xref: /linux/drivers/s390/cio/device_ops.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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/config.h>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/errno.h>
13 #include <linux/slab.h>
14 #include <linux/list.h>
15 #include <linux/device.h>
16 #include <linux/delay.h>
17 
18 #include <asm/ccwdev.h>
19 #include <asm/idals.h>
20 
21 #include "cio.h"
22 #include "cio_debug.h"
23 #include "css.h"
24 #include "chsc.h"
25 #include "device.h"
26 
27 int
28 ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
29 {
30        /*
31 	* The flag usage is mutal exclusive ...
32 	*/
33 	if ((flags & CCWDEV_EARLY_NOTIFICATION) &&
34 	    (flags & CCWDEV_REPORT_ALL))
35 		return -EINVAL;
36 	cdev->private->options.fast = (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
37 	cdev->private->options.repall = (flags & CCWDEV_REPORT_ALL) != 0;
38 	cdev->private->options.pgroup = (flags & CCWDEV_DO_PATHGROUP) != 0;
39 	cdev->private->options.force = (flags & CCWDEV_ALLOW_FORCE) != 0;
40 	return 0;
41 }
42 
43 int
44 ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
45 {
46 	struct subchannel *sch;
47 	int ret;
48 
49 	if (!cdev)
50 		return -ENODEV;
51 	if (cdev->private->state == DEV_STATE_NOT_OPER)
52 		return -ENODEV;
53 	if (cdev->private->state != DEV_STATE_ONLINE &&
54 	    cdev->private->state != DEV_STATE_WAIT4IO &&
55 	    cdev->private->state != DEV_STATE_W4SENSE)
56 		return -EINVAL;
57 	sch = to_subchannel(cdev->dev.parent);
58 	if (!sch)
59 		return -ENODEV;
60 	ret = cio_clear(sch);
61 	if (ret == 0)
62 		cdev->private->intparm = intparm;
63 	return ret;
64 }
65 
66 int
67 ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
68 		     unsigned long intparm, __u8 lpm, __u8 key,
69 		     unsigned long flags)
70 {
71 	struct subchannel *sch;
72 	int ret;
73 
74 	if (!cdev)
75 		return -ENODEV;
76 	sch = to_subchannel(cdev->dev.parent);
77 	if (!sch)
78 		return -ENODEV;
79 	if (cdev->private->state == DEV_STATE_NOT_OPER)
80 		return -ENODEV;
81 	if (cdev->private->state == DEV_STATE_VERIFY ||
82 	    cdev->private->state == DEV_STATE_CLEAR_VERIFY) {
83 		/* Remember to fake irb when finished. */
84 		if (!cdev->private->flags.fake_irb) {
85 			cdev->private->flags.fake_irb = 1;
86 			cdev->private->intparm = intparm;
87 			return 0;
88 		} else
89 			/* There's already a fake I/O around. */
90 			return -EBUSY;
91 	}
92 	if (cdev->private->state != DEV_STATE_ONLINE ||
93 	    ((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
94 	     !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
95 	    cdev->private->flags.doverify)
96 		return -EBUSY;
97 	ret = cio_set_options (sch, flags);
98 	if (ret)
99 		return ret;
100 	ret = cio_start_key (sch, cpa, lpm, key);
101 	if (ret == 0)
102 		cdev->private->intparm = intparm;
103 	return ret;
104 }
105 
106 
107 int
108 ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
109 			     unsigned long intparm, __u8 lpm, __u8 key,
110 			     unsigned long flags, int expires)
111 {
112 	int ret;
113 
114 	if (!cdev)
115 		return -ENODEV;
116 	ccw_device_set_timeout(cdev, expires);
117 	ret = ccw_device_start_key(cdev, cpa, intparm, lpm, key, flags);
118 	if (ret != 0)
119 		ccw_device_set_timeout(cdev, 0);
120 	return ret;
121 }
122 
123 int
124 ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
125 		 unsigned long intparm, __u8 lpm, unsigned long flags)
126 {
127 	return ccw_device_start_key(cdev, cpa, intparm, lpm,
128 				    PAGE_DEFAULT_KEY, flags);
129 }
130 
131 int
132 ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
133 			 unsigned long intparm, __u8 lpm, unsigned long flags,
134 			 int expires)
135 {
136 	return ccw_device_start_timeout_key(cdev, cpa, intparm, lpm,
137 					    PAGE_DEFAULT_KEY, flags,
