device.c 49.5 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4
/*
 *  drivers/s390/cio/device.c
 *  bus driver for ccw devices
 *
Cornelia Huck's avatar
Cornelia Huck committed
5
 *    Copyright IBM Corp. 2002,2008
Linus Torvalds's avatar
Linus Torvalds committed
6
 *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
7
 *		 Cornelia Huck (cornelia.huck@de.ibm.com)
Linus Torvalds's avatar
Linus Torvalds committed
8 9 10 11 12 13 14 15 16 17 18
 *		 Martin Schwidefsky (schwidefsky@de.ibm.com)
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/workqueue.h>
19
#include <linux/timer.h>
Linus Torvalds's avatar
Linus Torvalds committed
20 21 22

#include <asm/ccwdev.h>
#include <asm/cio.h>
Tim Schmielau's avatar
Tim Schmielau committed
23
#include <asm/param.h>		/* HZ */
24
#include <asm/cmb.h>
25
#include <asm/isc.h>
Linus Torvalds's avatar
Linus Torvalds committed
26

27
#include "chp.h"
Linus Torvalds's avatar
Linus Torvalds committed
28
#include "cio.h"
29
#include "cio_debug.h"
Linus Torvalds's avatar
Linus Torvalds committed
30 31 32
#include "css.h"
#include "device.h"
#include "ioasm.h"
33
#include "io_sch.h"
34
#include "blacklist.h"
Linus Torvalds's avatar
Linus Torvalds committed
35

36
static struct timer_list recovery_timer;
37
static DEFINE_SPINLOCK(recovery_lock);
38 39 40
static int recovery_phase;
static const unsigned long recovery_delay[] = { 3, 30, 300 };

Linus Torvalds's avatar
Linus Torvalds committed
41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
/******************* bus type handling ***********************/

/* The Linux driver model distinguishes between a bus type and
 * the bus itself. Of course we only have one channel
 * subsystem driver and one channel system per machine, but
 * we still use the abstraction. T.R. says it's a good idea. */
static int
ccw_bus_match (struct device * dev, struct device_driver * drv)
{
	struct ccw_device *cdev = to_ccwdev(dev);
	struct ccw_driver *cdrv = to_ccwdrv(drv);
	const struct ccw_device_id *ids = cdrv->ids, *found;

	if (!ids)
		return 0;

	found = ccw_device_id_match(ids, &cdev->id);
	if (!found)
		return 0;

	cdev->id.driver_info = found->driver_info;

	return 1;
}

66 67 68
/* Store modalias string delimited by prefix/suffix string into buffer with
 * specified size. Return length of resulting string (excluding trailing '\0')
 * even if string doesn't fit buffer (snprintf semantics). */
69
static int snprint_alias(char *buf, size_t size,
70
			 struct ccw_device_id *id, const char *suffix)
Linus Torvalds's avatar
Linus Torvalds committed
71
{
72
	int len;
Linus Torvalds's avatar
Linus Torvalds committed
73

74
	len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
75 76 77 78
	if (len > size)
		return len;
	buf += len;
	size -= len;
Linus Torvalds's avatar
Linus Torvalds committed
79

80 81 82 83 84
	if (id->dev_type != 0)
		len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
				id->dev_model, suffix);
	else
		len += snprintf(buf, size, "dtdm%s", suffix);
Linus Torvalds's avatar
Linus Torvalds committed
85

86 87 88 89 90
	return len;
}

/* Set up environment variables for ccw device uevent. Return 0 on success,
 * non-zero otherwise. */
91
static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
92 93 94
{
	struct ccw_device *cdev = to_ccwdev(dev);
	struct ccw_device_id *id = &(cdev->id);
95 96
	int ret;
	char modalias_buf[30];
Linus Torvalds's avatar
Linus Torvalds committed
97

98
	/* CU_TYPE= */
99
	ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
100 101
	if (ret)
		return ret;
102 103

	/* CU_MODEL= */
104
	ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
105 106
	if (ret)
		return ret;
Linus Torvalds's avatar
Linus Torvalds committed
107 108

	/* The next two can be zero, that's ok for us */
109
	/* DEV_TYPE= */
110
	ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
111 112
	if (ret)
		return ret;
Linus Torvalds's avatar
Linus Torvalds committed
113

114
	/* DEV_MODEL= */
115
	ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
116 117
	if (ret)
		return ret;
118 119

	/* MODALIAS=  */
120
	snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
121 122
	ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
	return ret;
Linus Torvalds's avatar
Linus Torvalds committed
123 124
}

125
struct bus_type ccw_bus_type;
Linus Torvalds's avatar
Linus Torvalds committed
126

127 128 129
static void io_subchannel_irq(struct subchannel *);
static int io_subchannel_probe(struct subchannel *);
static int io_subchannel_remove(struct subchannel *);
130
static void io_subchannel_shutdown(struct subchannel *);
Cornelia Huck's avatar
Cornelia Huck committed
131
static int io_subchannel_sch_event(struct subchannel *, int);
132 133
static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
				   int);
Linus Torvalds's avatar
Linus Torvalds committed
134

