handshake packet".)
727 */
728 hvsi_drain_input(hp);
729
730 set_state(hp, HVSI_WAIT_FOR_VER_RESPONSE);
731 ret = hvsi_query(hp, VSV_SEND_VERSION_NUMBER);
732 if (ret < 0) {
733 printk(KERN_ERR "hvsi%i: couldn't send version query\n", hp->index);
734 return ret;
735 }
736
737 ret = hvsi_wait(hp, HVSI_OPEN);
738 if (ret < 0)
739 return ret;
740
741 return 0;
742}
743
744static void hvsi_handshaker(struct work_struct *work)
745{
746 struct hvsi_struct *hp =
747 container_of(work, struct hvsi_struct, handshaker);
748
749 if (hvsi_handshake(hp) >= 0)
750 return;
751
752 printk(KERN_ERR "hvsi%i: re-handshaking failed\n", hp->index);
753 if (is_console(hp)) {
754 /*
755 * ttys will re-attempt the handshake via hvsi_open, but
756 * the console will not.
757 */
758 printk(KERN_ERR "hvsi%i: lost console!\n", hp->index);
759 }
760}
761
762static int hvsi_put_chars(struct hvsi_struct *hp, const char *buf, int count)
763{
764 struct hvsi_data packet __ALIGNED__;
765 int ret;
766
767 BUG_ON(count > HVSI_MAX_OUTGOING_DATA);
768
769 packet.type = VS_DATA_PACKET_HEADER;
770 packet.seqno = atomic_inc_return(&hp->seqno);
771 packet.len = count + sizeof(struct hvsi_header);
772 memcpy(&packet.data, buf, count);
773
774 ret = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
775 if (ret == packet.len) {
776 /* return the number of chars written, not the packet length */
777 return count;
778 }
779 return ret; /* return any errors */
780}
781
782static void hvsi_close_protocol(struct hvsi_struct *hp)
783{
784 struct hvsi_control packet __ALIGNED__;
785
786 packet.type = VS_CONTROL_PACKET_HEADER;
787 packet.seqno = atomic_inc_return(&hp->seqno);
788 packet.len = 6;
789 packet.verb = VSV_CLOSE_PROTOCOL;
790
791 pr_debug("%s: sending %i bytes\n", __func__, packet.len);
792 dbg_dump_hex((uint8_t*)&packet, packet.len);
793
794 hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
795}
796
797static int hvsi_open(struct tty_struct *tty, struct file *filp)
798{
799 struct hvsi_struct *hp;
800 unsigned long flags;
801 int line = tty->index;
802 int ret;
803
804 pr_debug("%s\n", __func__);
805
806 if (line < 0 || line >= hvsi_count)
807 return -ENODEV;
808 hp = &hvsi_ports[line];
809
810 tty->driver_data = hp;
811
812 mb();
813 if (hp->state == HVSI_FSP_DIED)
814 return -EIO;
815
816 spin_lock_irqsave(&hp->lock, flags);
817 hp->tty = tty;
818 hp->count++;
819 atomic_set(&hp->seqno, 0);
820 h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
821 spin_unlock_irqrestore(&hp->lock, flags);
822
823 if (is_console(hp))
824 return 0; /* this has already been handshaked as the console */
825
826 ret = hvsi_handshake(hp);
827 if (ret < 0) {
828 printk(KERN_ERR "%s: HVSI handshaking failed\n", tty->name);
829 return ret;
830 }
831
832 ret = hvsi_get_mctrl(hp);
833 if (ret < 0) {
834 printk(KERN_ERR "%s: couldn't get initial modem flags\n", tty->name);
835 return ret;
836 }
837
838 ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
839 if (ret < 0) {
840 printk(KERN_ERR "%s: couldn't set DTR\n", tty->name);
841 return ret;
842 }
843
844 return 0;
845}
846
847/* wait for hvsi_write_worker to empty hp->outbuf */
848static void hvsi_flush_output(struct hvsi_struct *hp)
849{
850 wait_event_timeout(hp->emptyq, (hp->n_outbuf <= 0), HVSI_TIMEOUT);
851
852 /* 'writer' could still be pending if it didn't see n_outbuf = 0 yet */
853 cancel_delayed_work_sync(&hp->writer);
854 flush_work_sync(&hp->handshaker);
855
856 /*
857 * it's also possible that our timeout expired and hvsi_write_worker
858 * didn't manage to push outbuf. poof.
859 */
860 hp->n_outbuf = 0;
861}
862
863static void hvsi_close(struct tty_struct *tty, struct file *filp)
864{
865 struct hvsi_struct *hp = tty->driver_data;
866 unsigned long flags;
867
868 pr_debug("%s\n", __func__);
869
870 if (tty_hung_up_p(filp))
871 return;
872
873 spin_lock_irqsave(&hp->lock, flags);
874
875 if (--hp->count == 0) {
876 hp->tty = NULL;
877 hp->inbuf_end = hp->inbuf; /* discard remaining partial packets */
878
879 /* only close down connection if it is not the console */
880 if (!is_console(hp)) {
881 h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE); /* no more irqs */
882 __set_state(hp, HVSI_CLOSED);
883 /*
884 * any data delivered to the tty layer after this will be
885 * discarded (except for XON/XOFF)
886 */
887 tty->closing = 1;
888
889 spin_unlock_irqrestore(&hp->lock, flags);
890
891 /* let any existing irq handlers finish. no more will start. */
892 synchronize_irq(hp->virq);
893
894 /* hvsi_write_worker will re-schedule until outbuf is empty. */
895 hvsi_flush_output(hp);
896
897 /* tell FSP to stop sending data */
898 hvsi_close_protocol(hp);
899
900 /*
901 * drain anything FSP is still in the middle of sending, and let
902 * hvsi_handshake drain the rest on the next open.
903 */
904 hvsi_drain_input(hp);
905
906 spin_lock_irqsave(&hp->lock, flags);
907 }
908 } else if (hp->count < 0)
909 printk(KERN_ERR "hvsi_close %lu: oops, count is %d\n",
910 hp - hvsi_ports, hp->count);
911
912 spin_unlock_irqrestore(&hp->lock, flags);
913}
914
915static void hvsi_hangup(struct tty_struct *tty)
916{
917 struct hvsi_struct *hp = tty->driver_data;
918 unsigned long flags;
919
920 pr_debug("%s\n", __func__);
921
922 spin_lock_irqsave(&hp->lock, flags);
923
924 hp->count = 0;
925 hp->n_outbuf = 0;
926 hp->tty = NULL;
927
928 spin_unlock_irqrestore(&hp->lock, flags);
929}
930
931/* called with hp->lock held */
932static void hvsi_push(struct hvsi_struct *hp)
933{
934 int n;
935
936 if (hp->n_outbuf <= 0)
937 return;
938
939 n = hvsi_put_chars(hp, hp->outbuf, hp->n_outbuf);
940 if (n > 0) {
941 /* success */
942 pr_debug("%s: wrote %i chars\n", __func__, n);
943 hp->n_outbuf = 0;
944 } else if (n == -EIO) {
945 __set_state(hp, HVSI_FSP_DIED);
946 printk(KERN_ERR "hvsi%i: service processor died\n", hp->index);
947 }
948}
949
950/* hvsi_write_worker will keep rescheduling itself until outbuf is empty */
951static void hvsi_write_worker(struct work_struct *work)
952{
953 struct hvsi_struct *hp =
954 container_of(work, struct hvsi_struct, writer.work);
955 unsigned long flags;
956#ifdef DEBUG
957 static long start_j = 0;
958
959 if (start_j == 0)
960 start_j = jiffies;
961#endif /* DEBUG */
962
963 spin_lock_irqsave(&hp->lock, flags);
964
965 pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
966
967 if (!is_open(hp)) {
968 /*
969 * We could have a non-open connection if the service processor died
970 * while we were busily scheduling ourselves. In that case, it could
971 * be minutes before the service processor comes back, so only try
972 * again once a second.
973 */
974 schedule_delayed_work(&hp->writer, HZ);
975 goto out;
976 }
977
978 hvsi_push(hp);
979 if (hp->n_outbuf > 0)
980 schedule_delayed_work(&hp->writer, 10);
981 else {
982#ifdef DEBUG
983 pr_debug("%s: outbuf emptied after %li jiffies\n", __func__,
984 jiffies - start_j);
985 start_j = 0;
986#endif /* DEBUG */
987 wake_up_all(&hp->emptyq);
988 tty_wakeup(hp->tty);
989 }
990
991out:
992 spin_unlock_irqrestore(&hp->lock, flags);
993}
994
995static int hvsi_write_room(struct tty_struct *tty)
996{
997 struct hvsi_struct *hp = tty->driver_data;
998
999 return N_OUTBUF - hp->n_outbuf;
1000}
1001
1002static int hvsi_chars_in_buffer(struct tty_struct *tty)
1003{
1004 struct hvsi_struct *hp = tty->driver_data;
1005
1006 return hp->n_outbuf;
1007}
1008
1009static int hvsi_write(struct tty_struct *tty,
1010 const unsigned char *buf, int count)
1011{
1012 struct hvsi_struct *hp = tty->driver_data;
1013 const char *source = buf;
1014 unsigned long flags;
1015 int total = 0;
1016 int origcount = count;
1017
1018 spin_lock_irqsave(&hp->lock, flags);
1019
1020 pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
1021
1022 if (!is_open(hp)) {
1023 /* we're either closing or not yet open; don't accept data */
1024 pr_debug("%s: not open\n", __func__);
1025 goto out;
1026 }
1027
1028 /*
1029 * when the hypervisor buffer (16K) fills, data will stay in hp->outbuf
1030 * and hvsi_write_worker will be scheduled. subsequent hvsi_write() calls
1031 * will see there is no room in outbuf and return.