138 					    expires);
139 }
140 
141 
142 int
143 ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
144 {
145 	struct subchannel *sch;
146 	int ret;
147 
148 	if (!cdev)
149 		return -ENODEV;
150 	if (cdev->private->state == DEV_STATE_NOT_OPER)
151 		return -ENODEV;
152 	if (cdev->private->state != DEV_STATE_ONLINE &&
153 	    cdev->private->state != DEV_STATE_WAIT4IO &&
154 	    cdev->private->state != DEV_STATE_W4SENSE)
155 		return -EINVAL;
156 	sch = to_subchannel(cdev->dev.parent);
157 	if (!sch)
158 		return -ENODEV;
159 	ret = cio_halt(sch);
160 	if (ret == 0)
161 		cdev->private->intparm = intparm;
162 	return ret;
163 }
164 
165 int
166 ccw_device_resume(struct ccw_device *cdev)
167 {
168 	struct subchannel *sch;
169 
170 	if (!cdev)
171 		return -ENODEV;
172 	sch = to_subchannel(cdev->dev.parent);
173 	if (!sch)
174 		return -ENODEV;
175 	if (cdev->private->state == DEV_STATE_NOT_OPER)
176 		return -ENODEV;
177 	if (cdev->private->state != DEV_STATE_ONLINE ||
178 	    !(sch->schib.scsw.actl & SCSW_ACTL_SUSPENDED))
179 		return -EINVAL;
180 	return cio_resume(sch);
181 }
182 
183 /*
184  * Pass interrupt to device driver.
185  */
186 int
187 ccw_device_call_handler(struct ccw_device *cdev)
188 {
189 	struct subchannel *sch;
190 	unsigned int stctl;
191 	int ending_status;
192 
193 	sch = to_subchannel(cdev->dev.parent);
194 
195 	/*
196 	 * we allow for the device action handler if .
197 	 *  - we received ending status
198 	 *  - the action handler requested to see all interrupts
199 	 *  - we received an intermediate status
200 	 *  - fast notification was requested (primary status)
201 	 *  - unsolicited interrupts
202 	 */
203 	stctl = cdev->private->irb.scsw.stctl;
204 	ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
205 		(stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
206 		(stctl == SCSW_STCTL_STATUS_PEND);
207 	if (!ending_status &&
208 	    !cdev->private->options.repall &&
209 	    !(stctl & SCSW_STCTL_INTER_STATUS) &&
210 	    !(cdev->private->options.fast &&
211 	      (stctl & SCSW_STCTL_PRIM_STATUS)))
212 		return 0;
213 
214 	/*
215 	 * Now we are ready to call the device driver interrupt handler.
216 	 */
217 	if (cdev->handler)
218 		cdev->handler(cdev, cdev->private->intparm,
219 			      &cdev->private->irb);
220 
221 	/*
222 	 * Clear the old and now useless interrupt response block.
223 	 */
224 	memset(&cdev->private->irb, 0, sizeof(struct irb));
225 
226 	return 1;
227 }
228 
229 /*
230  * Search for CIW command in extended sense data.
231  */
232 struct ciw *
233 ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
234 {
235 	int ciw_cnt;
236 
237 	if (cdev->private->flags.esid == 0)
238 		return NULL;
239 	for (ciw_cnt = 0; ciw_cnt < MAX_CIWS; ciw_cnt++)
240 		if (cdev->private->senseid.ciw[ciw_cnt].ct == ct)
241 			return cdev->private->senseid.ciw + ciw_cnt;
242 	return NULL;
243 }
244 
245 __u8
246 ccw_device_get_path_mask(struct ccw_device *cdev)
247 {
248 	struct subchannel *sch;
249 
250 	sch = to_subchannel(cdev->dev.parent);
251 	if (!sch)
252 		return 0;
253 	else
254 		return sch->vpm;
255 }
256 
257 static void
258 ccw_device_wake_up(struct ccw_device *cdev, unsigned long ip, struct irb *irb)
259 {
260 	if (!ip)
261 		/* unsolicited interrupt */
262 		return;
263 
264 	/* Abuse intparm for error reporting. */
265 	if (IS_ERR(irb))
266 		cdev->private->intparm = -EIO;
267 	else if ((irb->scsw.dstat !=
268 		  (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
269 		 (irb->scsw.cstat != 0)) {
270 		/*
271 		 * We didn't get channel end / device end. Check if path
272 		 * verification has been started; we can retry after it has
273 		 * finished. We also retry unit checks except for command reject
274 		 * or intervention required. Also check for long busy
275 		 * conditions.