135 136 137 138 139 140
static struct css_device_id io_subchannel_ids[] = {
	{ .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
	{ /* end of list */ },
};
MODULE_DEVICE_TABLE(css, io_subchannel_ids);

141
static struct css_driver io_subchannel_driver = {
142
	.owner = THIS_MODULE,
143
	.subchannel_type = io_subchannel_ids,
144
	.name = "io_subchannel",
Linus Torvalds's avatar
Linus Torvalds committed
145
	.irq = io_subchannel_irq,
Cornelia Huck's avatar
Cornelia Huck committed
146 147
	.sch_event = io_subchannel_sch_event,
	.chp_event = io_subchannel_chp_event,
148 149 150
	.probe = io_subchannel_probe,
	.remove = io_subchannel_remove,
	.shutdown = io_subchannel_shutdown,
Linus Torvalds's avatar
Linus Torvalds committed
151 152 153
};

struct workqueue_struct *ccw_device_work;
154 155
wait_queue_head_t ccw_device_init_wq;
atomic_t ccw_device_init_count;
Linus Torvalds's avatar
Linus Torvalds committed
156

157 158
static void recovery_func(unsigned long data);

Linus Torvalds's avatar
Linus Torvalds committed
159 160 161 162 163 164 165
static int __init
init_ccw_bus_type (void)
{
	int ret;

	init_waitqueue_head(&ccw_device_init_wq);
	atomic_set(&ccw_device_init_count, 0);
166
	setup_timer(&recovery_timer, recovery_func, 0);
Linus Torvalds's avatar
Linus Torvalds committed
167 168 169 170 171 172 173 174 175 176 177 178

	ccw_device_work = create_singlethread_workqueue("cio");
	if (!ccw_device_work)
		return -ENOMEM; /* FIXME: better errno ? */
	slow_path_wq = create_singlethread_workqueue("kslowcrw");
	if (!slow_path_wq) {
		ret = -ENOMEM; /* FIXME: better errno ? */
		goto out_err;
	}
	if ((ret = bus_register (&ccw_bus_type)))
		goto out_err;

179 180
	ret = css_driver_register(&io_subchannel_driver);
	if (ret)
Linus Torvalds's avatar
Linus Torvalds committed
181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197
		goto out_err;

	wait_event(ccw_device_init_wq,
		   atomic_read(&ccw_device_init_count) == 0);
	flush_workqueue(ccw_device_work);
	return 0;
out_err:
	if (ccw_device_work)
		destroy_workqueue(ccw_device_work);
	if (slow_path_wq)
		destroy_workqueue(slow_path_wq);
	return ret;
}

static void __exit
cleanup_ccw_bus_type (void)
{
198
	css_driver_unregister(&io_subchannel_driver);
Linus Torvalds's avatar
Linus Torvalds committed
199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216
	bus_unregister(&ccw_bus_type);
	destroy_workqueue(ccw_device_work);
}

subsys_initcall(init_ccw_bus_type);
module_exit(cleanup_ccw_bus_type);

/************************ device handling **************************/

/*
 * A ccw_device has some interfaces in sysfs in addition to the
 * standard ones.
 * The following entries are designed to export the information which
 * resided in 2.4 in /proc/subchannels. Subchannel and device number
 * are obvious, so they don't have an entry :)
 * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 */
static ssize_t
217
chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
Linus Torvalds's avatar
Linus Torvalds committed
218 219
{
	struct subchannel *sch = to_subchannel(dev);
220
	struct chsc_ssd_info *ssd = &sch->ssd_info;
Linus Torvalds's avatar
Linus Torvalds committed
221 222
	ssize_t ret = 0;
	int chp;
223 224 225 226 227 228 229 230 231
	int mask;

	for (chp = 0; chp < 8; chp++) {
		mask = 0x80 >> chp;
		if (ssd->path_mask & mask)
			ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
		else
			ret += sprintf(buf + ret, "00 ");
	}
Linus Torvalds's avatar
Linus Torvalds committed
232 233 234 235 236
	ret += sprintf (buf+ret, "\n");
	return min((ssize_t)PAGE_SIZE, ret);
}

static ssize_t
237
pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
Linus Torvalds's avatar
Linus Torvalds committed
238 239 240 241 242 243 244 245 246
{
	struct subchannel *sch = to_subchannel(dev);
	struct pmcw *pmcw = &sch->schib.pmcw;

	return sprintf (buf, "%02x %02x %02x\n",
			pmcw->pim, pmcw->pam, pmcw->pom);
}

static ssize_t
247
devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds's avatar
Linus Torvalds committed
248 249 250 251 252 253 254 255 256 257 258 259
{
	struct ccw_device *cdev = to_ccwdev(dev);
	struct ccw_device_id *id = &(cdev->id);

	if (id->dev_type != 0)
		return sprintf(buf, "%04x/%02x\n",
				id->dev_type, id->dev_model);
	else
		return sprintf(buf, "n/a\n");
}

static ssize_t
260
cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds's avatar
Linus Torvalds committed
261 262 263 264 265 266 267 268
{
	struct ccw_device *cdev = to_ccwdev(dev);
	struct ccw_device_id *id = &(cdev->id);

	return sprintf(buf, "%04x/%02x\n",
		       id->cu_type, id->cu_model);
}

269 270 271 272 273
static ssize_t
modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
{
	struct ccw_device *cdev = to_ccwdev(dev);
	struct ccw_device_id *id = &(cdev->id);
274
	int len;
275

