xref: /linux/drivers/s390/cio/device_ops.c (revision b454cc6636d254fbf6049b73e9560aee76fb04a3)
1 /*
2  *  drivers/s390/cio/device_ops.c
3  *
4  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
5  *			 IBM Corporation
6  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
7  *               Cornelia Huck (cornelia.huck@de.ibm.com)
8  */
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/slab.h>
13 #include <linux/list.h>
14 #include <linux/device.h>
15 #include <linux/delay.h>
16 
17 #include <asm/ccwdev.h>
18 #include <asm/idals.h>
19 
20 #include "cio.h"
21 #include "cio_debug.h"
22 #include "css.h"
23 #include "chsc.h"
24 #include "device.h"
25 
26 int
27 ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
28 {
29        /*
30 	* The flag usage is mutal exclusive ...
31 	*/
32 	if ((flags & CCWDEV_EARLY_NOTIFICATION) &&
33 	    (flags & CCWDEV_REPORT_ALL))
34 		return -EINVAL;
35 	cdev->private->options.fast = (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
36 	cdev->private->options.repall = (flags & CCWDEV_REPORT_ALL) != 0;
37 	cdev->private->options.pgroup = (flags & CCWDEV_DO_PATHGROUP) != 0;
38 	cdev->private->options.force = (flags & CCWDEV_ALLOW_FORCE) != 0;
39 	return 0;
40 }
41 
42 int
43 ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
44 {
45 	struct subchannel *sch;
46 	int ret;
47 
48 	if (!cdev)
49 		return -ENODEV;
50 	if (cdev->private->state == DEV_STATE_NOT_OPER)
51 		return -ENODEV;
52 	if (cdev->private->state != DEV_STATE_ONLINE &&
53 	    cdev->private->state != DEV_STATE_W4SENSE)
54 		return -EINVAL;
55 	sch = to_subchannel(cdev->dev.parent);
56 	if (!sch)
57 		return -ENODEV;
58 	ret = cio_clear(sch);
59 	if (ret == 0)
60 		cdev->private->intparm = intparm;
61 	return ret;
62 }
63 
64 int
65 ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
66 		     unsigned long intparm, __u8 lpm, __u8 key,
67 		     unsigned long flags)
68 {
69 	struct subchannel *sch;
70 	int ret;
71 
72 	if (!cdev)
73 		return -ENODEV;
74 	sch = to_subchannel(cdev->dev.parent);
75 	if (!sch)
76 		return -ENODEV;
77 	if (cdev->private->state == DEV_STATE_NOT_OPER)
78 		return -ENODEV;
79 	if (cdev->private->state == DEV_STATE_VERIFY ||
80 	    cdev->private->state == DEV_STATE_CLEAR_VERIFY) {
81 		/* Remember to fake irb when finished. */
82 		if (!cdev->private->flags.fake_irb) {
83 			cdev->private->flags.fake_irb = 1;
84 			cdev->private->intparm = intparm;
85 			return 0;
86 		} else
87 			/* There's already a fake I/O around. */
88 			return -EBUSY;
89 	}
90 	if (cdev->private->state != DEV_STATE_ONLINE ||
91 	    ((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
92 	     !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
93 	    cdev->private->flags.doverify)
94 		return -EBUSY;
95 	ret = cio_set_options (sch, flags);
96 	if (ret)
97 		return ret;
98 	/* Adjust requested path mask to excluded varied off paths. */
99 	if (lpm) {
100 		lpm &= sch->opm;
101 		if (lpm == 0)
102 			return -EACCES;
103 	}
104 	ret = cio_start_key (sch, cpa, lpm, key);
105 	if (ret == 0)
106 		cdev->private->intparm = intparm;
107 	return ret;
108 }
109 
110 
111 int
112 ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
113 			     unsigned long intparm, __u8 lpm, __u8 key,
114 			     unsigned long flags, int expires)
115 {
116 	int ret;
117 
118 	if (!cdev)
119 		return -ENODEV;
120 	ccw_device_set_timeout(cdev, expires);
121 	ret = ccw_device_start_key(cdev, cpa, intparm, lpm, key, flags);
122 	if (ret != 0)
123 		ccw_device_set_timeout(cdev, 0);
124 	return ret;
125 }
126 
127 int
128 ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
129 		 unsigned long intparm, __u8 lpm, unsigned long flags)
130 {
131 	return ccw_device_start_key(cdev, cpa, intparm, lpm,
132 				    PAGE_DEFAULT_KEY, flags);
133 }
134 
135 int
136 ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
137 			 unsigned long intparm, __u8 lpm, unsigned long flags,
138 			 int expires)
139 {
140 	return ccw_device_start_timeout_key(cdev, cpa, intparm, lpm,