1032 */
1033 while ((count > 0) && (hvsi_write_room(hp->tty) > 0)) {
1034 int chunksize = min(count, hvsi_write_room(hp->tty));
1035
1036 BUG_ON(hp->n_outbuf < 0);
1037 memcpy(hp->outbuf + hp->n_outbuf, source, chunksize);
1038 hp->n_outbuf += chunksize;
1039
1040 total += chunksize;
1041 source += chunksize;
1042 count -= chunksize;
1043 hvsi_push(hp);
1044 }
1045
1046 if (hp->n_outbuf > 0) {
1047 /*
1048 * we weren't able to write it all to the hypervisor.
1049 * schedule another push attempt.
1050 */
1051 schedule_delayed_work(&hp->writer, 10);
1052 }
1053
1054out:
1055 spin_unlock_irqrestore(&hp->lock, flags);
1056
1057 if (total != origcount)
1058 pr_debug("%s: wanted %i, only wrote %i\n", __func__, origcount,
1059 total);
1060
1061 return total;
1062}
1063
1064/*
1065 * I have never seen throttle or unthrottle called, so this little throttle
1066 * buffering scheme may or may not work.
1067 */
1068static void hvsi_throttle(struct tty_struct *tty)
1069{
1070 struct hvsi_struct *hp = tty->driver_data;
1071
1072 pr_debug("%s\n", __func__);
1073
1074 h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE);
1075}
1076
1077static void hvsi_unthrottle(struct tty_struct *tty)
1078{
1079 struct hvsi_struct *hp = tty->driver_data;
1080 unsigned long flags;
1081 int shouldflip = 0;
1082
1083 pr_debug("%s\n", __func__);
1084
1085 spin_lock_irqsave(&hp->lock, flags);
1086 if (hp->n_throttle) {
1087 hvsi_send_overflow(hp);
1088 shouldflip = 1;
1089 }
1090 spin_unlock_irqrestore(&hp->lock, flags);
1091
1092 if (shouldflip)
1093 tty_flip_buffer_push(hp->tty);
1094
1095 h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
1096}
1097
1098static int hvsi_tiocmget(struct tty_struct *tty, struct file *file)
1099{
1100 struct hvsi_struct *hp = tty->driver_data;
1101
1102 hvsi_get_mctrl(hp);
1103 return hp->mctrl;
1104}
1105
1106static int hvsi_tiocmset(struct tty_struct *tty, struct file *file,
1107 unsigned int set, unsigned int clear)
1108{
1109 struct hvsi_struct *hp = tty->driver_data;
1110 unsigned long flags;
1111 uint16_t new_mctrl;
1112
1113 /* we can only alter DTR */
1114 clear &= TIOCM_DTR;
1115 set &= TIOCM_DTR;
1116
1117 spin_lock_irqsave(&hp->lock, flags);
1118
1119 new_mctrl = (hp->mctrl & ~clear) | set;
1120
1121 if (hp->mctrl != new_mctrl) {
1122 hvsi_set_mctrl(hp, new_mctrl);
1123 hp->mctrl = new_mctrl;
1124 }
1125 spin_unlock_irqrestore(&hp->lock, flags);
1126
1127 return 0;
1128}
1129
1130
1131static const struct tty_operations hvsi_ops = {
1132 .open = hvsi_open,
1133 .close = hvsi_close,
1134 .write = hvsi_write,
1135 .hangup = hvsi_hangup,
1136 .write_room = hvsi_write_room,
1137 .chars_in_buffer = hvsi_chars_in_buffer,
1138 .throttle = hvsi_throttle,
1139 .unthrottle = hvsi_unthrottle,
1140 .tiocmget = hvsi_tiocmget,
1141 .tiocmset = hvsi_tiocmset,
1142};
1143
1144static int __init hvsi_init(void)
1145{
1146 int i;
1147
1148 hvsi_driver = alloc_tty_driver(hvsi_count);
1149 if (!hvsi_driver)
1150 return -ENOMEM;
1151
1152 hvsi_driver->owner = THIS_MODULE;
1153 hvsi_driver->driver_name = "hvsi";
1154 hvsi_driver->name = "hvsi";
1155 hvsi_driver->major = HVSI_MAJOR;
1156 hvsi_driver->minor_start = HVSI_MINOR;
1157 hvsi_driver->type = TTY_DRIVER_TYPE_SYSTEM;
1158 hvsi_driver->init_termios = tty_std_termios;
1159 hvsi_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
1160 hvsi_driver->init_termios.c_ispeed = 9600;
1161 hvsi_driver->init_termios.c_ospeed = 9600;
1162 hvsi_driver->flags = TTY_DRIVER_REAL_RAW;
1163 tty_set_operations(hvsi_driver, &hvsi_ops);
1164
1165 for (i=0; i < hvsi_count; i++) {
1166 struct hvsi_struct *hp = &hvsi_ports[i];
1167 int ret = 1;
1168
1169 ret = request_irq(hp->virq, hvsi_interrupt, IRQF_DISABLED, "hvsi", hp);
1170 if (ret)
1171 printk(KERN_ERR "HVSI: couldn't reserve irq 0x%x (error %i)\n",
1172 hp->virq, ret);
1173 }
1174 hvsi_wait = wait_for_state; /* irqs active now */
1175
1176 if (tty_register_driver(hvsi_driver))
1177 panic("Couldn't register hvsi console driver\n");
1178
1179 printk(KERN_DEBUG "HVSI: registered %i devices\n", hvsi_count);
1180
1181 return 0;
1182}
1183device_initcall(hvsi_init);
1184
1185/***** console (not tty) code: *****/
1186
1187static void hvsi_console_print(struct console *console, const char *buf,
1188 unsigned int count)
1189{
1190 struct hvsi_struct *hp = &hvsi_ports[console->index];
1191 char c[HVSI_MAX_OUTGOING_DATA] __ALIGNED__;
1192 unsigned int i = 0, n = 0;
1193 int ret, donecr = 0;
1194
1195 mb();
1196 if (!is_open(hp))
1197 return;
1198
1199 /*
1200 * ugh, we have to translate LF -> CRLF ourselves, in place.