276
	len = snprint_alias(buf, PAGE_SIZE, id, "\n");
277 278

	return len > PAGE_SIZE ? PAGE_SIZE : len;
279 280
}

Linus Torvalds's avatar
Linus Torvalds committed
281
static ssize_t
282
online_show (struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds's avatar
Linus Torvalds committed
283 284 285 286 287 288
{
	struct ccw_device *cdev = to_ccwdev(dev);

	return sprintf(buf, cdev->online ? "1\n" : "0\n");
}

289 290 291 292 293
int ccw_device_is_orphan(struct ccw_device *cdev)
{
	return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
}

294
static void ccw_device_unregister(struct ccw_device *cdev)
295 296
{
	if (test_and_clear_bit(1, &cdev->private->registered))
297
		device_del(&cdev->dev);
298 299
}

300
static void ccw_device_remove_orphan_cb(struct work_struct *work)
301
{
302 303
	struct ccw_device_private *priv;
	struct ccw_device *cdev;
304

305 306
	priv = container_of(work, struct ccw_device_private, kick_work);
	cdev = priv->cdev;
307 308
	ccw_device_unregister(cdev);
	put_device(&cdev->dev);
309 310
	/* Release cdev reference for workqueue processing. */
	put_device(&cdev->dev);
311 312
}

313
static void ccw_device_call_sch_unregister(struct work_struct *work);
314

Linus Torvalds's avatar
Linus Torvalds committed
315 316 317
static void
ccw_device_remove_disconnected(struct ccw_device *cdev)
{
318
	unsigned long flags;
319

Linus Torvalds's avatar
Linus Torvalds committed
320 321 322 323
	/*
	 * Forced offline in disconnected state means
	 * 'throw away device'.
	 */
324 325 326
	/* Get cdev reference for workqueue processing. */
	if (!get_device(&cdev->dev))
		return;
327
	if (ccw_device_is_orphan(cdev)) {
328 329 330 331 332
		/*
		 * Deregister ccw device.
		 * Unfortunately, we cannot do this directly from the
		 * attribute method.
		 */
333 334 335
		spin_lock_irqsave(cdev->ccwlock, flags);
		cdev->private->state = DEV_STATE_NOT_OPER;
		spin_unlock_irqrestore(cdev->ccwlock, flags);
336 337 338 339 340 341 342
		PREPARE_WORK(&cdev->private->kick_work,
				ccw_device_remove_orphan_cb);
	} else
		/* Deregister subchannel, which will kill the ccw device. */
		PREPARE_WORK(&cdev->private->kick_work,
				ccw_device_call_sch_unregister);
	queue_work(slow_path_wq, &cdev->private->kick_work);
Linus Torvalds's avatar
Linus Torvalds committed
343 344
}

345 346 347 348 349 350 351 352 353 354 355 356
/**
 * ccw_device_set_offline() - disable a ccw device for I/O
 * @cdev: target ccw device
 *
 * This function calls the driver's set_offline() function for @cdev, if
 * given, and then disables @cdev.
 * Returns:
 *   %0 on success and a negative error value on failure.
 * Context:
 *  enabled, ccw device lock not held
 */
int ccw_device_set_offline(struct ccw_device *cdev)
Linus Torvalds's avatar
Linus Torvalds committed
357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378
{
	int ret;

	if (!cdev)
		return -ENODEV;
	if (!cdev->online || !cdev->drv)
		return -EINVAL;

	if (cdev->drv->set_offline) {
		ret = cdev->drv->set_offline(cdev);
		if (ret != 0)
			return ret;
	}
	cdev->online = 0;
	spin_lock_irq(cdev->ccwlock);
	ret = ccw_device_offline(cdev);
	if (ret == -ENODEV) {
		if (cdev->private->state != DEV_STATE_NOT_OPER) {
			cdev->private->state = DEV_STATE_OFFLINE;
			dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
		}
		spin_unlock_irq(cdev->ccwlock);
379 380
		/* Give up reference from ccw_device_set_online(). */
		put_device(&cdev->dev);
Linus Torvalds's avatar
Linus Torvalds committed
381 382 383
		return ret;
	}
	spin_unlock_irq(cdev->ccwlock);
384
	if (ret == 0) {
Linus Torvalds's avatar
Linus Torvalds committed
385
		wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
386 387 388
		/* Give up reference from ccw_device_set_online(). */
		put_device(&cdev->dev);
	} else {
389
		CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
Cornelia Huck's avatar
Cornelia Huck committed
390 391 392
			      "device 0.%x.%04x\n",
			      ret, cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno);
Linus Torvalds's avatar
Linus Torvalds committed
393 394
		cdev->online = 1;
	}
395
	return ret;
Linus Torvalds's avatar
Linus Torvalds committed
396 397
}