141 					    PAGE_DEFAULT_KEY, flags,
142 					    expires);
143 }
144 
145 
146 int
147 ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
148 {
149 	struct subchannel *sch;
150 	int ret;
151 
152 	if (!cdev)
153 		return -ENODEV;
154 	if (cdev->private->state == DEV_STATE_NOT_OPER)
155 		return -ENODEV;
156 	if (cdev->private->state != DEV_STATE_ONLINE &&
157 	    cdev->private->state != DEV_STATE_W4SENSE)
158 		return -EINVAL;
159 	sch = to_subchannel(cdev->dev.parent);
160 	if (!sch)
161 		return -ENODEV;
162 	ret = cio_halt(sch);
163 	if (ret == 0)
164 		cdev->private->intparm = intparm;
165 	return ret;
166 }
167 
168 int
169 ccw_device_resume(struct ccw_device *cdev)
170 {
171 	struct subchannel *sch;
172 
173 	if (!cdev)
174 		return -ENODEV;
175 	sch = to_subchannel(cdev->dev.parent);
176 	if (!sch)
177 		return -ENODEV;
178 	if (cdev->private->state == DEV_STATE_NOT_OPER)
179 		return -ENODEV;
180 	if (cdev->private->state != DEV_STATE_ONLINE ||
181 	    !(sch->schib.scsw.actl & SCSW_ACTL_SUSPENDED))
182 		return -EINVAL;
183 	return cio_resume(sch);
184 }
185 
186 /*
187  * Pass interrupt to device driver.
188  */
189 int
190 ccw_device_call_handler(struct ccw_device *cdev)
191 {
192 	struct subchannel *sch;
193 	unsigned int stctl;
194 	int ending_status;
195 
196 	sch = to_subchannel(cdev->dev.parent);
197 
198 	/*
199 	 * we allow for the device action handler if .
200 	 *  - we received ending status
201 	 *  - the action handler requested to see all interrupts
202 	 *  - we received an intermediate status
203 	 *  - fast notification was requested (primary status)
204 	 *  - unsolicited interrupts
205 	 */
206 	stctl = cdev->private->irb.scsw.stctl;
207 	ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
208 		(stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
209 		(stctl == SCSW_STCTL_STATUS_PEND);
210 	if (!ending_status &&
211 	    !cdev->private->options.repall &&
212 	    !(stctl & SCSW_STCTL_INTER_STATUS) &&
213 	    !(cdev->private->options.fast &&
214 	      (stctl & SCSW_STCTL_PRIM_STATUS)))
215 		return 0;
216 
217 	/* Clear pending timers for device driver initiated I/O. */
218 	if (ending_status)
219 		ccw_device_set_timeout(cdev, 0);
220 	/*
221 	 * Now we are ready to call the device driver interrupt handler.
222 	 */
223 	if (cdev->handler)
224 		cdev->handler(cdev, cdev->private->intparm,
225 			      &cdev->private->irb);
226 
227 	/*
228 	 * Clear the old and now useless interrupt response block.
229 	 */
230 	memset(&cdev->private->irb, 0, sizeof(struct irb));
231 
232 	return 1;
233 }
234 
235 /*
236  * Search for CIW command in extended sense data.
237  */
238 struct ciw *
239 ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
240 {
241 	int ciw_cnt;
242 
243 	if (cdev->private->flags.esid == 0)
244 		return NULL;
245 	for (ciw_cnt = 0; ciw_cnt < MAX_CIWS; ciw_cnt++)
246 		if (cdev->private->senseid.ciw[ciw_cnt].ct == ct)
247 			return cdev->private->senseid.ciw + ciw_cnt;
248 	return NULL;
249 }
250 
251 __u8
252 ccw_device_get_path_mask(struct ccw_device *cdev)
253 {
254 	struct subchannel *sch;
255 
256 	sch = to_subchannel(cdev->dev.parent);
257 	if (!sch)
258 		return 0;
259 	else
260 		return sch->lpm;
261 }
262 
263 static void
264 ccw_device_wake_up(struct ccw_device *cdev, unsigned long ip, struct irb *irb)
265 {
266 	if (!ip)
267 		/* unsolicited interrupt */
268 		return;
269 
270 	/* Abuse intparm for error reporting. */
271 	if (IS_ERR(irb))
272 		cdev->private->intparm = -EIO;
273 	else if (irb->scsw.cc == 1)
274 		/* Retry for deferred condition code. */
275 		cdev->private->intparm = -EAGAIN;
276 	else if ((irb->scsw.dstat !=
277 		  (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
278 		 (irb->scsw.cstat != 0)) {
279 		/*
280 		 * We didn't get channel end / device end. Check if path
281 		 * verification has been started; we can retry after it has
282 		 * finished. We also retry unit checks except for command reject
283 		 * or intervention required. Also check for long busy
284 		 * conditions.
