xref: /openbmc/linux/drivers/s390/cio/qdio_main.c (revision 2010776f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Linux for s390 qdio support, buffer handling, qdio API and module support.
4  *
5  * Copyright IBM Corp. 2000, 2008
6  * Author(s): Utz Bacher <utz.bacher@de.ibm.com>
7  *	      Jan Glauber <jang@linux.vnet.ibm.com>
8  * 2.6 cio integration by Cornelia Huck <cornelia.huck@de.ibm.com>
9  */
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14 #include <linux/gfp.h>
15 #include <linux/io.h>
16 #include <linux/atomic.h>
17 #include <asm/debug.h>
18 #include <asm/qdio.h>
19 #include <asm/ipl.h>
20 
21 #include "cio.h"
22 #include "css.h"
23 #include "device.h"
24 #include "qdio.h"
25 #include "qdio_debug.h"
26 
27 MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>,"\
28 	"Jan Glauber <jang@linux.vnet.ibm.com>");
29 MODULE_DESCRIPTION("QDIO base support");
30 MODULE_LICENSE("GPL");
31 
32 static inline int do_siga_sync(unsigned long schid,
33 			       unsigned long out_mask, unsigned long in_mask,
34 			       unsigned int fc)
35 {
36 	int cc;
37 
38 	asm volatile(
39 		"	lgr	0,%[fc]\n"
40 		"	lgr	1,%[schid]\n"
41 		"	lgr	2,%[out]\n"
42 		"	lgr	3,%[in]\n"
43 		"	siga	0\n"
44 		"	ipm	%[cc]\n"
45 		"	srl	%[cc],28\n"
46 		: [cc] "=&d" (cc)
47 		: [fc] "d" (fc), [schid] "d" (schid),
48 		  [out] "d" (out_mask), [in] "d" (in_mask)
49 		: "cc", "0", "1", "2", "3");
50 	return cc;
51 }
52 
53 static inline int do_siga_input(unsigned long schid, unsigned long mask,
54 				unsigned long fc)
55 {
56 	int cc;
57 
58 	asm volatile(
59 		"	lgr	0,%[fc]\n"
60 		"	lgr	1,%[schid]\n"
61 		"	lgr	2,%[mask]\n"
62 		"	siga	0\n"
63 		"	ipm	%[cc]\n"
64 		"	srl	%[cc],28\n"
65 		: [cc] "=&d" (cc)
66 		: [fc] "d" (fc), [schid] "d" (schid), [mask] "d" (mask)
67 		: "cc", "0", "1", "2");
68 	return cc;
69 }
70 
71 /**
72  * do_siga_output - perform SIGA-w/wt function
73  * @schid: subchannel id or in case of QEBSM the subchannel token
74  * @mask: which output queues to process
75  * @bb: busy bit indicator, set only if SIGA-w/wt could not access a buffer
76  * @fc: function code to perform
77  * @aob: asynchronous operation block
78  *
79  * Returns condition code.
80  * Note: For IQDC unicast queues only the highest priority queue is processed.
81  */
82 static inline int do_siga_output(unsigned long schid, unsigned long mask,
83 				 unsigned int *bb, unsigned long fc,
84 				 unsigned long aob)
85 {
86 	int cc;
87 
88 	asm volatile(
89 		"	lgr	0,%[fc]\n"
90 		"	lgr	1,%[schid]\n"
91 		"	lgr	2,%[mask]\n"
92 		"	lgr	3,%[aob]\n"
93 		"	siga	0\n"
94 		"	lgr	%[fc],0\n"
95 		"	ipm	%[cc]\n"
96 		"	srl	%[cc],28\n"
97 		: [cc] "=&d" (cc), [fc] "+&d" (fc)
98 		: [schid] "d" (schid), [mask] "d" (mask), [aob] "d" (aob)
99 		: "cc", "0", "1", "2", "3");
100 	*bb = fc >> 31;
101 	return cc;
102 }
103 
104 /**
105  * qdio_do_eqbs - extract buffer states for QEBSM
106  * @q: queue to manipulate
107  * @state: state of the extracted buffers
108  * @start: buffer number to start at
109  * @count: count of buffers to examine
110  * @auto_ack: automatically acknowledge buffers
111  *
112  * Returns the number of successfully extracted equal buffer states.
113  * Stops processing if a state is different from the last buffers state.