276 		 */
277 		 if (cdev->private->flags.doverify ||
278 			 cdev->private->state == DEV_STATE_VERIFY)
279 			 cdev->private->intparm = -EAGAIN;
280 		 if ((irb->scsw.dstat & DEV_STAT_UNIT_CHECK) &&
281 		     !(irb->ecw[0] &
282 		       (SNS0_CMD_REJECT | SNS0_INTERVENTION_REQ)))
283 			 cdev->private->intparm = -EAGAIN;
284 		else if ((irb->scsw.dstat & DEV_STAT_ATTENTION) &&
285 			 (irb->scsw.dstat & DEV_STAT_DEV_END) &&
286 			 (irb->scsw.dstat & DEV_STAT_UNIT_EXCEP))
287 			cdev->private->intparm = -EAGAIN;
288 		 else
289 			 cdev->private->intparm = -EIO;
290 
291 	} else
292 		cdev->private->intparm = 0;
293 	wake_up(&cdev->private->wait_q);
294 }
295 
296 static inline int
297 __ccw_device_retry_loop(struct ccw_device *cdev, struct ccw1 *ccw, long magic, __u8 lpm)
298 {
299 	int ret;
300 	struct subchannel *sch;
301 
302 	sch = to_subchannel(cdev->dev.parent);
303 	do {
304 		ret = cio_start (sch, ccw, lpm);
305 		if ((ret == -EBUSY) || (ret == -EACCES)) {
306 			/* Try again later. */
307 			spin_unlock_irq(&sch->lock);
308 			msleep(10);
309 			spin_lock_irq(&sch->lock);
310 			continue;
311 		}
312 		if (ret != 0)
313 			/* Non-retryable error. */
314 			break;
315 		/* Wait for end of request. */
316 		cdev->private->intparm = magic;
317 		spin_unlock_irq(&sch->lock);
318 		wait_event(cdev->private->wait_q,
319 			   (cdev->private->intparm == -EIO) ||
320 			   (cdev->private->intparm == -EAGAIN) ||
321 			   (cdev->private->intparm == 0));
322 		spin_lock_irq(&sch->lock);
323 		/* Check at least for channel end / device end */
324 		if (cdev->private->intparm == -EIO) {
325 			/* Non-retryable error. */
326 			ret = -EIO;
327 			break;
328 		}
329 		if (cdev->private->intparm == 0)
330 			/* Success. */
331 			break;
332 		/* Try again later. */
333 		spin_unlock_irq(&sch->lock);
334 		msleep(10);
335 		spin_lock_irq(&sch->lock);
336 	} while (1);
337 
338 	return ret;
339 }
340 
341 /**
342  * read_dev_chars() - read device characteristics
343  * @param cdev   target ccw device
344  * @param buffer pointer to buffer for rdc data
345  * @param length size of rdc data
346  * @returns 0 for success, negative error value on failure
347  *
348  * Context:
349  *   called for online device, lock not held
350  **/
351 int
352 read_dev_chars (struct ccw_device *cdev, void **buffer, int length)
353 {
354 	void (*handler)(struct ccw_device *, unsigned long, struct irb *);
355 	struct subchannel *sch;
356 	int ret;
357 	struct ccw1 *rdc_ccw;
358 
359 	if (!cdev)
360 		return -ENODEV;
361 	if (!buffer || !length)
362 		return -EINVAL;
363 	sch = to_subchannel(cdev->dev.parent);
364 
365 	CIO_TRACE_EVENT (4, "rddevch");
366 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
367 
368 	rdc_ccw = kzalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
369 	if (!rdc_ccw)
370 		return -ENOMEM;
371 	rdc_ccw->cmd_code = CCW_CMD_RDC;
372 	rdc_ccw->count = length;
373 	rdc_ccw->flags = CCW_FLAG_SLI;
374 	ret = set_normalized_cda (rdc_ccw, (*buffer));
375 	if (ret != 0) {
376 		kfree(rdc_ccw);
377 		return ret;
378 	}
379 
380 	spin_lock_irq(&sch->lock);