398 399 400 401 402 403 404 405 406 407 408 409 410
/**
 * ccw_device_set_online() - enable a ccw device for I/O
 * @cdev: target ccw device
 *
 * This function first enables @cdev and then calls the driver's set_online()
 * function for @cdev, if given. If set_online() returns an error, @cdev is
 * disabled again.
 * Returns:
 *   %0 on success and a negative error value on failure.
 * Context:
 *  enabled, ccw device lock not held
 */
int ccw_device_set_online(struct ccw_device *cdev)
Linus Torvalds's avatar
Linus Torvalds committed
411 412 413 414 415 416 417
{
	int ret;

	if (!cdev)
		return -ENODEV;
	if (cdev->online || !cdev->drv)
		return -EINVAL;
418 419 420
	/* Hold on to an extra reference while device is online. */
	if (!get_device(&cdev->dev))
		return -ENODEV;
Linus Torvalds's avatar
Linus Torvalds committed
421 422 423 424 425 426 427

	spin_lock_irq(cdev->ccwlock);
	ret = ccw_device_online(cdev);
	spin_unlock_irq(cdev->ccwlock);
	if (ret == 0)
		wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
	else {
428
		CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
Cornelia Huck's avatar
Cornelia Huck committed
429 430 431
			      "device 0.%x.%04x\n",
			      ret, cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno);
432 433
		/* Give up online reference since onlining failed. */
		put_device(&cdev->dev);
Linus Torvalds's avatar
Linus Torvalds committed
434 435
		return ret;
	}
436 437 438
	if (cdev->private->state != DEV_STATE_ONLINE) {
		/* Give up online reference since onlining failed. */
		put_device(&cdev->dev);
Linus Torvalds's avatar
Linus Torvalds committed
439
		return -ENODEV;
440
	}
Linus Torvalds's avatar
Linus Torvalds committed
441 442 443 444 445 446 447 448 449
	if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
		cdev->online = 1;
		return 0;
	}
	spin_lock_irq(cdev->ccwlock);
	ret = ccw_device_offline(cdev);
	spin_unlock_irq(cdev->ccwlock);
	if (ret == 0)
		wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
Cornelia Huck's avatar
Cornelia Huck committed
450
	else
451
		CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
Cornelia Huck's avatar
Cornelia Huck committed
452 453 454
			      "device 0.%x.%04x\n",
			      ret, cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno);
455 456
	/* Give up online reference since onlining failed. */
	put_device(&cdev->dev);
457
	return (ret == 0) ? -ENODEV : ret;
Linus Torvalds's avatar
Linus Torvalds committed
458 459
}

460
static int online_store_handle_offline(struct ccw_device *cdev)
461 462 463
{
	if (cdev->private->state == DEV_STATE_DISCONNECTED)
		ccw_device_remove_disconnected(cdev);
464 465 466
	else if (cdev->online && cdev->drv && cdev->drv->set_offline)
		return ccw_device_set_offline(cdev);
	return 0;
467 468 469 470 471 472 473 474 475 476
}

static int online_store_recog_and_online(struct ccw_device *cdev)
{
	int ret;

	/* Do device recognition, if needed. */
	if (cdev->id.cu_type == 0) {
		ret = ccw_device_recognition(cdev);
		if (ret) {
Cornelia Huck's avatar
Cornelia Huck committed
477 478 479 480
			CIO_MSG_EVENT(0, "Couldn't start recognition "
				      "for device 0.%x.%04x (ret=%d)\n",
				      cdev->private->dev_id.ssid,
				      cdev->private->dev_id.devno, ret);
481 482 483 484 485 486 487 488 489
			return ret;
		}
		wait_event(cdev->private->wait_q,
			   cdev->private->flags.recog_done);
	}
	if (cdev->drv && cdev->drv->set_online)
		ccw_device_set_online(cdev);
	return 0;
}
490
static int online_store_handle_online(struct ccw_device *cdev, int force)
491 492 493 494 495
{
	int ret;

	ret = online_store_recog_and_online(cdev);
	if (ret)
496
		return ret;
497 498
	if (force && cdev->private->state == DEV_STATE_BOXED) {
		ret = ccw_device_stlck(cdev);
499 500
		if (ret)
			return ret;
501 502 503 504
		if (cdev->id.cu_type == 0)
			cdev->private->state = DEV_STATE_NOT_OPER;
		online_store_recog_and_online(cdev);
	}
505
	return 0;
506 507 508 509
}

static ssize_t online_store (struct device *dev, struct device_attribute *attr,
			     const char *buf, size_t count)
Linus Torvalds's avatar
Linus Torvalds committed
510 511
{
	struct ccw_device *cdev = to_ccwdev(dev);
512 513
	int force, ret;
	unsigned long i;
Linus Torvalds's avatar
Linus Torvalds committed
514