114  */
115 static int qdio_do_eqbs(struct qdio_q *q, unsigned char *state,
116 			int start, int count, int auto_ack)
117 {
118 	int tmp_count = count, tmp_start = start, nr = q->nr;
119 	unsigned int ccq = 0;
120 
121 	qperf_inc(q, eqbs);
122 
123 	if (!q->is_input_q)
124 		nr += q->irq_ptr->nr_input_qs;
125 again:
126 	ccq = do_eqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count,
127 		      auto_ack);
128 
129 	switch (ccq) {
130 	case 0:
131 	case 32:
132 		/* all done, or next buffer state different */
133 		return count - tmp_count;
134 	case 96:
135 		/* not all buffers processed */
136 		qperf_inc(q, eqbs_partial);
137 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "EQBS part:%02x",
138 			tmp_count);
139 		return count - tmp_count;
140 	case 97:
141 		/* no buffer processed */
142 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "EQBS again:%2d", ccq);
143 		goto again;
144 	default:
145 		DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
146 		DBF_ERROR("%4x EQBS ERROR", SCH_NO(q));
147 		DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
148 		q->handler(q->irq_ptr->cdev, QDIO_ERROR_GET_BUF_STATE, q->nr,
149 			   q->first_to_check, count, q->irq_ptr->int_parm);
150 		return 0;
151 	}
152 }
153 
154 /**
155  * qdio_do_sqbs - set buffer states for QEBSM
156  * @q: queue to manipulate
157  * @state: new state of the buffers
158  * @start: first buffer number to change
159  * @count: how many buffers to change
160  *
161  * Returns the number of successfully changed buffers.
162  * Does retrying until the specified count of buffer states is set or an
163  * error occurs.
164  */
165 static int qdio_do_sqbs(struct qdio_q *q, unsigned char state, int start,
166 			int count)
167 {
168 	unsigned int ccq = 0;
169 	int tmp_count = count, tmp_start = start;
170 	int nr = q->nr;
171 
172 	if (!count)
173 		return 0;
174 	qperf_inc(q, sqbs);
175 
176 	if (!q->is_input_q)
177 		nr += q->irq_ptr->nr_input_qs;
178 again:
179 	ccq = do_sqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count);
180 
181 	switch (ccq) {
182 	case 0:
183 	case 32:
184 		/* all done, or active buffer adapter-owned */
185 		WARN_ON_ONCE(tmp_count);
186 		return count - tmp_count;
187 	case 96:
188 		/* not all buffers processed */
189 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "SQBS again:%2d", ccq);
190 		qperf_inc(q, sqbs_partial);
191 		goto again;
192 	default:
193 		DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
194 		DBF_ERROR("%4x SQBS ERROR", SCH_NO(q));
195 		DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
196 		q->handler(q->irq_ptr->cdev, QDIO_ERROR_SET_BUF_STATE, q->nr,
197 			   q->first_to_check, count, q->irq_ptr->int_parm);
198 		return 0;
199 	}
200 }
201 
202 /*
203  * Returns number of examined buffers and their common state in *state.
204  * Requested number of buffers-to-examine must be > 0.