381 	/* Save interrupt handler. */
382 	handler = cdev->handler;
383 	/* Temporarily install own handler. */
384 	cdev->handler = ccw_device_wake_up;
385 	if (cdev->private->state != DEV_STATE_ONLINE)
386 		ret = -ENODEV;
387 	else if (((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
388 		  !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
389 		 cdev->private->flags.doverify)
390 		ret = -EBUSY;
391 	else
392 		/* 0x00D9C4C3 == ebcdic "RDC" */
393 		ret = __ccw_device_retry_loop(cdev, rdc_ccw, 0x00D9C4C3, 0);
394 
395 	/* Restore interrupt handler. */
396 	cdev->handler = handler;
397 	spin_unlock_irq(&sch->lock);
398 
399 	clear_normalized_cda (rdc_ccw);
400 	kfree(rdc_ccw);
401 
402 	return ret;
403 }
404 
405 /*
406  *  Read Configuration data using path mask
407  */
408 int
409 read_conf_data_lpm (struct ccw_device *cdev, void **buffer, int *length, __u8 lpm)
410 {
411 	void (*handler)(struct ccw_device *, unsigned long, struct irb *);
412 	struct subchannel *sch;
413 	struct ciw *ciw;
414 	char *rcd_buf;
415 	int ret;
416 	struct ccw1 *rcd_ccw;
417 
418 	if (!cdev)
419 		return -ENODEV;
420 	if (!buffer || !length)
421 		return -EINVAL;
422 	sch = to_subchannel(cdev->dev.parent);
423 
424 	CIO_TRACE_EVENT (4, "rdconf");
425 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
426 
427 	/*
428 	 * scan for RCD command in extended SenseID data
429 	 */
430 	ciw = ccw_device_get_ciw(cdev, CIW_TYPE_RCD);
431 	if (!ciw || ciw->cmd == 0)
432 		return -EOPNOTSUPP;
433 
434 	rcd_ccw = kzalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
435 	if (!rcd_ccw)
436 		return -ENOMEM;
437 	rcd_buf = kzalloc(ciw->count, GFP_KERNEL | GFP_DMA);
438  	if (!rcd_buf) {
439 		kfree(rcd_ccw);
440 		return -ENOMEM;
441 	}
442 	rcd_ccw->cmd_code = ciw->cmd;
443 	rcd_ccw->cda = (__u32) __pa (rcd_buf);
444 	rcd_ccw->count = ciw->count;
445 	rcd_ccw->flags = CCW_FLAG_SLI;
446 
447 	spin_lock_irq(&sch->lock);
448 	/* Save interrupt handler. */
449 	handler = cdev->handler;
450 	/* Temporarily install own handler. */
451 	cdev->handler = ccw_device_wake_up;
452 	if (cdev->private->state != DEV_STATE_ONLINE)
453 		ret = -ENODEV;
454 	else if (((sch->schib.scsw.stctl & SCSW_STCTL_PRIM_STATUS) &&
455 		  !(sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS)) ||
456 		 cdev->private->flags.doverify)
457 		ret = -EBUSY;
458 	else
459 		/* 0x00D9C3C4 == ebcdic "RCD" */
460 		ret = __ccw_device_retry_loop(cdev, rcd_ccw, 0x00D9C3C4, lpm);
461 
462 	/* Restore interrupt handler. */
463 	cdev->handler = handler;
464 	spin_unlock_irq(&sch->lock);
465 
466  	/*
467  	 * on success we update the user input parms
468  	 */
469  	if (ret) {
470  		kfree (rcd_buf);
471  		*buffer = NULL;
472  		*length = 0;
473  	} else {
474 		*length = ciw->count;
475 		*buffer = rcd_buf;
476 	}
477 	kfree(rcd_ccw);
478 
479 	return ret;
480 }
481 
482 /*
483  *  Read Configuration data
484  */
485 int
486 read_conf_data (struct ccw_device *cdev, void **buffer, int *length)
487 {
488 	return read_conf_data_lpm (cdev, buffer, length, 0);
489 }
490 
491 /*
492  * Try to break the lock on a boxed device.