285 		 */
286 		 if (cdev->private->flags.doverify ||
287 			 cdev->private->state == DEV_STATE_VERIFY)
288 			 cdev->private->intparm = -EAGAIN;
289 		else if ((irb->scsw.dstat & DEV_STAT_UNIT_CHECK) &&
290 			 !(irb->ecw[0] &
291 			   (SNS0_CMD_REJECT | SNS0_INTERVENTION_REQ)))
292 			cdev->private->intparm = -EAGAIN;
293 		else if ((irb->scsw.dstat & DEV_STAT_ATTENTION) &&
294 			 (irb->scsw.dstat & DEV_STAT_DEV_END) &&
295 			 (irb->scsw.dstat & DEV_STAT_UNIT_EXCEP))
296 			cdev->private->intparm = -EAGAIN;
297 		 else
298 			 cdev->private->intparm = -EIO;
299 
300 	} else
301 		cdev->private->intparm = 0;
302 	wake_up(&cdev->private->wait_q);
303 }
304 
305 static int
306 __ccw_device_retry_loop(struct ccw_device *cdev, struct ccw1 *ccw, long magic, __u8 lpm)
307 {
308 	int ret;
309 	struct subchannel *sch;
310 
311 	sch = to_subchannel(cdev->dev.parent);
312 	do {
313 		ccw_device_set_timeout(cdev, 60 * HZ);
314 		ret = cio_start (sch, ccw, lpm);
315 		if (ret != 0)
316 			ccw_device_set_timeout(cdev, 0);
317 		if (ret == -EBUSY) {
318 			/* Try again later. */
319 			spin_unlock_irq(sch->lock);
320 			msleep(10);
321 			spin_lock_irq(sch->lock);
322 			continue;
323 		}
324 		if (ret != 0)
325 			/* Non-retryable error. */
326 			break;
327 		/* Wait for end of request. */
328 		cdev->private->intparm = magic;
329 		spin_unlock_irq(sch->lock);
330 		wait_event(cdev->private->wait_q,
331 			   (cdev->private->intparm == -EIO) ||
332 			   (cdev->private->intparm == -EAGAIN) ||
333 			   (cdev->private->intparm == 0));
334 		spin_lock_irq(sch->lock);
335 		/* Check at least for channel end / device end */
336 		if (cdev->private->intparm == -EIO) {
337 			/* Non-retryable error. */
338 			ret = -EIO;
339 			break;
340 		}
341 		if (cdev->private->intparm == 0)
342 			/* Success. */
343 			break;
344 		/* Try again later. */
345 		spin_unlock_irq(sch->lock);
346 		msleep(10);
347 		spin_lock_irq(sch->lock);
348 	} while (1);
349 
350 	return ret;
351 }
352 
353 /**
354  * read_dev_chars() - read device characteristics
355  * @param cdev   target ccw device
356  * @param buffer pointer to buffer for rdc data
357  * @param length size of rdc data
358  * @returns 0 for success, negative error value on failure
359  *
360  * Context:
361  *   called for online device, lock not held
362  **/
363 int
364 read_dev_chars (struct ccw_device *cdev, void **buffer, int length)
365 {
366 	void (*handler)(struct ccw_device *, unsigned long, struct irb *);
367 	struct subchannel *sch;
368 	int ret;
369 	struct ccw1 *rdc_ccw;
370 
371 	if (!cdev)
372 		return -ENODEV;
373 	if (!buffer || !length)
374 		return -EINVAL;
375 	sch = to_subchannel(cdev->dev.parent);
376 
377 	CIO_TRACE_EVENT (4, "rddevch");
378 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
379 
380 	rdc_ccw = kzalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
381 	if (!rdc_ccw)
382 		return -ENOMEM;
383 	rdc_ccw->cmd_code = CCW_CMD_RDC;
384 	rdc_ccw->count = length;
385 	rdc_ccw->flags = CCW_FLAG_SLI;
386 	ret = set_normalized_cda (rdc_ccw, (*buffer));
387 	if (ret != 0) {
388 		kfree(rdc_ccw);
389 		return ret;
390 	}
391 
392 	spin_lock_irq(sch->lock);
393 	/* Save interrupt handler. */
394 	handler = cdev->handler;