515
	if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
Linus Torvalds's avatar
Linus Torvalds committed
516 517 518 519 520 521 522 523 524
		return -EAGAIN;

	if (cdev->drv && !try_module_get(cdev->drv->owner)) {
		atomic_set(&cdev->private->onoff, 0);
		return -EINVAL;
	}
	if (!strncmp(buf, "force\n", count)) {
		force = 1;
		i = 1;
525
		ret = 0;
Linus Torvalds's avatar
Linus Torvalds committed
526 527
	} else {
		force = 0;
528
		ret = strict_strtoul(buf, 16, &i);
Linus Torvalds's avatar
Linus Torvalds committed
529
	}
530 531
	if (ret)
		goto out;
532 533
	switch (i) {
	case 0:
534
		ret = online_store_handle_offline(cdev);
535 536
		break;
	case 1:
537
		ret = online_store_handle_online(cdev, force);
538 539
		break;
	default:
540
		ret = -EINVAL;
Linus Torvalds's avatar
Linus Torvalds committed
541
	}
542
out:
Linus Torvalds's avatar
Linus Torvalds committed
543 544 545
	if (cdev->drv)
		module_put(cdev->drv->owner);
	atomic_set(&cdev->private->onoff, 0);
546
	return (ret < 0) ? ret : count;
Linus Torvalds's avatar
Linus Torvalds committed
547 548 549
}

static ssize_t
550
available_show (struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds's avatar
Linus Torvalds committed
551 552 553 554
{
	struct ccw_device *cdev = to_ccwdev(dev);
	struct subchannel *sch;

555 556
	if (ccw_device_is_orphan(cdev))
		return sprintf(buf, "no device\n");
Linus Torvalds's avatar
Linus Torvalds committed
557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577
	switch (cdev->private->state) {
	case DEV_STATE_BOXED:
		return sprintf(buf, "boxed\n");
	case DEV_STATE_DISCONNECTED:
	case DEV_STATE_DISCONNECTED_SENSE_ID:
	case DEV_STATE_NOT_OPER:
		sch = to_subchannel(dev->parent);
		if (!sch->lpm)
			return sprintf(buf, "no path\n");
		else
			return sprintf(buf, "no device\n");
	default:
		/* All other states considered fine. */
		return sprintf(buf, "good\n");
	}
}

static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
578
static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
Linus Torvalds's avatar
Linus Torvalds committed
579 580 581
static DEVICE_ATTR(online, 0644, online_show, online_store);
static DEVICE_ATTR(availability, 0444, available_show, NULL);

582
static struct attribute *io_subchannel_attrs[] = {
Linus Torvalds's avatar
Linus Torvalds committed
583 584 585 586 587
	&dev_attr_chpids.attr,
	&dev_attr_pimpampom.attr,
	NULL,
};

588 589
static struct attribute_group io_subchannel_attr_group = {
	.attrs = io_subchannel_attrs,
590
};
Linus Torvalds's avatar
Linus Torvalds committed
591 592 593 594

static struct attribute * ccwdev_attrs[] = {
	&dev_attr_devtype.attr,
	&dev_attr_cutype.attr,
595
	&dev_attr_modalias.attr,
Linus Torvalds's avatar
Linus Torvalds committed
596 597 598 599 600 601 602 603 604 605
	&dev_attr_online.attr,
	&dev_attr_cmb_enable.attr,
	&dev_attr_availability.attr,
	NULL,
};

static struct attribute_group ccwdev_attr_group = {
	.attrs = ccwdev_attrs,
};

606
static struct attribute_group *ccwdev_attr_groups[] = {
607 608 609
	&ccwdev_attr_group,
	NULL,
};
Linus Torvalds's avatar
Linus Torvalds committed
610 611 612

/* this is a simple abstraction for device_register that sets the
 * correct bus type and adds the bus specific files */
613
static int ccw_device_register(struct ccw_device *cdev)
Linus Torvalds's avatar
Linus Torvalds committed
614 615 616 617 618 619 620 621 622 623 624 625 626
{
	struct device *dev = &cdev->dev;
	int ret;

	dev->bus = &ccw_bus_type;

	if ((ret = device_add(dev)))
		return ret;

	set_bit(1, &cdev->private->registered);
	return ret;
}

627
struct match_data {
628
	struct ccw_dev_id dev_id;
629 630 631 632 633 634
	struct ccw_device * sibling;
};

static int
match_devno(struct device * dev, void * data)
{
635
	struct match_data * d = data;
636 637 638 639
	struct ccw_device * cdev;

	cdev = to_ccwdev(dev);
	if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
640
	    !ccw_device_is_orphan(cdev) &&
641
	    ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
642
	    (cdev != d->sibling))
643 644 645 646
		return 1;
	return 0;
}

647 648
static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
						     struct ccw_device *sibling)
Linus Torvalds's avatar
Linus Torvalds committed
649 650
{
	struct device *dev;
651
	struct match_data data;
Linus Torvalds's avatar
Linus Torvalds committed
652

653
	data.dev_id = *dev_id;
654
	data.sibling = sibling;
655
	dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
Linus Torvalds's avatar
Linus Torvalds committed
656