493  */
494 int
495 ccw_device_stlck(struct ccw_device *cdev)
496 {
497 	void *buf, *buf2;
498 	unsigned long flags;
499 	struct subchannel *sch;
500 	int ret;
501 
502 	if (!cdev)
503 		return -ENODEV;
504 
505 	if (cdev->drv && !cdev->private->options.force)
506 		return -EINVAL;
507 
508 	sch = to_subchannel(cdev->dev.parent);
509 
510 	CIO_TRACE_EVENT(2, "stl lock");
511 	CIO_TRACE_EVENT(2, cdev->dev.bus_id);
512 
513 	buf = kmalloc(32*sizeof(char), GFP_DMA|GFP_KERNEL);
514 	if (!buf)
515 		return -ENOMEM;
516 	buf2 = kmalloc(32*sizeof(char), GFP_DMA|GFP_KERNEL);
517 	if (!buf2) {
518 		kfree(buf);
519 		return -ENOMEM;
520 	}
521 	spin_lock_irqsave(&sch->lock, flags);
522 	ret = cio_enable_subchannel(sch, 3);
523 	if (ret)
524 		goto out_unlock;
525 	/*
526 	 * Setup ccw. We chain an unconditional reserve and a release so we
527 	 * only break the lock.
528 	 */
529 	cdev->private->iccws[0].cmd_code = CCW_CMD_STLCK;
530 	cdev->private->iccws[0].cda = (__u32) __pa(buf);
531 	cdev->private->iccws[0].count = 32;
532 	cdev->private->iccws[0].flags = CCW_FLAG_CC;
533 	cdev->private->iccws[1].cmd_code = CCW_CMD_RELEASE;
534 	cdev->private->iccws[1].cda = (__u32) __pa(buf2);
535 	cdev->private->iccws[1].count = 32;
536 	cdev->private->iccws[1].flags = 0;
537 	ret = cio_start(sch, cdev->private->iccws, 0);
538 	if (ret) {
539 		cio_disable_subchannel(sch); //FIXME: return code?
540 		goto out_unlock;
541 	}
542 	cdev->private->irb.scsw.actl |= SCSW_ACTL_START_PEND;
543 	spin_unlock_irqrestore(&sch->lock, flags);
544 	wait_event(cdev->private->wait_q, cdev->private->irb.scsw.actl == 0);
545 	spin_lock_irqsave(&sch->lock, flags);
546 	cio_disable_subchannel(sch); //FIXME: return code?
547 	if ((cdev->private->irb.scsw.dstat !=
548 	     (DEV_STAT_CHN_END|DEV_STAT_DEV_END)) ||
549 	    (cdev->private->irb.scsw.cstat != 0))
550 		ret = -EIO;
551 	/* Clear irb. */
552 	memset(&cdev->private->irb, 0, sizeof(struct irb));
553 out_unlock:
554 	kfree(buf);
555 	kfree(buf2);
556 	spin_unlock_irqrestore(&sch->lock, flags);
557 	return ret;
558 }
559 
560 void *
561 ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no)
562 {
563 	struct subchannel *sch;
564 
565 	sch = to_subchannel(cdev->dev.parent);
566 	return chsc_get_chp_desc(sch, chp_no);
567 }
568 
569 // FIXME: these have to go:
570 
571 int
572 _ccw_device_get_subchannel_number(struct ccw_device *cdev)
573 {
574 	return cdev->private->sch_no;
575 }
576 
577 int
578 _ccw_device_get_device_number(struct ccw_device *cdev)
579 {
580 	return cdev->private->devno;
581 }
582 
583 
584 MODULE_LICENSE("GPL");
585 EXPORT_SYMBOL(ccw_device_set_options);
586 EXPORT_SYMBOL(ccw_device_clear);
587 EXPORT_SYMBOL(ccw_device_halt);
588 EXPORT_SYMBOL(ccw_device_resume);
589 EXPORT_SYMBOL(ccw_device_start_timeout);
590 EXPORT_SYMBOL(ccw_device_start);
591 EXPORT_SYMBOL(ccw_device_start_timeout_key);
592 EXPORT_SYMBOL(ccw_device_start_key);
593 EXPORT_SYMBOL(ccw_device_get_ciw);
594 EXPORT_SYMBOL(ccw_device_get_path_mask);
595 EXPORT_SYMBOL(read_conf_data);
596 EXPORT_SYMBOL(read_dev_chars);
597 EXPORT_SYMBOL(_ccw_device_get_subchannel_number);
598 EXPORT_SYMBOL(_ccw_device_get_device_number);
599 EXPORT_SYMBOL_GPL(ccw_device_get_chp_desc);
600 EXPORT_SYMBOL_GPL(read_conf_data_lpm);
601