1201 * copied from hvc_console.c:
1202 */
1203 while (count > 0 || i > 0) {
1204 if (count > 0 && i < sizeof(c)) {
1205 if (buf[n] == '\n' && !donecr) {
1206 c[i++] = '\r';
1207 donecr = 1;
1208 } else {
1209 c[i++] = buf[n++];
1210 donecr = 0;
1211 --count;
1212 }
1213 } else {
1214 ret = hvsi_put_chars(hp, c, i);
1215 if (ret < 0)
1216 i = 0;
1217 i -= ret;
1218 }
1219 }
1220}
1221
1222static struct tty_driver *hvsi_console_device(struct console *console,
1223 int *index)
1224{
1225 *index = console->index;
1226 return hvsi_driver;
1227}
1228
1229static int __init hvsi_console_setup(struct console *console, char *options)
1230{
1231 struct hvsi_struct *hp;
1232 int ret;
1233
1234 if (console->index < 0 || console->index >= hvsi_count)
1235 return -1;
1236 hp = &hvsi_ports[console->index];
1237
1238 /* give the FSP a chance to change the baud rate when we re-open */
1239 hvsi_close_protocol(hp);
1240
1241 ret = hvsi_handshake(hp);
1242 if (ret < 0)
1243 return ret;
1244
1245 ret = hvsi_get_mctrl(hp);
1246 if (ret < 0)
1247 return ret;
1248
1249 ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
1250 if (ret < 0)
1251 return ret;
1252
1253 hp->flags |= HVSI_CONSOLE;
1254
1255 return 0;
1256}
1257
1258static struct console hvsi_console = {
1259 .name = "hvsi",
1260 .write = hvsi_console_print,
1261 .device = hvsi_console_device,
1262 .setup = hvsi_console_setup,
1263 .flags = CON_PRINTBUFFER,
1264 .index = -1,
1265};
1266
1267static int __init hvsi_console_init(void)
1268{
1269 struct device_node *vty;
1270
1271 hvsi_wait = poll_for_state; /* no irqs yet; must poll */
1272
1273 /* search device tree for vty nodes */
1274 for (vty = of_find_compatible_node(NULL, "serial", "hvterm-protocol");
1275 vty != NULL;
1276 vty = of_find_compatible_node(vty, "serial", "hvterm-protocol")) {
1277 struct hvsi_struct *hp;
1278 const uint32_t *vtermno, *irq;
1279
1280 vtermno = of_get_property(vty, "reg", NULL);
1281 irq = of_get_property(vty, "interrupts", NULL);
1282 if (!vtermno || !irq)
1283 continue;
1284
1285 if (hvsi_count >= MAX_NR_HVSI_CONSOLES) {
1286 of_node_put(vty);
1287 break;
1288 }
1289
1290 hp = &hvsi_ports[hvsi_count];
1291 INIT_DELAYED_WORK(&hp->writer, hvsi_write_worker);
1292 INIT_WORK(&hp->handshaker, hvsi_handshaker);
1293 init_waitqueue_head(&hp->emptyq);
1294 init_waitqueue_head(&hp->stateq);
1295 spin_lock_init(&hp->lock);
1296 hp->index = hvsi_count;
1297 hp->inbuf_end = hp->inbuf;
1298 hp->state = HVSI_CLOSED;
1299 hp->vtermno = *vtermno;
1300 hp->virq = irq_create_mapping(NULL, irq[0]);
1301 if (hp->virq == NO_IRQ) {
1302 printk(KERN_ERR "%s: couldn't create irq mapping for 0x%x\n",
1303 __func__, irq[0]);
1304 continue;
1305 }
1306
1307 hvsi_count++;
1308 }
1309
1310 if (hvsi_count)
1311 register_console(&hvsi_console);
1312 return 0;
1313}
1314console_initcall(hvsi_console_init);
diff --git a/drivers/tty/hvc/virtio_console.c b/drivers/tty/hvc/virtio_console.c
new file mode 100644
index 000000000000..896a2ced1d27
--- /dev/null
+++ b/drivers/tty/hvc/virtio_console.c
@@ -0,0 +1,1838 @@
1/*
2 * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
3 * Copyright (C) 2009, 2010 Red Hat, Inc.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19#include <linux/cdev.h>
20#include <linux/debugfs.h>
21#include <linux/device.h>
22#include <linux/err.h>
23#include <linux/fs.h>
24#include <linux/init.h>
25#include <linux/list.h>
26#include <linux/poll.h>
27#include <linux/sched.h>
28#include <linux/slab.h>
29#include <linux/spinlock.h>
30#include <linux/virtio.h>
31#include <linux/virtio_console.h>
32#include <linux/wait.h>
33#include <linux/workqueue.h>
34#include "hvc_console.h"
35
36/*
37 * This is a global struct for storing common data for all the devices
38 * this driver handles.
39 *
40 * Mainly, it has a linked list for all the consoles in one place so
41 * that callbacks from hvc for get_chars(), put_chars() work properly
42 * across multiple devices and multiple ports per device.
43 */
44struct ports_driver_data {
45 /* Used for registering chardevs */
46 struct class *class;
47
48 /* Used for exporting per-port information to debugfs */
49 struct dentry *debugfs_dir;
50
51 /* List of all the devices we're handling */
52 struct list_head portdevs;
53
54 /* Number of devices this driver is handling */
55 unsigned int index;
56
57 /*
58 * This is used to keep track of the number of hvc consoles
59 * spawned by this driver. This number is given as the first
60 * argument to hvc_alloc(). To correctly map an initial
61 * console spawned via hvc_instantiate to the console being
62 * hooked up via hvc_alloc, we need to pass the same vtermno.
63 *
64 * We also just assume the first console being initialised was
65 * the first one that got used as the initial console.
66 */
67 unsigned int next_vtermno;
68
69 /* All the console devices handled by this driver */
70 struct list_head consoles;
71};
72static struct ports_driver_data pdrvdata;
73
74DEFINE_SPINLOCK(pdrvdata_lock);
75
76/* This struct holds information that's relevant only for console ports */
77struct console {
78 /* We'll place all consoles in a list in the pdrvdata struct */
79 struct list_head list;
80
81 /* The hvc device associated with this console port */
82 struct hvc_struct *hvc;
83
84 /* The size of the console */
85 struct winsize ws;
86
87 /*
88 * This number identifies the number that we used to register
89 * with hvc in hvc_instantiate() and hvc_alloc(); this is the
90 * number passed on by the hvc callbacks to us to
91 * differentiate between the other console ports handled by
92 * this driver
93 */
94 u32 vtermno;
95};
96
97struct port_buffer {
98 char *buf;
99
100 /* size of the buffer in *buf above */
101 size_t size;
102
103 /* used length of the buffer */
104 size_t len;
105 /* offset in the buf from which to consume data */
106 size_t offset;
107};
108
109/*
110 * This is a per-device struct that stores data common to all the
111 * ports for that device (vdev->priv).
112 */
113struct ports_device {
114 /* Next portdev in the list, head is in the pdrvdata struct */
115 struct list_head list;
116
117 /*
118 * Workqueue handlers where we process deferred work after
119 * notification
120 */
121 struct work_struct control_work;
122
123 struct list_head ports;
124
125 /* To protect the list of ports */
126 spinlock_t ports_lock;
127
128 /* To protect the vq operations for the control channel */
129 spinlock_t cvq_lock;
130
131 /* The current config space is stored here */
132 struct virtio_console_config config;
133
134 /* The virtio device we're associated with */
135 struct virtio_device *vdev;
136
137 /*
138 * A couple of virtqueues for the control channel: one for
139 * guest->host transfers, one for host->guest transfers
140 */
141 struct virtqueue *c_ivq, *c_ovq;
142
143 /* Array of per-port IO virtqueues */
144 struct virtqueue **in_vqs, **out_vqs;
145
146 /* Used for numbering devices for sysfs and debugfs */
147 unsigned int drv_index;
148
149 /* Major number for this device. Ports will be created as minors. */
150 int chr_major;
151};
152
153/* This struct holds the per-port data */
154struct port {
155 /* Next port in the list, head is in the ports_device */
156 struct list_head list;
157
158 /* Pointer to the parent virtio_console device */
159 struct ports_device *portdev;
160
161 /* The current buffer from which data has to be fed to readers */
162 struct port_buffer *inbuf;
163
164 /*
165 * To protect the operations on the in_vq associated with this
166 * port. Has to be a spinlock because it can be called from
167 * interrupt context (get_char()).
168 */
169 spinlock_t inbuf_lock;
170
171 /* Protect the operations on the out_vq. */
172 spinlock_t outvq_lock;
173
174 /* The IO vqs for this port */
175 struct virtqueue *in_vq, *out_vq;
176
177 /* File in the debugfs directory that exposes this port's information */
178 struct dentry *debugfs_file;
179
180 /*
181 * The entries in this struct will be valid if this port is
182 * hooked up to an hvc console
183 */
184 struct console cons;
185
186 /* Each port associates with a separate char device */
187 struct cdev *cdev;
188 struct device *dev;
189
190 /* Reference-counting to handle port hot-unplugs and file operations */
191 struct kref kref;
192
193 /* A waitqueue for poll() or blocking read operations */
194 wait_queue_head_t waitqueue;
195
196 /* The 'name' of the port that we expose via sysfs properties */
197 char *name;
198
199 /* We can notify apps of host connect / disconnect events via SIGIO */
200 struct fasync_struct *async_queue;
201
202 /* The 'id' to identify the port with the Host */
203 u32 id;
204
205 bool outvq_full;
206
207 /* Is the host device open */
208 bool host_connected;
209
210 /* We should allow only one process to open a port */
211 bool guest_connected;
212};
213
214/* This is the very early arch-specified put chars function. */
215static int (*early_put_chars)(u32, const char *, int);
216
217static struct port *find_port_by_vtermno(u32 vtermno)
218{
219 struct port *port;
220 struct console *cons;
221 unsigned long flags;
222
223 spin_lock_irqsave(&pdrvdata_lock, flags);
224 list_for_each_entry(cons, &pdrvdata.consoles, list) {
225 if (cons->vtermno == vtermno) {
226 port = container_of(cons, struct port, cons);
227 goto out;
228 }
229 }
230 port = NULL;
231out:
232 spin_unlock_irqrestore(&pdrvdata_lock, flags);
233 return port;
234}
235
236static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
237 dev_t dev)
238{
239 struct port *port;
240 unsigned long flags;
241
242 spin_lock_irqsave(&portdev->ports_lock, flags);
243 list_for_each_entry(port, &portdev->ports, list)
244 if (port->cdev->dev == dev)
245 goto out;
246 port = NULL;
247out:
248 spin_unlock_irqrestore(&portdev->ports_lock, flags);
249
250 return port;
251}
252
253static struct port *find_port_by_devt(dev_t dev)
254{
255 struct ports_device *portdev;
256 struct port *port;
257 unsigned long flags;
258
259 spin_lock_irqsave(&pdrvdata_lock, flags);
260 list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
261 port = find_port_by_devt_in_portdev(portdev, dev);
262 if (port)
263 goto out;
264 }
265 port = NULL;
266out:
267 spin_unlock_irqrestore(&pdrvdata_lock, flags);
268 return port;
269}
270
271static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
272{
273 struct port *port;
274 unsigned long flags;
275
276 spin_lock_irqsave(&portdev->ports_lock, flags);
277 list_for_each_entry(port, &portdev->ports, list)
278 if (port->id == id)
279 goto out;
280 port = NULL;
281out:
282 spin_unlock_irqrestore(&portdev->ports_lock, flags);
283
284 return port;
285}
286
287static struct port *find_port_by_vq(struct ports_device *portdev,
288 struct virtqueue *vq)
289{
290 struct port *port;
291 unsigned long flags;
292
293 spin_lock_irqsave(&portdev->ports_lock, flags);
294 list_for_each_entry(port, &portdev->ports, list)
295 if (port->in_vq == vq || port->out_vq == vq)
296 goto out;
297 port = NULL;
298out:
299 spin_unlock_irqrestore(&portdev->ports_lock, flags);
300 return port;
301}
302
303static bool is_console_port(struct port *port)
304{
305 if (port->cons.hvc)
306 return true;
307 return false;
308}
309
310static inline bool use_multiport(struct ports_device *portdev)
311{
312 /*
313 * This condition can be true when put_chars is called from
314 * early_init
315 */
316 if (!portdev->vdev)
317 return 0;
318 return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
319}
320
321static void free_buf(struct port_buffer *buf)
322{
323 kfree(buf->buf);
324 kfree(buf);
325}
326
327static struct port_buffer *alloc_buf(size_t buf_size)
328{
329 struct port_buffer *buf;
330
331 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
332 if (!buf)
333 goto fail;
334 buf->buf = kzalloc(buf_size, GFP_KERNEL);
335 if (!buf->buf)
336 goto free_buf;
337 buf->len = 0;
338 buf->offset = 0;
339 buf->size = buf_size;
340 return buf;
341
342free_buf:
343 kfree(buf);
344fail:
345 return NULL;
346}
347
348/* Callers should take appropriate locks */
349static void *get_inbuf(struct port *port)
350{
351 struct port_buffer *buf;
352 struct virtqueue *vq;
353 unsigned int len;
354
355 vq = port->in_vq;
356 buf = virtqueue_get_buf(vq, &len);
357 if (buf) {
358 buf->len = len;
359 buf->offset = 0;
360 }
361 return buf;
362}
363
364/*
365 * Create a scatter-gather list representing our input buffer and put
366 * it in the queue.