657
	return dev ? to_ccwdev(dev) : NULL;
Linus Torvalds's avatar
Linus Torvalds committed
658 659
}

660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681
static int match_orphan(struct device *dev, void *data)
{
	struct ccw_dev_id *dev_id;
	struct ccw_device *cdev;

	dev_id = data;
	cdev = to_ccwdev(dev);
	return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
}

static struct ccw_device *
get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
			      struct ccw_dev_id *dev_id)
{
	struct device *dev;

	dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
				match_orphan);

	return dev ? to_ccwdev(dev) : NULL;
}

682
void ccw_device_do_unbind_bind(struct work_struct *work)
Linus Torvalds's avatar
Linus Torvalds committed
683
{
684
	struct ccw_device_private *priv;
Linus Torvalds's avatar
Linus Torvalds committed
685 686
	struct ccw_device *cdev;
	struct subchannel *sch;
687
	int ret;
Linus Torvalds's avatar
Linus Torvalds committed
688

689 690
	priv = container_of(work, struct ccw_device_private, kick_work);
	cdev = priv->cdev;
Linus Torvalds's avatar
Linus Torvalds committed
691
	sch = to_subchannel(cdev->dev.parent);
692

693 694 695 696 697
	if (test_bit(1, &cdev->private->registered)) {
		device_release_driver(&cdev->dev);
		ret = device_attach(&cdev->dev);
		WARN_ON(ret == -ENODEV);
	}
Linus Torvalds's avatar
Linus Torvalds committed
698 699 700 701 702 703 704 705
}

static void
ccw_device_release(struct device *dev)
{
	struct ccw_device *cdev;

	cdev = to_ccwdev(dev);
706 707
	/* Release reference of parent subchannel. */
	put_device(cdev->dev.parent);
Linus Torvalds's avatar
Linus Torvalds committed
708 709 710 711
	kfree(cdev->private);
	kfree(cdev);
}

712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733
static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
{
	struct ccw_device *cdev;

	cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
	if (cdev) {
		cdev->private = kzalloc(sizeof(struct ccw_device_private),
					GFP_KERNEL | GFP_DMA);
		if (cdev->private)
			return cdev;
	}
	kfree(cdev);
	return ERR_PTR(-ENOMEM);
}

static int io_subchannel_initialize_dev(struct subchannel *sch,
					struct ccw_device *cdev)
{
	cdev->private->cdev = cdev;
	atomic_set(&cdev->private->onoff, 0);
	cdev->dev.parent = &sch->dev;
	cdev->dev.release = ccw_device_release;
734
	INIT_WORK(&cdev->private->kick_work, NULL);
735
	cdev->dev.groups = ccwdev_attr_groups;
736 737 738
	/* Do first half of device_register. */
	device_initialize(&cdev->dev);
	if (!get_device(&sch->dev)) {
739 740
		/* Release reference from device_initialize(). */
		put_device(&cdev->dev);
741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761
		return -ENODEV;
	}
	return 0;
}

static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
{
	struct ccw_device *cdev;
	int ret;

	cdev = io_subchannel_allocate_dev(sch);
	if (!IS_ERR(cdev)) {
		ret = io_subchannel_initialize_dev(sch, cdev);
		if (ret) {
			kfree(cdev);
			cdev = ERR_PTR(ret);
		}
	}
	return cdev;
}

762 763 764 765 766
static int io_subchannel_recog(struct ccw_device *, struct subchannel *);

static void sch_attach_device(struct subchannel *sch,
			      struct ccw_device *cdev)
{
767
	css_update_ssd_info(sch);
768
	spin_lock_irq(sch->lock);
769
	sch_set_cdev(sch, cdev);
770 771
	cdev->private->schid = sch->schid;
	cdev->ccwlock = sch->lock;
Cornelia Huck's avatar
Cornelia Huck committed
772
	ccw_device_trigger_reprobe(cdev);
773 774 775 776 777 778 779 780 781
	spin_unlock_irq(sch->lock);
}

static void sch_attach_disconnected_device(struct subchannel *sch,
					   struct ccw_device *cdev)
{
	struct subchannel *other_sch;
	int ret;

782 783 784 785 786
	/* Get reference for new parent. */
	if (!get_device(&sch->dev))
		return;
	other_sch = to_subchannel(cdev->dev.parent);
	/* Note: device_move() changes cdev->dev.parent */
787
	ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
788
	if (ret) {
789
		CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
790 791
			      "(ret=%d)!\n", cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno, ret);
792 793
		/* Put reference for new parent. */
		put_device(&sch->dev);
794 795
		return;
	}
796
	sch_set_cdev(other_sch, NULL);
797 798 799
	/* No need to keep a subchannel without ccw device around. */
	css_sch_device_unregister(other_sch);
	sch_attach_device(sch, cdev);
800 801
	/* Put reference for old parent. */
	put_device(&other_sch->dev);
802 803 804 805 806 807
}

static void sch_attach_orphaned_device(struct subchannel *sch,
				       struct ccw_device *cdev)
{
	int ret;
808
	struct subchannel *pseudo_sch;
809