205  */
206 static inline int get_buf_states(struct qdio_q *q, unsigned int bufnr,
207 				 unsigned char *state, unsigned int count,
208 				 int auto_ack)
209 {
210 	unsigned char __state = 0;
211 	int i = 1;
212 
213 	if (is_qebsm(q))
214 		return qdio_do_eqbs(q, state, bufnr, count, auto_ack);
215 
216 	/* get initial state: */
217 	__state = q->slsb.val[bufnr];
218 
219 	/* Bail out early if there is no work on the queue: */
220 	if (__state & SLSB_OWNER_CU)
221 		goto out;
222 
223 	for (; i < count; i++) {
224 		bufnr = next_buf(bufnr);
225 
226 		/* stop if next state differs from initial state: */
227 		if (q->slsb.val[bufnr] != __state)
228 			break;
229 	}
230 
231 out:
232 	*state = __state;
233 	return i;
234 }
235 
236 static inline int get_buf_state(struct qdio_q *q, unsigned int bufnr,
237 				unsigned char *state, int auto_ack)
238 {
239 	return get_buf_states(q, bufnr, state, 1, auto_ack);
240 }
241 
242 /* wrap-around safe setting of slsb states, returns number of changed buffers */
243 static inline int set_buf_states(struct qdio_q *q, int bufnr,
244 				 unsigned char state, int count)
245 {
246 	int i;
247 
248 	if (is_qebsm(q))
249 		return qdio_do_sqbs(q, state, bufnr, count);
250 
251 	/* Ensure that all preceding changes to the SBALs are visible: */
252 	mb();
253 
254 	for (i = 0; i < count; i++) {
255 		WRITE_ONCE(q->slsb.val[bufnr], state);
256 		bufnr = next_buf(bufnr);
257 	}
258 
259 	/* Make our SLSB changes visible: */
260 	mb();
261 
262 	return count;
263 }
264 
265 static inline int set_buf_state(struct qdio_q *q, int bufnr,
266 				unsigned char state)
267 {
268 	return set_buf_states(q, bufnr, state, 1);
269 }
270 
271 /* set slsb states to initial state */
272 static void qdio_init_buf_states(struct qdio_irq *irq_ptr)
273 {
274 	struct qdio_q *q;
275 	int i;
276 
277 	for_each_input_queue(irq_ptr, q, i)
278 		set_buf_states(q, 0, SLSB_P_INPUT_NOT_INIT,
279 			       QDIO_MAX_BUFFERS_PER_Q);
280 	for_each_output_queue(irq_ptr, q, i)
281 		set_buf_states(q, 0, SLSB_P_OUTPUT_NOT_INIT,
282 			       QDIO_MAX_BUFFERS_PER_Q);
283 }
284 
285 static inline int qdio_siga_sync(struct qdio_q *q, unsigned int output,
286 			  unsigned int input)
287 {
288 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
289 	unsigned int fc = QDIO_SIGA_SYNC;
290 	int cc;
291 
292 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-s:%1d", q->nr);
293 	qperf_inc(q, siga_sync);
294 
295 	if (is_qebsm(q)) {
296 		schid = q->irq_ptr->sch_token;
297 		fc |= QDIO_SIGA_QEBSM_FLAG;
298 	}
299 
300 	cc = do_siga_sync(schid, output, input, fc);
301 	if (unlikely(cc))
302 		DBF_ERROR("%4x SIGA-S:%2d", SCH_NO(q), cc);
303 	return (cc) ? -EIO : 0;
304 }
305 
306 static inline int qdio_sync_input_queue(struct qdio_q *q)
307 {
308 	return qdio_siga_sync(q, 0, q->mask);
309 }
310 
311 static inline int qdio_sync_output_queue(struct qdio_q *q)
312 {
313 	return qdio_siga_sync(q, q->mask, 0);
314 }
315 
316 static inline int qdio_siga_sync_q(struct qdio_q *q)
317 {
318 	if (q->is_input_q)
319 		return qdio_sync_input_queue(q);
320 	else
321 		return qdio_sync_output_queue(q);
322 }
323 
324 static int qdio_siga_output(struct qdio_q *q, unsigned int count,
325 			    unsigned int *busy_bit, unsigned long aob)
326 {
327 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
328 	unsigned int fc = QDIO_SIGA_WRITE;
329 	u64 start_time = 0;
330 	int retries = 0, cc;
331 
332 	if (queue_type(q) == QDIO_IQDIO_QFMT && !multicast_outbound(q)) {
333 		if (count > 1)
334 			fc = QDIO_SIGA_WRITEM;
335 		else if (aob)
336 			fc = QDIO_SIGA_WRITEQ;
337 	}
338 
339 	if (is_qebsm(q)) {
340 		schid = q->irq_ptr->sch_token;
341 		fc |= QDIO_SIGA_QEBSM_FLAG;
342 	}
343 again:
344 	cc = do_siga_output(schid, q->mask, busy_bit, fc, aob);
345 
346 	/* hipersocket busy condition */
347 	if (unlikely(*busy_bit)) {
348 		retries++;