367 *
368 * Callers should take appropriate locks.
369 */
370static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
371{
372 struct scatterlist sg[1];
373 int ret;
374
375 sg_init_one(sg, buf->buf, buf->size);
376
377 ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
378 virtqueue_kick(vq);
379 return ret;
380}
381
382/* Discard any unread data this port has. Callers lockers. */
383static void discard_port_data(struct port *port)
384{
385 struct port_buffer *buf;
386 struct virtqueue *vq;
387 unsigned int len;
388 int ret;
389
390 vq = port->in_vq;
391 if (port->inbuf)
392 buf = port->inbuf;
393 else
394 buf = virtqueue_get_buf(vq, &len);
395
396 ret = 0;
397 while (buf) {
398 if (add_inbuf(vq, buf) < 0) {
399 ret++;
400 free_buf(buf);
401 }
402 buf = virtqueue_get_buf(vq, &len);
403 }
404 port->inbuf = NULL;
405 if (ret)
406 dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
407 ret);
408}
409
410static bool port_has_data(struct port *port)
411{
412 unsigned long flags;
413 bool ret;
414
415 spin_lock_irqsave(&port->inbuf_lock, flags);
416 if (port->inbuf) {
417 ret = true;
418 goto out;
419 }
420 port->inbuf = get_inbuf(port);
421 if (port->inbuf) {
422 ret = true;
423 goto out;
424 }
425 ret = false;
426out:
427 spin_unlock_irqrestore(&port->inbuf_lock, flags);
428 return ret;
429}
430
431static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
432 unsigned int event, unsigned int value)
433{
434 struct scatterlist sg[1];
435 struct virtio_console_control cpkt;
436 struct virtqueue *vq;
437 unsigned int len;
438
439 if (!use_multiport(portdev))
440 return 0;
441
442 cpkt.id = port_id;
443 cpkt.event = event;
444 cpkt.value = value;
445
446 vq = portdev->c_ovq;
447
448 sg_init_one(sg, &cpkt, sizeof(cpkt));
449 if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
450 virtqueue_kick(vq);
451 while (!virtqueue_get_buf(vq, &len))
452 cpu_relax();
453 }
454 return 0;
455}
456
457static ssize_t send_control_msg(struct port *port, unsigned int event,
458 unsigned int value)
459{
460 /* Did the port get unplugged before userspace closed it? */
461 if (port->portdev)
462 return __send_control_msg(port->portdev, port->id, event, value);
463 return 0;
464}
465
466/* Callers must take the port->outvq_lock */
467static void reclaim_consumed_buffers(struct port *port)
468{
469 void *buf;
470 unsigned int len;
471
472 while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
473 kfree(buf);
474 port->outvq_full = false;
475 }
476}
477
478static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
479 bool nonblock)
480{
481 struct scatterlist sg[1];
482 struct virtqueue *out_vq;
483 ssize_t ret;
484 unsigned long flags;
485 unsigned int len;
486
487 out_vq = port->out_vq;
488
489 spin_lock_irqsave(&port->outvq_lock, flags);
490
491 reclaim_consumed_buffers(port);
492
493 sg_init_one(sg, in_buf, in_count);
494 ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf);
495
496 /* Tell Host to go! */
497 virtqueue_kick(out_vq);
498
499 if (ret < 0) {
500 in_count = 0;
501 goto done;
502 }
503
504 if (ret == 0)
505 port->outvq_full = true;
506
507 if (nonblock)
508 goto done;
509
510 /*
511 * Wait till the host acknowledges it pushed out the data we
512 * sent. This is done for data from the hvc_console; the tty
513 * operations are performed with spinlocks held so we can't
514 * sleep here. An alternative would be to copy the data to a
515 * buffer and relax the spinning requirement. The downside is
516 * we need to kmalloc a GFP_ATOMIC buffer each time the
517 * console driver writes something out.
518 */
519 while (!virtqueue_get_buf(out_vq, &len))
520 cpu_relax();
521done:
522 spin_unlock_irqrestore(&port->outvq_lock, flags);
523 /*
524 * We're expected to return the amount of data we wrote -- all
525 * of it
526 */
527 return in_count;
528}
529
530/*
531 * Give out the data that's requested from the buffer that we have
532 * queued up.
533 */
534static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
535 bool to_user)
536{
537 struct port_buffer *buf;
538 unsigned long flags;
539
540 if (!out_count || !port_has_data(port))
541 return 0;
542
543 buf = port->inbuf;
544 out_count = min(out_count, buf->len - buf->offset);
545
546 if (to_user) {
547 ssize_t ret;
548
549 ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
550 if (ret)
551 return -EFAULT;
552 } else {
553 memcpy(out_buf, buf->buf + buf->offset, out_count);
554 }
555
556 buf->offset += out_count;
557
558 if (buf->offset == buf->len) {
559 /*
560 * We're done using all the data in this buffer.
561 * Re-queue so that the Host can send us more data.
562 */
563 spin_lock_irqsave(&port->inbuf_lock, flags);
564 port->inbuf = NULL;
565
566 if (add_inbuf(port->in_vq, buf) < 0)
567 dev_warn(port->dev, "failed add_buf\n");
568
569 spin_unlock_irqrestore(&port->inbuf_lock, flags);
570 }
571 /* Return the number of bytes actually copied */
572 return out_count;
573}
574
575/* The condition that must be true for polling to end */
576static bool will_read_block(struct port *port)
577{
578 if (!port->guest_connected) {
579 /* Port got hot-unplugged. Let's exit. */
580 return false;
581 }
582 return !port_has_data(port) && port->host_connected;
583}
584
585static bool will_write_block(struct port *port)
586{
587 bool ret;
588
589 if (!port->guest_connected) {
590 /* Port got hot-unplugged. Let's exit. */
591 return false;
592 }
593 if (!port->host_connected)
594 return true;
595
596 spin_lock_irq(&port->outvq_lock);
597 /*
598 * Check if the Host has consumed any buffers since we last
599 * sent data (this is only applicable for nonblocking ports).
600 */
601 reclaim_consumed_buffers(port);
602 ret = port->outvq_full;
603 spin_unlock_irq(&port->outvq_lock);
604
605 return ret;
606}
607
608static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
609 size_t count, loff_t *offp)
610{
611 struct port *port;
612 ssize_t ret;
613
614 port = filp->private_data;
615
616 if (!port_has_data(port)) {
617 /*
618 * If nothing's connected on the host just return 0 in
619 * case of list_empty; this tells the userspace app
620 * that there's no connection
621 */
622 if (!port->host_connected)
623 return 0;
624 if (filp->f_flags & O_NONBLOCK)
625 return -EAGAIN;
626
627 ret = wait_event_interruptible(port->waitqueue,
628 !will_read_block(port));
629 if (ret < 0)
630 return ret;
631 }
632 /* Port got hot-unplugged. */
633 if (!port->guest_connected)
634 return -ENODEV;
635 /*
636 * We could've received a disconnection message while we were
637 * waiting for more data.