810 811 812 813 814 815 816 817
	/* Get reference for new parent. */
	if (!get_device(&sch->dev))
		return;
	pseudo_sch = to_subchannel(cdev->dev.parent);
	/*
	 * Try to move the ccw device to its new subchannel.
	 * Note: device_move() changes cdev->dev.parent
	 */
818
	ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
819 820 821 822 823
	if (ret) {
		CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
			      "failed (ret=%d)!\n",
			      cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno, ret);
824 825
		/* Put reference for new parent. */
		put_device(&sch->dev);
826 827 828
		return;
	}
	sch_attach_device(sch, cdev);
829 830
	/* Put reference on pseudo subchannel. */
	put_device(&pseudo_sch->dev);
831 832 833 834 835 836 837 838 839 840 841 842 843 844
}

static void sch_create_and_recog_new_device(struct subchannel *sch)
{
	struct ccw_device *cdev;

	/* Need to allocate a new ccw device. */
	cdev = io_subchannel_create_ccwdev(sch);
	if (IS_ERR(cdev)) {
		/* OK, we did everything we could... */
		css_sch_device_unregister(sch);
		return;
	}
	spin_lock_irq(sch->lock);
845
	sch_set_cdev(sch, cdev);
846 847 848 849
	spin_unlock_irq(sch->lock);
	/* Start recognition for the new ccw device. */
	if (io_subchannel_recog(cdev, sch)) {
		spin_lock_irq(sch->lock);
850
		sch_set_cdev(sch, NULL);
851 852
		spin_unlock_irq(sch->lock);
		css_sch_device_unregister(sch);
853 854 855 856
		/* Put reference from io_subchannel_create_ccwdev(). */
		put_device(&sch->dev);
		/* Give up initial reference. */
		put_device(&cdev->dev);
857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877
	}
}


void ccw_device_move_to_orphanage(struct work_struct *work)
{
	struct ccw_device_private *priv;
	struct ccw_device *cdev;
	struct ccw_device *replacing_cdev;
	struct subchannel *sch;
	int ret;
	struct channel_subsystem *css;
	struct ccw_dev_id dev_id;

	priv = container_of(work, struct ccw_device_private, kick_work);
	cdev = priv->cdev;
	sch = to_subchannel(cdev->dev.parent);
	css = to_css(sch->dev.parent);
	dev_id.devno = sch->schib.pmcw.dev;
	dev_id.ssid = sch->schid.ssid;

878 879
	/* Increase refcount for pseudo subchannel. */
	get_device(&css->pseudo_subchannel->dev);
880 881 882
	/*
	 * Move the orphaned ccw device to the orphanage so the replacing
	 * ccw device can take its place on the subchannel.
883
	 * Note: device_move() changes cdev->dev.parent
884
	 */
885 886
	ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev,
		DPM_ORDER_NONE);
887 888 889 890
	if (ret) {
		CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
			      "(ret=%d)!\n", cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno, ret);
891 892
		/* Decrease refcount for pseudo subchannel again. */
		put_device(&css->pseudo_subchannel->dev);
893 894 895 896 897 898 899 900 901 902 903
		return;
	}
	cdev->ccwlock = css->pseudo_subchannel->lock;
	/*
	 * Search for the replacing ccw device
	 * - among the disconnected devices
	 * - in the orphanage
	 */
	replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
	if (replacing_cdev) {
		sch_attach_disconnected_device(sch, replacing_cdev);
904
		/* Release reference from get_disc_ccwdev_by_dev_id() */
905
		put_device(&replacing_cdev->dev);
906 907
		/* Release reference of subchannel from old cdev. */
		put_device(&sch->dev);
908 909 910 911 912
		return;
	}
	replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
	if (replacing_cdev) {
		sch_attach_orphaned_device(sch, replacing_cdev);
913
		/* Release reference from get_orphaned_ccwdev_by_dev_id() */
914
		put_device(&replacing_cdev->dev);
915 916
		/* Release reference of subchannel from old cdev. */
		put_device(&sch->dev);
917 918 919
		return;
	}
	sch_create_and_recog_new_device(sch);
920 921
	/* Release reference of subchannel from old cdev. */
	put_device(&sch->dev);
922 923
}

Linus Torvalds's avatar
Linus Torvalds committed
924 925 926 927
/*
 * Register recognized device.
 */
static void
928
io_subchannel_register(struct work_struct *work)
Linus Torvalds's avatar
Linus Torvalds committed
929
{
930
	struct ccw_device_private *priv;
Linus Torvalds's avatar
Linus Torvalds committed
931 932 933 934 935
	struct ccw_device *cdev;
	struct subchannel *sch;
	int ret;
	unsigned long flags;