395 	/* Temporarily install own handler. */
396 	cdev->handler = ccw_device_wake_up;
397 	if (cdev->private->state != DEV_STATE_ONLINE)
398 		ret = -ENODEV;
399 	else if (((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
400 		  !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
401 		 cdev->private->flags.doverify)
402 		ret = -EBUSY;
403 	else
404 		/* 0x00D9C4C3 == ebcdic "RDC" */
405 		ret = __ccw_device_retry_loop(cdev, rdc_ccw, 0x00D9C4C3, 0);
406 
407 	/* Restore interrupt handler. */
408 	cdev->handler = handler;
409 	spin_unlock_irq(sch->lock);
410 
411 	clear_normalized_cda (rdc_ccw);
412 	kfree(rdc_ccw);
413 
414 	return ret;
415 }
416 
417 /*
418  *  Read Configuration data using path mask
419  */
420 int
421 read_conf_data_lpm (struct ccw_device *cdev, void **buffer, int *length, __u8 lpm)
422 {
423 	void (*handler)(struct ccw_device *, unsigned long, struct irb *);
424 	struct subchannel *sch;
425 	struct ciw *ciw;
426 	char *rcd_buf;
427 	int ret;
428 	struct ccw1 *rcd_ccw;
429 
430 	if (!cdev)
431 		return -ENODEV;
432 	if (!buffer || !length)
433 		return -EINVAL;
434 	sch = to_subchannel(cdev->dev.parent);
435 
436 	CIO_TRACE_EVENT (4, "rdconf");
437 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
438 
439 	/*
440 	 * scan for RCD command in extended SenseID data
441 	 */
442 	ciw = ccw_device_get_ciw(cdev, CIW_TYPE_RCD);
443 	if (!ciw || ciw->cmd == 0)
444 		return -EOPNOTSUPP;
445 
446 	/* Adjust requested path mask to excluded varied off paths. */
447 	if (lpm) {
448 		lpm &= sch->opm;
449 		if (lpm == 0)
450 			return -EACCES;
451 	}
452 
453 	rcd_ccw = kzalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
454 	if (!rcd_ccw)
455 		return -ENOMEM;
456 	rcd_buf = kzalloc(ciw->count, GFP_KERNEL | GFP_DMA);
457  	if (!rcd_buf) {
458 		kfree(rcd_ccw);
459 		return -ENOMEM;
460 	}
461 	rcd_ccw->cmd_code = ciw->cmd;
462 	rcd_ccw->cda = (__u32) __pa (rcd_buf);
463 	rcd_ccw->count = ciw->count;
464 	rcd_ccw->flags = CCW_FLAG_SLI;
465 
466 	spin_lock_irq(sch->lock);
467 	/* Save interrupt handler. */
468 	handler = cdev->handler;
469 	/* Temporarily install own handler. */
470 	cdev->handler = ccw_device_wake_up;
471 	if (cdev->private->state != DEV_STATE_ONLINE)
472 		ret = -ENODEV;
473 	else if (((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
474 		  !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
475 		 cdev->private->flags.doverify)
476 		ret = -EBUSY;
477 	else
478 		/* 0x00D9C3C4 == ebcdic "RCD" */
479 		ret = __ccw_device_retry_loop(cdev, rcd_ccw, 0x00D9C3C4, lpm);
480 
481 	/* Restore interrupt handler. */
482 	cdev->handler = handler;
483 	spin_unlock_irq(sch->lock);
484 
485  	/*
486  	 * on success we update the user input parms
487  	 */
488  	if (ret) {
489  		kfree (rcd_buf);
490  		*buffer = NULL;
491  		*length = 0;
492  	} else {
493 		*length = ciw->count;
494 		*buffer = rcd_buf;
495 	}
496 	kfree(rcd_ccw);
497 
498 	return ret;
499 }
500 
501 /*
502  *  Read Configuration data
503  */
504 int
505 read_conf_data (struct ccw_device *cdev, void **buffer, int *length)
506 {
507 	return read_conf_data_lpm (cdev, buffer, length, 0);
508 }
509 
510 /*
511  * Try to break the lock on a boxed device.