638 *
639 * This check is not clubbed in the if() statement above as we
640 * might receive some data as well as the host could get
641 * disconnected after we got woken up from our wait. So we
642 * really want to give off whatever data we have and only then
643 * check for host_connected.
644 */
645 if (!port_has_data(port) && !port->host_connected)
646 return 0;
647
648 return fill_readbuf(port, ubuf, count, true);
649}
650
651static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
652 size_t count, loff_t *offp)
653{
654 struct port *port;
655 char *buf;
656 ssize_t ret;
657 bool nonblock;
658
659 /* Userspace could be out to fool us */
660 if (!count)
661 return 0;
662
663 port = filp->private_data;
664
665 nonblock = filp->f_flags & O_NONBLOCK;
666
667 if (will_write_block(port)) {
668 if (nonblock)
669 return -EAGAIN;
670
671 ret = wait_event_interruptible(port->waitqueue,
672 !will_write_block(port));
673 if (ret < 0)
674 return ret;
675 }
676 /* Port got hot-unplugged. */
677 if (!port->guest_connected)
678 return -ENODEV;
679
680 count = min((size_t)(32 * 1024), count);
681
682 buf = kmalloc(count, GFP_KERNEL);
683 if (!buf)
684 return -ENOMEM;
685
686 ret = copy_from_user(buf, ubuf, count);
687 if (ret) {
688 ret = -EFAULT;
689 goto free_buf;
690 }
691
692 /*
693 * We now ask send_buf() to not spin for generic ports -- we
694 * can re-use the same code path that non-blocking file
695 * descriptors take for blocking file descriptors since the
696 * wait is already done and we're certain the write will go
697 * through to the host.
698 */
699 nonblock = true;
700 ret = send_buf(port, buf, count, nonblock);
701
702 if (nonblock && ret > 0)
703 goto out;
704
705free_buf:
706 kfree(buf);
707out:
708 return ret;
709}
710
711static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
712{
713 struct port *port;
714 unsigned int ret;
715
716 port = filp->private_data;
717 poll_wait(filp, &port->waitqueue, wait);
718
719 if (!port->guest_connected) {
720 /* Port got unplugged */
721 return POLLHUP;
722 }
723 ret = 0;
724 if (!will_read_block(port))
725 ret |= POLLIN | POLLRDNORM;
726 if (!will_write_block(port))
727 ret |= POLLOUT;
728 if (!port->host_connected)
729 ret |= POLLHUP;
730
731 return ret;
732}
733
734static void remove_port(struct kref *kref);
735
736static int port_fops_release(struct inode *inode, struct file *filp)
737{
738 struct port *port;
739
740 port = filp->private_data;
741
742 /* Notify host of port being closed */
743 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
744
745 spin_lock_irq(&port->inbuf_lock);
746 port->guest_connected = false;
747
748 discard_port_data(port);
749
750 spin_unlock_irq(&port->inbuf_lock);
751
752 spin_lock_irq(&port->outvq_lock);
753 reclaim_consumed_buffers(port);
754 spin_unlock_irq(&port->outvq_lock);
755
756 /*
757 * Locks aren't necessary here as a port can't be opened after
758 * unplug, and if a port isn't unplugged, a kref would already
759 * exist for the port. Plus, taking ports_lock here would
760 * create a dependency on other locks taken by functions
761 * inside remove_port if we're the last holder of the port,
762 * creating many problems.
763 */
764 kref_put(&port->kref, remove_port);
765
766 return 0;
767}
768
769static int port_fops_open(struct inode *inode, struct file *filp)
770{
771 struct cdev *cdev = inode->i_cdev;
772 struct port *port;
773 int ret;
774
775 port = find_port_by_devt(cdev->dev);
776 filp->private_data = port;
777
778 /* Prevent against a port getting hot-unplugged at the same time */
779 spin_lock_irq(&port->portdev->ports_lock);
780 kref_get(&port->kref);
781 spin_unlock_irq(&port->portdev->ports_lock);
782
783 /*
784 * Don't allow opening of console port devices -- that's done
785 * via /dev/hvc
786 */
787 if (is_console_port(port)) {
788 ret = -ENXIO;
789 goto out;
790 }
791
792 /* Allow only one process to open a particular port at a time */
793 spin_lock_irq(&port->inbuf_lock);
794 if (port->guest_connected) {
795 spin_unlock_irq(&port->inbuf_lock);
796 ret = -EMFILE;
797 goto out;
798 }
799
800 port->guest_connected = true;
801 spin_unlock_irq(&port->inbuf_lock);
802
803 spin_lock_irq(&port->outvq_lock);
804 /*
805 * There might be a chance that we missed reclaiming a few
806 * buffers in the window of the port getting previously closed
807 * and opening now.
808 */
809 reclaim_consumed_buffers(port);
810 spin_unlock_irq(&port->outvq_lock);
811
812 nonseekable_open(inode, filp);
813
814 /* Notify host of port being opened */
815 send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
816
817 return 0;
818out:
819 kref_put(&port->kref, remove_port);
820 return ret;
821}
822
823static int port_fops_fasync(int fd, struct file *filp, int mode)
824{
825 struct port *port;
826
827 port = filp->private_data;
828 return fasync_helper(fd, filp, mode, &port->async_queue);
829}
830
831/*
832 * The file operations that we support: programs in the guest can open
833 * a console device, read from it, write to it, poll for data and
834 * close it. The devices are at
835 * /dev/vport<device number>p<port number>
836 */
837static const struct file_operations port_fops = {
838 .owner = THIS_MODULE,
839 .open = port_fops_open,
840 .read = port_fops_read,
841 .write = port_fops_write,
842 .poll = port_fops_poll,
843 .release = port_fops_release,
844 .fasync = port_fops_fasync,
845 .llseek = no_llseek,
846};
847
848/*
849 * The put_chars() callback is pretty straightforward.
850 *
851 * We turn the characters into a scatter-gather list, add it to the
852 * output queue and then kick the Host. Then we sit here waiting for
853 * it to finish: inefficient in theory, but in practice
854 * implementations will do it immediately (lguest's Launcher does).
855 */
856static int put_chars(u32 vtermno, const char *buf, int count)
857{
858 struct port *port;
859
860 if (unlikely(early_put_chars))
861 return early_put_chars(vtermno, buf, count);
862
863 port = find_port_by_vtermno(vtermno);
864 if (!port)
865 return -EPIPE;
866
867 return send_buf(port, (void *)buf, count, false);
868}
869
870/*
871 * get_chars() is the callback from the hvc_console infrastructure
872 * when an interrupt is received.
873 *
874 * We call out to fill_readbuf that gets us the required data from the
875 * buffers that are queued up.
876 */
877static int get_chars(u32 vtermno, char *buf, int count)
878{
879 struct port *port;
880
881 /* If we've not set up the port yet, we have no input to give. */
882 if (unlikely(early_put_chars))
883 return 0;
884
885 port = find_port_by_vtermno(vtermno);
886 if (!port)
887 return -EPIPE;
888
889 /* If we don't have an input queue yet, we can't get input. */
890 BUG_ON(!port->in_vq);
891
892 return fill_readbuf(port, buf, count, false);
893}
894
895static void resize_console(struct port *port)
896{
897 struct virtio_device *vdev;
898
899 /* The port could have been hot-unplugged */
900 if (!port || !is_console_port(port))
901 return;
902
903 vdev = port->portdev->vdev;
904 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
905 hvc_resize(port->cons.hvc, port->cons.ws);
906}
907
908/* We set the configuration at this point, since we now have a tty */
909static int notifier_add_vio(struct hvc_struct *hp, int data)
910{
911 struct port *port;
912
913 port = find_port_by_vtermno(hp->vtermno);
914 if (!port)
915 return -EINVAL;
916
917 hp->irq_requested = 1;
918 resize_console(port);
919
920 return 0;
921}
922
923static void notifier_del_vio(struct hvc_struct *hp, int data)
924{
925 hp->irq_requested = 0;
926}
927
928/* The operations for console ports. */
929static const struct hv_ops hv_ops = {
930 .get_chars = get_chars,
931 .put_chars = put_chars,
932 .notifier_add = notifier_add_vio,
933 .notifier_del = notifier_del_vio,
934 .notifier_hangup = notifier_del_vio,
935};
936
937/*
938 * Console drivers are initialized very early so boot messages can go
939 * out, so we do things slightly differently from the generic virtio
940 * initialization of the net and block drivers.
941 *
942 * At this stage, the console is output-only. It's too early to set
943 * up a virtqueue, so we let the drivers do some boutique early-output
944 * thing.
945 */
946int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
947{
948 early_put_chars = put_chars;
949 return hvc_instantiate(0, 0, &hv_ops);
950}
951
952int init_port_console(struct port *port)
953{
954 int ret;
955
956 /*
957 * The Host's telling us this port is a console port. Hook it
958 * up with an hvc console.