936 937
	priv = container_of(work, struct ccw_device_private, kick_work);
	cdev = priv->cdev;
Linus Torvalds's avatar
Linus Torvalds committed
938
	sch = to_subchannel(cdev->dev.parent);
939 940 941 942 943 944 945 946
	/*
	 * Check if subchannel is still registered. It may have become
	 * unregistered if a machine check hit us after finishing
	 * device recognition but before the register work could be
	 * queued.
	 */
	if (!device_is_registered(&sch->dev))
		goto out_err;
947
	css_update_ssd_info(sch);
948 949 950 951 952 953
	/*
	 * io_subchannel_register() will also be called after device
	 * recognition has been done for a boxed device (which will already
	 * be registered). We need to reprobe since we may now have sense id
	 * information.
	 */
954
	if (device_is_registered(&cdev->dev)) {
955 956 957 958
		if (!cdev->drv) {
			ret = device_reprobe(&cdev->dev);
			if (ret)
				/* We can't do much here. */
959
				CIO_MSG_EVENT(0, "device_reprobe() returned"
Cornelia Huck's avatar
Cornelia Huck committed
960 961 962
					      " %d for 0.%x.%04x\n", ret,
					      cdev->private->dev_id.ssid,
					      cdev->private->dev_id.devno);
963
		}
Linus Torvalds's avatar
Linus Torvalds committed
964 965
		goto out;
	}
966 967 968 969
	/*
	 * Now we know this subchannel will stay, we can throw
	 * our delayed uevent.
	 */
970
	dev_set_uevent_suppress(&sch->dev, 0);
971
	kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
Linus Torvalds's avatar
Linus Torvalds committed
972 973 974
	/* make it known to the system */
	ret = ccw_device_register(cdev);
	if (ret) {
Cornelia Huck's avatar
Cornelia Huck committed
975 976 977
		CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
			      cdev->private->dev_id.ssid,
			      cdev->private->dev_id.devno, ret);
978
		spin_lock_irqsave(sch->lock, flags);
979
		sch_set_cdev(sch, NULL);
980
		spin_unlock_irqrestore(sch->lock, flags);
981 982
		/* Release initial device reference. */
		put_device(&cdev->dev);
983
		goto out_err;
Linus Torvalds's avatar
Linus Torvalds committed
984 985 986 987
	}
out:
	cdev->private->flags.recog_done = 1;
	wake_up(&cdev->private->wait_q);
988 989 990
out_err:
	/* Release reference for workqueue processing. */
	put_device(&cdev->dev);
Linus Torvalds's avatar
Linus Torvalds committed
991 992 993 994
	if (atomic_dec_and_test(&ccw_device_init_count))
		wake_up(&ccw_device_init_wq);
}

995
static void ccw_device_call_sch_unregister(struct work_struct *work)
Linus Torvalds's avatar
Linus Torvalds committed
996
{
997 998
	struct ccw_device_private *priv;
	struct ccw_device *cdev;
Linus Torvalds's avatar
Linus Torvalds committed
999 1000
	struct subchannel *sch;

1001 1002
	priv = container_of(work, struct ccw_device_private, kick_work);
	cdev = priv->cdev;
1003 1004 1005
	/* Get subchannel reference for local processing. */
	if (!get_device(cdev->dev.parent))
		return;
Linus Torvalds's avatar
Linus Torvalds committed
1006
	sch = to_subchannel(cdev->dev.parent);
1007
	css_sch_device_unregister(sch);
Linus Torvalds's avatar
Linus Torvalds committed
1008
	/* Reset intparm to zeroes. */
1009 1010
	sch->config.intparm = 0;
	cio_commit_config(sch);
1011
	/* Release cdev reference for workqueue processing.*/
Linus Torvalds's avatar
Linus Torvalds committed
1012
	put_device(&cdev->dev);
1013
	/* Release subchannel reference for local processing. */
Linus Torvalds's avatar
Linus Torvalds committed
1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033
	put_device(&sch->dev);
}

/*
 * subchannel recognition done. Called from the state machine.
 */
void
io_subchannel_recog_done(struct ccw_device *cdev)
{
	if (css_init_done == 0) {
		cdev->private->flags.recog_done = 1;
		return;
	}
	switch (cdev->private->state) {
	case DEV_STATE_NOT_OPER:
		cdev->private->flags.recog_done = 1;
		/* Remove device found not operational. */
		if (!get_device(&cdev->dev))
			break;
		PREPARE_WORK(&cdev->private->kick_work,
1034
			     ccw_device_call_sch_unregister);
Linus Torvalds's avatar
Linus Torvalds committed
1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048
		queue_work(slow_path_wq, &cdev->private->kick_work);
		if (atomic_dec_and_test(&ccw_device_init_count))
			wake_up(&ccw_device_init_wq);
		break;
	case DEV_STATE_BOXED:
		/* Device did not respond in time. */
	case DEV_STATE_OFFLINE:
		/* 
		 * We can't register the device in interrupt context so
		 * we schedule a work item.
		 */
		if (!get_device(&cdev->dev))
			break;
		PREPARE_WORK(&cdev->private->kick_work,
1049
			     io_subchannel_register);
Linus Torvalds's avatar
Linus Torvalds committed
1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060
		queue_work(slow_path_wq, &cdev->private->kick_work);
		break;
	}
}

static int
io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
{
	int rc;
	struct ccw_device_private *priv;

1061
	sch_set_cdev(sch, cdev);
1062