512  */
513 int
514 ccw_device_stlck(struct ccw_device *cdev)
515 {
516 	void *buf, *buf2;
517 	unsigned long flags;
518 	struct subchannel *sch;
519 	int ret;
520 
521 	if (!cdev)
522 		return -ENODEV;
523 
524 	if (cdev->drv && !cdev->private->options.force)
525 		return -EINVAL;
526 
527 	sch = to_subchannel(cdev->dev.parent);
528 
529 	CIO_TRACE_EVENT(2, "stl lock");
530 	CIO_TRACE_EVENT(2, cdev->dev.bus_id);
531 
532 	buf = kmalloc(32*sizeof(char), GFP_DMA|GFP_KERNEL);
533 	if (!buf)
534 		return -ENOMEM;
535 	buf2 = kmalloc(32*sizeof(char), GFP_DMA|GFP_KERNEL);
536 	if (!buf2) {
537 		kfree(buf);
538 		return -ENOMEM;
539 	}
540 	spin_lock_irqsave(sch->lock, flags);
541 	ret = cio_enable_subchannel(sch, 3);
542 	if (ret)
543 		goto out_unlock;
544 	/*
545 	 * Setup ccw. We chain an unconditional reserve and a release so we
546 	 * only break the lock.
547 	 */
548 	cdev->private->iccws[0].cmd_code = CCW_CMD_STLCK;
549 	cdev->private->iccws[0].cda = (__u32) __pa(buf);
550 	cdev->private->iccws[0].count = 32;
551 	cdev->private->iccws[0].flags = CCW_FLAG_CC;
552 	cdev->private->iccws[1].cmd_code = CCW_CMD_RELEASE;
553 	cdev->private->iccws[1].cda = (__u32) __pa(buf2);
554 	cdev->private->iccws[1].count = 32;
555 	cdev->private->iccws[1].flags = 0;
556 	ret = cio_start(sch, cdev->private->iccws, 0);
557 	if (ret) {
558 		cio_disable_subchannel(sch); //FIXME: return code?
559 		goto out_unlock;
560 	}
561 	cdev->private->irb.scsw.actl |= SCSW_ACTL_START_PEND;
562 	spin_unlock_irqrestore(sch->lock, flags);
563 	wait_event(cdev->private->wait_q, cdev->private->irb.scsw.actl == 0);
564 	spin_lock_irqsave(sch->lock, flags);
565 	cio_disable_subchannel(sch); //FIXME: return code?
566 	if ((cdev->private->irb.scsw.dstat !=
567 	     (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
568 	    (cdev->private->irb.scsw.cstat != 0))
569 		ret = -EIO;
570 	/* Clear irb. */
571 	memset(&cdev->private->irb, 0, sizeof(struct irb));
572 out_unlock:
573 	kfree(buf);
574 	kfree(buf2);
575 	spin_unlock_irqrestore(sch->lock, flags);
576 	return ret;
577 }
578 
579 void *
580 ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no)
581 {
582 	struct subchannel *sch;
583 
584 	sch = to_subchannel(cdev->dev.parent);
585 	return chsc_get_chp_desc(sch, chp_no);
586 }
587 
588 // FIXME: these have to go:
589 
590 int
591 _ccw_device_get_subchannel_number(struct ccw_device *cdev)
592 {
593 	return cdev->private->schid.sch_no;
594 }
595 
596 int
597 _ccw_device_get_device_number(struct ccw_device *cdev)
598 {
599 	return cdev->private->dev_id.devno;
600 }
601 
602 
603 MODULE_LICENSE("GPL");
604 EXPORT_SYMBOL(ccw_device_set_options);
605 EXPORT_SYMBOL(ccw_device_clear);
606 EXPORT_SYMBOL(ccw_device_halt);
607 EXPORT_SYMBOL(ccw_device_resume);
608 EXPORT_SYMBOL(ccw_device_start_timeout);
609 EXPORT_SYMBOL(ccw_device_start);
610 EXPORT_SYMBOL(ccw_device_start_timeout_key);
611 EXPORT_SYMBOL(ccw_device_start_key);
612 EXPORT_SYMBOL(ccw_device_get_ciw);
613 EXPORT_SYMBOL(ccw_device_get_path_mask);
614 EXPORT_SYMBOL(read_conf_data);
615 EXPORT_SYMBOL(read_dev_chars);
616 EXPORT_SYMBOL(_ccw_device_get_subchannel_number);
617 EXPORT_SYMBOL(_ccw_device_get_device_number);
618 EXPORT_SYMBOL_GPL(ccw_device_get_chp_desc);
619 EXPORT_SYMBOL_GPL(read_conf_data_lpm);
620