959 *
960 * To set up and manage our virtual console, we call
961 * hvc_alloc().
962 *
963 * The first argument of hvc_alloc() is the virtual console
964 * number. The second argument is the parameter for the
965 * notification mechanism (like irq number). We currently
966 * leave this as zero, virtqueues have implicit notifications.
967 *
968 * The third argument is a "struct hv_ops" containing the
969 * put_chars() get_chars(), notifier_add() and notifier_del()
970 * pointers. The final argument is the output buffer size: we
971 * can do any size, so we put PAGE_SIZE here.
972 */
973 port->cons.vtermno = pdrvdata.next_vtermno;
974
975 port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
976 if (IS_ERR(port->cons.hvc)) {
977 ret = PTR_ERR(port->cons.hvc);
978 dev_err(port->dev,
979 "error %d allocating hvc for port\n", ret);
980 port->cons.hvc = NULL;
981 return ret;
982 }
983 spin_lock_irq(&pdrvdata_lock);
984 pdrvdata.next_vtermno++;
985 list_add_tail(&port->cons.list, &pdrvdata.consoles);
986 spin_unlock_irq(&pdrvdata_lock);
987 port->guest_connected = true;
988
989 /*
990 * Start using the new console output if this is the first
991 * console to come up.
992 */
993 if (early_put_chars)
994 early_put_chars = NULL;
995
996 /* Notify host of port being opened */
997 send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
998
999 return 0;
1000}
1001
1002static ssize_t show_port_name(struct device *dev,
1003 struct device_attribute *attr, char *buffer)
1004{
1005 struct port *port;
1006
1007 port = dev_get_drvdata(dev);
1008
1009 return sprintf(buffer, "%s\n", port->name);
1010}
1011
1012static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
1013
1014static struct attribute *port_sysfs_entries[] = {
1015 &dev_attr_name.attr,
1016 NULL
1017};
1018
1019static struct attribute_group port_attribute_group = {
1020 .name = NULL, /* put in device directory */
1021 .attrs = port_sysfs_entries,
1022};
1023
1024static int debugfs_open(struct inode *inode, struct file *filp)
1025{
1026 filp->private_data = inode->i_private;
1027 return 0;
1028}
1029
1030static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
1031 size_t count, loff_t *offp)
1032{
1033 struct port *port;
1034 char *buf;
1035 ssize_t ret, out_offset, out_count;
1036
1037 out_count = 1024;
1038 buf = kmalloc(out_count, GFP_KERNEL);
1039 if (!buf)
1040 return -ENOMEM;
1041
1042 port = filp->private_data;
1043 out_offset = 0;
1044 out_offset += snprintf(buf + out_offset, out_count,
1045 "name: %s\n", port->name ? port->name : "");
1046 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1047 "guest_connected: %d\n", port->guest_connected);
1048 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1049 "host_connected: %d\n", port->host_connected);
1050 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1051 "outvq_full: %d\n", port->outvq_full);
1052 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1053 "is_console: %s\n",
1054 is_console_port(port) ? "yes" : "no");
1055 out_offset += snprintf(buf + out_offset, out_count - out_offset,
1056 "console_vtermno: %u\n", port->cons.vtermno);
1057
1058 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
1059 kfree(buf);
1060 return ret;
1061}
1062
1063static const struct file_operations port_debugfs_ops = {
1064 .owner = THIS_MODULE,
1065 .open = debugfs_open,
1066 .read = debugfs_read,
1067};
1068
1069static void set_console_size(struct port *port, u16 rows, u16 cols)
1070{
1071 if (!port || !is_console_port(port))
1072 return;
1073
1074 port->cons.ws.ws_row = rows;
1075 port->cons.ws.ws_col = cols;
1076}
1077
1078static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
1079{
1080 struct port_buffer *buf;
1081 unsigned int nr_added_bufs;
1082 int ret;
1083
1084 nr_added_bufs = 0;
1085 do {
1086 buf = alloc_buf(PAGE_SIZE);
1087 if (!buf)
1088 break;
1089
1090 spin_lock_irq(lock);
1091 ret = add_inbuf(vq, buf);
1092 if (ret < 0) {
1093 spin_unlock_irq(lock);
1094 free_buf(buf);
1095 break;
1096 }
1097 nr_added_bufs++;
1098 spin_unlock_irq(lock);
1099 } while (ret > 0);
1100
1101 return nr_added_bufs;
1102}
1103
1104static void send_sigio_to_port(struct port *port)
1105{
1106 if (port->async_queue && port->guest_connected)
1107 kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
1108}
1109
1110static int add_port(struct ports_device *portdev, u32 id)
1111{
1112 char debugfs_name[16];
1113 struct port *port;
1114 struct port_buffer *buf;
1115 dev_t devt;
1116 unsigned int nr_added_bufs;
1117 int err;
1118
1119 port = kmalloc(sizeof(*port), GFP_KERNEL);
1120 if (!port) {
1121 err = -ENOMEM;
1122 goto fail;
1123 }
1124 kref_init(&port->kref);
1125
1126 port->portdev = portdev;
1127 port->id = id;
1128
1129 port->name = NULL;
1130 port->inbuf = NULL;
1131 port->cons.hvc = NULL;
1132 port->async_queue = NULL;
1133
1134 port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
1135
1136 port->host_connected = port->guest_connected = false;
1137
1138 port->outvq_full = false;
1139
1140 port->in_vq = portdev->in_vqs[port->id];
1141 port->out_vq = portdev->out_vqs[port->id];
1142
1143 port->cdev = cdev_alloc();
1144 if (!port->cdev) {
1145 dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
1146 err = -ENOMEM;
1147 goto free_port;
1148 }
1149 port->cdev->ops = &port_fops;
1150
1151 devt = MKDEV(portdev->chr_major, id);
1152 err = cdev_add(port->cdev, devt, 1);
1153 if (err < 0) {
1154 dev_err(&port->portdev->vdev->dev,
1155 "Error %d adding cdev for port %u\n", err, id);
1156 goto free_cdev;
1157 }
1158 port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
1159 devt, port, "vport%up%u",
1160 port->portdev->drv_index, id);
1161 if (IS_ERR(port->dev)) {
1162 err = PTR_ERR(port->dev);
1163 dev_err(&port->portdev->vdev->dev,
1164 "Error %d creating device for port %u\n",
1165 err, id);
1166 goto free_cdev;
1167 }
1168
1169 spin_lock_init(&port->inbuf_lock);
1170 spin_lock_init(&port->outvq_lock);
1171 init_waitqueue_head(&port->waitqueue);
1172
1173 /* Fill the in_vq with buffers so the host can send us data. */
1174 nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
1175 if (!nr_added_bufs) {
1176 dev_err(port->dev, "Error allocating inbufs\n");
1177 err = -ENOMEM;
1178 goto free_device;
1179 }
1180
1181 /*
1182 * If we're not using multiport support, this has to be a console port
1183 */
1184 if (!use_multiport(port->portdev)) {
1185 err = init_port_console(port);
1186 if (err)
1187 goto free_inbufs;
1188 }
1189
1190 spin_lock_irq(&portdev->ports_lock);
1191 list_add_tail(&port->list, &port->portdev->ports);
1192 spin_unlock_irq(&portdev->ports_lock);
1193
1194 /*
1195 * Tell the Host we're set so that it can send us various
1196 * configuration parameters for this port (eg, port name,
1197 * caching, whether this is a console port, etc.)
1198 */
1199 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1200
1201 if (pdrvdata.debugfs_dir) {
1202 /*
1203 * Finally, create the debugfs file that we can use to
1204 * inspect a port's state at any time
1205 */
1206 sprintf(debugfs_name, "vport%up%u",
1207 port->portdev->drv_index, id);
1208 port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
1209 pdrvdata.debugfs_dir,
1210 port,
1211 &port_debugfs_ops);
1212 }
1213 return 0;
1214
1215free_inbufs:
1216 while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
1217 free_buf(buf);
1218free_device:
1219 device_destroy(pdrvdata.class, port->dev->devt);
1220free_cdev:
1221 cdev_del(port->cdev);
1222free_port:
1223 kfree(port);
1224fail:
1225 /* The host might want to notify management sw about port add failure */
1226 __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
1227 return err;
1228}
1229
1230/* No users remain, remove all port-specific data. */
1231static void remove_port(struct kref *kref)
1232{
1233 struct port *port;
1234
1235 port = container_of(kref, struct port, kref);
1236
1237 sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
1238 device_destroy(pdrvdata.class, port->dev->devt);
1239 cdev_del(port->cdev);
1240
1241 kfree(port->name);
1242
1243 debugfs_remove(port->debugfs_file);
1244
1245 kfree(port);
1246}
1247
1248/*
1249 * Port got unplugged. Remove port from portdev's list and drop the
1250 * kref reference. If no userspace has this port opened, it will
1251 * result in immediate removal the port.
1252 */
1253static void unplug_port(struct port *port)
1254{
1255 struct port_buffer *buf;
1256
1257 spin_lock_irq(&port->portdev->ports_lock);
1258 list_del(&port->list);
1259 spin_unlock_irq(&port->portdev->ports_lock);
1260
1261 if (port->guest_connected) {
1262 port->guest_connected = false;
1263 port->host_connected = false;
1264 wake_up_interruptible(&port->waitqueue);
1265
1266 /* Let the app know the port is going down. */
1267 send_sigio_to_port(port);
1268 }
1269
1270 if (is_console_port(port)) {
1271 spin_lock_irq(&pdrvdata_lock);
1272 list_del(&port->cons.list);
1273 spin_unlock_irq(&pdrvdata_lock);
1274#if 0
1275 /*
1276 * hvc_remove() not called as removing one hvc port
1277 * results in other hvc ports getting frozen.
1278 *
1279 * Once this is resolved in hvc, this functionality
1280 * will be enabled. Till that is done, the -EPIPE
1281 * return from get_chars() above will help
1282 * hvc_console.c to clean up on ports we remove here.
1283 */
1284 hvc_remove(port->cons.hvc);
1285#endif
1286 }
1287
1288 /* Remove unused data this port might have received. */
1289 discard_port_data(port);
1290
1291 reclaim_consumed_buffers(port);
1292
1293 /* Remove buffers we queued up for the Host to send us data in. */
1294 while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
1295 free_buf(buf);
1296
1297 /*
1298 * We should just assume the device itself has gone off --
1299 * else a close on an open port later will try to send out a
1300 * control message.
1301 */
1302 port->portdev = NULL;
1303
1304 /*
1305 * Locks around here are not necessary - a port can't be
1306 * opened after we removed the port struct from ports_list
1307 * above.
1308 */
1309 kref_put(&port->kref, remove_port);
1310}
1311
1312/* Any private messages that the Host and Guest want to share */
1313static void handle_control_message(struct ports_device *portdev,
1314 struct port_buffer *buf)
1315{
1316 struct virtio_console_control *cpkt;
1317 struct port *port;
1318 size_t name_size;
1319 int err;
1320
1321 cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
1322
1323 port = find_port_by_id(portdev, cpkt->id);
1324 if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
1325 /* No valid header at start of buffer. Drop it. */
1326 dev_dbg(&portdev->vdev->dev,
1327 "Invalid index %u in control packet\n", cpkt->id);
1328 return;
1329 }
1330
1331 switch (cpkt->event) {
1332 case VIRTIO_CONSOLE_PORT_ADD:
1333 if (port) {
1334 dev_dbg(&portdev->vdev->dev,
1335 "Port %u already added\n", port->id);
1336 send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
1337 break;
1338 }
1339 if (cpkt->id >= portdev->config.max_nr_ports) {
1340 dev_warn(&portdev->vdev->dev,
1341 "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
1342 cpkt->id, portdev->config.max_nr_ports - 1);
1343 break;
1344 }
1345 add_port(portdev, cpkt->id);
1346 break;
1347 case VIRTIO_CONSOLE_PORT_REMOVE:
1348 unplug_port(port);
1349 break;
1350 case VIRTIO_CONSOLE_CONSOLE_PORT:
1351 if (!cpkt->value)
1352 break;
1353 if (is_console_port(port))
1354 break;
1355
1356 init_port_console(port);
1357 /*
1358 * Could remove the port here in case init fails - but
1359 * have to notify the host first.
1360 */
1361 break;
1362 case VIRTIO_CONSOLE_RESIZE: {
1363 struct {
1364 __u16 rows;
1365 __u16 cols;
1366 } size;
1367
1368 if (!is_console_port(port))
1369 break;
1370
1371 memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
1372 sizeof(size));
1373 set_console_size(port, size.rows, size.cols);
1374
1375 port->cons.hvc->irq_requested = 1;
1376 resize_console(port);
1377 break;
1378 }
1379 case VIRTIO_CONSOLE_PORT_OPEN:
1380 port->host_connected = cpkt->value;
1381 wake_up_interruptible(&port->waitqueue);
1382 /*
1383 * If the host port got closed and the host had any
1384 * unconsumed buffers, we'll be able to reclaim them
1385 * now.
1386 */
1387 spin_lock_irq(&port->outvq_lock);
1388 reclaim_consumed_buffers(port);
1389 spin_unlock_irq(&port->outvq_lock);
1390
1391 /*
1392 * If the guest is connected, it'll be interested in
1393 * knowing the host connection state changed.
1394 */
1395 send_sigio_to_port(port);
1396 break;
1397 case VIRTIO_CONSOLE_PORT_NAME:
1398 /*
1399 * Skip the size of the header and the cpkt to get the size
1400 * of the name that was sent
1401 */
1402 name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
1403
1404 port->name = kmalloc(name_size, GFP_KERNEL);
1405 if (!port->name) {
1406 dev_err(port->dev,
1407 "Not enough space to store port name\n");
1408 break;
1409 }
1410 strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
1411 name_size - 1);
1412 port->name[name_size - 1] = 0;
1413
1414 /*
1415 * Since we only have one sysfs attribute, 'name',
1416 * create it only if we have a name for the port.
1417 */
1418 err = sysfs_create_group(&port->dev->kobj,
1419 &port_attribute_group);
1420 if (err) {
1421 dev_err(port->dev,
1422 "Error %d creating sysfs device attributes\n",
1423 err);
1424 } else {
1425 /*
1426 * Generate a udev event so that appropriate
1427 * symlinks can be created based on udev
1428 * rules.
1429 */
1430 kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
1431 }
1432 break;
1433 }
1434}
1435
1436static void control_work_handler(struct work_struct *work)
1437{
1438 struct ports_device *portdev;
1439 struct virtqueue *vq;
1440 struct port_buffer *buf;
1441 unsigned int len;
1442
1443 portdev = container_of(work, struct ports_device, control_work);
1444 vq = portdev->c_ivq;
1445
1446 spin_lock(&portdev->cvq_lock);
1447 while ((buf = virtqueue_get_buf(vq, &len))) {
1448 spin_unlock(&portdev->cvq_lock);
1449
1450 buf->len = len;
1451 buf->offset = 0;
1452
1453 handle_control_message(portdev, buf);
1454
1455 spin_lock(&portdev->cvq_lock);
1456 if (add_inbuf(portdev->c_ivq, buf) < 0) {
1457 dev_warn(&portdev->vdev->dev,
1458 "Error adding buffer to queue\n");
1459 free_buf(buf);
1460 }
1461 }
1462 spin_unlock(&portdev->cvq_lock);
1463}
1464
1465static void in_intr(struct virtqueue *vq)
1466{
1467 struct port *port;
1468 unsigned long flags;
1469
1470 port = find_port_by_vq(vq->vdev->priv, vq);
1471 if (!port)
1472 return;
1473
1474 spin_lock_irqsave(&port->inbuf_lock, flags);
1475 if (!port->inbuf)
1476 port->inbuf = get_inbuf(port);
1477
1478 /*
1479 * Don't queue up data when port is closed. This condition
1480 * can be reached when a console port is not yet connected (no
1481 * tty is spawned) and the host sends out data to console
1482 * ports. For generic serial ports, the host won't
1483 * (shouldn't) send data till the guest is connected.
1484 */
1485 if (!port->guest_connected)
1486 discard_port_data(port);
1487
1488 spin_unlock_irqrestore(&port->inbuf_lock, flags);
1489
1490 wake_up_interruptible(&port->waitqueue);
1491
1492 /* Send a SIGIO indicating new data in case the process asked for it */
1493 send_sigio_to_port(port);
1494
1495 if (is_console_port(port) && hvc_poll(port->cons.hvc))
1496 hvc_kick();
1497}
1498
1499static void control_intr(struct virtqueue *vq)
1500{
1501 struct ports_device *portdev;
1502
1503 portdev = vq->vdev->priv;
1504 schedule_work(&portdev->control_work);
1505}
1506
1507static void config_intr(struct virtio_device *vdev)
1508{
1509 struct ports_device *portdev;
1510
1511 portdev = vdev->priv;
1512
1513 if (!use_multiport(portdev)) {
1514 struct port *port;
1515 u16 rows, cols;
1516
1517 vdev->config->get(vdev,
1518 offsetof(struct virtio_console_config, cols),
1519 &cols, sizeof(u16));
1520 vdev->config->get(vdev,
1521 offsetof(struct virtio_console_config, rows),
1522 &rows, sizeof(u16));
1523
1524 port = find_port_by_id(portdev, 0);
1525 set_console_size(port, rows, cols);
1526
1527 /*
1528 * We'll use this way of resizing only for legacy
1529 * support. For newer userspace
1530 * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
1531 * to indicate console size changes so that it can be
1532 * done per-port.
1533 */
1534 resize_console(port);
1535 }
1536}
1537
1538static int init_vqs(struct ports_device *portdev)
1539{
1540 vq_callback_t **io_callbacks;
1541 char **io_names;
1542 struct virtqueue **vqs;
1543 u32 i, j, nr_ports, nr_queues;
1544 int err;
1545
1546 nr_ports = portdev->config.max_nr_ports;
1547 nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
1548
1549 vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
1550 io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
1551 io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
1552 portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1553 GFP_KERNEL);
1554 portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
1555 GFP_KERNEL);
1556 if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
1557 !portdev->out_vqs) {
1558 err = -ENOMEM;
1559 goto free;
1560 }
1561
1562 /*
1563 * For backward compat (newer host but older guest), the host
1564 * spawns a console port first and also inits the vqs for port
1565 * 0 before others.
1566 */
1567 j = 0;
1568 io_callbacks[j] = in_intr;
1569 io_callbacks[j + 1] = NULL;
1570 io_names[j] = "input";
1571 io_names[j + 1] = "output";
1572 j += 2;
1573
1574 if (use_multiport(portdev)) {
1575 io_callbacks[j] = control_intr;
1576 io_callbacks[j + 1] = NULL;
1577 io_names[j] = "control-i";
1578 io_names[j + 1] = "control-o";
1579
1580 for (i = 1; i < nr_ports; i++) {
1581 j += 2;
1582 io_callbacks[j] = in_intr;
1583 io_callbacks[j + 1] = NULL;
1584 io_names[j] = "input";
1585 io_names[j + 1] = "output";
1586 }
1587 }
1588 /* Find the queues. */
1589 err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
1590 io_callbacks,
1591 (const char **)io_names);
1592 if (err)
1593 goto free;
1594
1595 j = 0;
1596 portdev->in_vqs[0] = vqs[0];
1597 portdev->out_vqs[0] = vqs[1];
1598 j += 2;
1599 if (use_multiport(portdev)) {
1600 portdev->c_ivq = vqs[j];
1601 portdev->c_ovq = vqs[j + 1];
1602
1603 for (i = 1; i < nr_ports; i++) {
1604 j += 2;
1605 portdev->in_vqs[i] = vqs[j];
1606 portdev->out_vqs[i] = vqs[j + 1];
1607 }
1608 }
1609 kfree(io_names);
1610 kfree(io_callbacks);
1611 kfree(vqs);
1612
1613 return 0;
1614
1615free:
1616 kfree(portdev->out_vqs);
1617 kfree(portdev->in_vqs);
1618 kfree(io_names);
1619 kfree(io_callbacks);
1620 kfree(vqs);
1621
1622 return err;
1623}
1624
1625static const struct file_operations portdev_fops = {
1626 .owner = THIS_MODULE,
1627};
1628
1629/*
1630 * Once we're further in boot, we get probed like any other virtio
1631 * device.
1632 *
1633 * If the host also supports multiple console ports, we check the
1634 * config space to see how many ports the host has spawned. We
1635 * initialize each port found.
1636 */
1637static int __devinit virtcons_probe(struct virtio_device *vdev)
1638{
1639 struct ports_device *portdev;
1640 int err;
1641 bool multiport;
1642
1643 portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
1644 if (!portdev) {
1645 err = -ENOMEM;
1646 goto fail;
1647 }
1648
1649 /* Attach this portdev to this virtio_device, and vice-versa. */
1650 portdev->vdev = vdev;
1651 vdev->priv = portdev;
1652
1653 spin_lock_irq(&pdrvdata_lock);
1654 portdev->drv_index = pdrvdata.index++;
1655 spin_unlock_irq(&pdrvdata_lock);
1656
1657 portdev->chr_major = register_chrdev(0, "virtio-portsdev",
1658 &portdev_fops);
1659 if (portdev->chr_major < 0) {
1660 dev_err(&vdev->dev,
1661 "Error %d registering chrdev for device %u\n",
1662 portdev->chr_major, portdev->drv_index);
1663 err = portdev->chr_major;
1664 goto free;
1665 }
1666
1667 multiport = false;
1668 portdev->config.max_nr_ports = 1;
1669 if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
1670 multiport = true;
1671 vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
1672
1673 vdev->config->get(vdev, offsetof(struct virtio_console_config,
1674 max_nr_ports),
1675 &portdev->config.max_nr_ports,
1676 sizeof(portdev->config.max_nr_ports));
1677 }
1678
1679 /* Let the Host know we support multiple ports.*/
1680 vdev->config->finalize_features(vdev);
1681
1682 err = init_vqs(portdev);
1683 if (err < 0) {
1684 dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
1685 goto free_chrdev;
1686 }
1687
1688 spin_lock_init(&portdev->ports_lock);
1689 INIT_LIST_HEAD(&portdev->ports);
1690
1691 if (multiport) {
1692 unsigned int nr_added_bufs;
1693
1694 spin_lock_init(&portdev->cvq_lock);
1695 INIT_WORK(&portdev->control_work, &control_work_handler);
1696
1697 nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
1698 if (!nr_added_bufs) {
1699 dev_err(&vdev->dev,
1700 "Error allocating buffers for control queue\n");
1701 err = -ENOMEM;
1702 goto free_vqs;
1703 }
1704 } else {
1705 /*
1706 * For backward compatibility: Create a console port
1707 * if we're running on older host.
1708 */
1709 add_port(portdev, 0);
1710 }
1711
1712 spin_lock_irq(&pdrvdata_lock);
1713 list_add_tail(&portdev->list, &pdrvdata.portdevs);
1714 spin_unlock_irq(&pdrvdata_lock);
1715
1716 __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
1717 VIRTIO_CONSOLE_DEVICE_READY, 1);
1718 return 0;
1719
1720free_vqs:
1721 /* The host might want to notify mgmt sw about device add failure */
1722 __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
1723 VIRTIO_CONSOLE_DEVICE_READY, 0);
1724 vdev->config->del_vqs(vdev);
1725 kfree(portdev->in_vqs);
1726 kfree(portdev->out_vqs);
1727free_chrdev:
1728 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
1729free:
1730 kfree(portdev);
1731fail:
1732 return err;
1733}
1734
1735static void virtcons_remove(struct virtio_device *vdev)
1736{
1737 struct ports_device *portdev;
1738 struct port *port, *port2;
1739
1740 portdev = vdev->priv;
1741
1742 spin_lock_irq(&pdrvdata_lock);
1743 list_del(&portdev->list);
1744 spin_unlock_irq(&pdrvdata_lock);
1745
1746 /* Disable interrupts for vqs */
1747 vdev->config->reset(vdev);
1748 /* Finish up work that's lined up */
1749 cancel_work_sync(&portdev->control_work);
1750
1751 list_for_each_entry_safe(port, port2, &portdev->ports, list)
1752 unplug_port(port);
1753
1754 unregister_chrdev(portdev->chr_major, "virtio-portsdev");
1755
1756 /*
1757 * When yanking out a device, we immediately lose the
1758 * (device-side) queues. So there's no point in keeping the
1759 * guest side around till we drop our final reference. This
1760 * also means that any ports which are in an open state will
1761 * have to just stop using the port, as the vqs are going
1762 * away.
1763 */
1764 if (use_multiport(portdev)) {
1765 struct port_buffer *buf;
1766 unsigned int len;
1767
1768 while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
1769 free_buf(buf);
1770
1771 while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
1772 free_buf(buf);
1773 }
1774
1775 vdev->config->del_vqs(vdev);
1776 kfree(portdev->in_vqs);
1777 kfree(portdev->out_vqs);
1778
1779 kfree(portdev);
1780}
1781
1782static struct virtio_device_id id_table[] = {
1783 { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
1784 { 0 },
1785};
1786
1787static unsigned int features[] = {
1788 VIRTIO_CONSOLE_F_SIZE,
1789 VIRTIO_CONSOLE_F_MULTIPORT,
1790};
1791
1792static struct virtio_driver virtio_console = {
1793 .feature_table = features,
1794 .feature_table_size = ARRAY_SIZE(features),
1795 .driver.name = KBUILD_MODNAME,
1796 .driver.owner = THIS_MODULE,
1797 .id_table = id_table,
1798 .probe = virtcons_probe,
1799 .remove = virtcons_remove,
1800 .config_changed = config_intr,
1801};
1802
1803static int __init init(void)
1804{
1805 int err;
1806
1807 pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
1808 if (IS_ERR(pdrvdata.class)) {
1809 err = PTR_ERR(pdrvdata.class);
1810 pr_err("Error %d creating virtio-ports class\n", err);
1811 return err;
1812 }
1813
1814 pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
1815 if (!pdrvdata.debugfs_dir) {
1816 pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
1817 PTR_ERR(pdrvdata.debugfs_dir));
1818 }
1819 INIT_LIST_HEAD(&pdrvdata.consoles);
1820 INIT_LIST_HEAD(&pdrvdata.portdevs);
1821
1822 return register_virtio_driver(&virtio_console);
1823}
1824
1825static void __exit fini(void)
1826{
1827 unregister_virtio_driver(&virtio_console);
1828
1829 class_destroy(pdrvdata.class);
1830 if (pdrvdata.debugfs_dir)
1831 debugfs_remove_recursive(pdrvdata.debugfs_dir);
1832}
1833module_init(init);
1834module_exit(fini);
1835
1836MODULE_DEVICE_TABLE(virtio, id_table);
1837MODULE_DESCRIPTION("Virtio console driver");
1838MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-12 03:01:35 -0500