349 
350 		if (!start_time) {
351 			start_time = get_tod_clock_fast();
352 			goto again;
353 		}
354 		if (get_tod_clock_fast() - start_time < QDIO_BUSY_BIT_PATIENCE)
355 			goto again;
356 	}
357 	if (retries) {
358 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr,
359 			      "%4x cc2 BB1:%1d", SCH_NO(q), q->nr);
360 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "count:%u", retries);
361 	}
362 	return cc;
363 }
364 
365 static inline int qdio_siga_input(struct qdio_q *q)
366 {
367 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
368 	unsigned int fc = QDIO_SIGA_READ;
369 	int cc;
370 
371 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-r:%1d", q->nr);
372 	qperf_inc(q, siga_read);
373 
374 	if (is_qebsm(q)) {
375 		schid = q->irq_ptr->sch_token;
376 		fc |= QDIO_SIGA_QEBSM_FLAG;
377 	}
378 
379 	cc = do_siga_input(schid, q->mask, fc);
380 	if (unlikely(cc))
381 		DBF_ERROR("%4x SIGA-R:%2d", SCH_NO(q), cc);
382 	return (cc) ? -EIO : 0;
383 }
384 
385 int debug_get_buf_state(struct qdio_q *q, unsigned int bufnr,
386 			unsigned char *state)
387 {
388 	if (qdio_need_siga_sync(q->irq_ptr))
389 		qdio_siga_sync_q(q);
390 	return get_buf_state(q, bufnr, state, 0);
391 }
392 
393 static inline void qdio_stop_polling(struct qdio_q *q)
394 {
395 	if (!q->u.in.batch_count)
396 		return;
397 
398 	qperf_inc(q, stop_polling);
399 
400 	/* show the card that we are not polling anymore */
401 	set_buf_states(q, q->u.in.batch_start, SLSB_P_INPUT_NOT_INIT,
402 		       q->u.in.batch_count);
403 	q->u.in.batch_count = 0;
404 }
405 
406 static inline void account_sbals(struct qdio_q *q, unsigned int count)
407 {
408 	q->q_stats.nr_sbal_total += count;
409 	q->q_stats.nr_sbals[ilog2(count)]++;
410 }
411 
412 static void process_buffer_error(struct qdio_q *q, unsigned int start,
413 				 int count)
414 {
415 	/* special handling for no target buffer empty */
416 	if (queue_type(q) == QDIO_IQDIO_QFMT && !q->is_input_q &&
417 	    q->sbal[start]->element[15].sflags == 0x10) {
418 		qperf_inc(q, target_full);
419 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "OUTFULL FTC:%02x", start);
420 		return;
421 	}
422 
423 	DBF_ERROR("%4x BUF ERROR", SCH_NO(q));
424 	DBF_ERROR((q->is_input_q) ? "IN:%2d" : "OUT:%2d", q->nr);
425 	DBF_ERROR("FTC:%3d C:%3d", start, count);
426 	DBF_ERROR("F14:%2x F15:%2x",
427 		  q->sbal[start]->element[14].sflags,
428 		  q->sbal[start]->element[15].sflags);
429 }
430 
431 static inline void inbound_handle_work(struct qdio_q *q, unsigned int start,
432 				       int count, bool auto_ack)
433 {
434 	/* ACK the newest SBAL: */
435 	if (!auto_ack)
436 		set_buf_state(q, add_buf(start, count - 1), SLSB_P_INPUT_ACK);
437 
438 	if (!q->u.in.batch_count)
439 		q->u.in.batch_start = start;
440 	q->u.in.batch_count += count;
441 }
442 
443 static int get_inbound_buffer_frontier(struct qdio_q *q, unsigned int start,
444 				       unsigned int *error)
445 {
446 	unsigned char state = 0;
447 	int count;
448 
449 	q->timestamp = get_tod_clock_fast();
450 
451 	count = atomic_read(&q->nr_buf_used);
452 	if (!count)
453 		return 0;
454 
455 	if (qdio_need_siga_sync(q->irq_ptr))
456 		qdio_sync_input_queue(q);
457 
458 	count = get_buf_states(q, start, &state, count, 1);
459 	if (!count)
460 		return 0;
461 
462 	switch (state) {
463 	case SLSB_P_INPUT_PRIMED:
464 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in prim:%1d %02x", q->nr,
465 			      count);
466 
467 		inbound_handle_work(q, start, count, is_qebsm(q));
468 		if (atomic_sub_return(count, &q->nr_buf_used) == 0)
469 			qperf_inc(q, inbound_queue_full);
470 		if (q->irq_ptr->perf_stat_enabled)
471 			account_sbals(q, count);
472 		return count;
473 	case SLSB_P_INPUT_ERROR:
474 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in err:%1d %02x", q->nr,
475 			      count);
476 
477 		*error = QDIO_ERROR_SLSB_STATE;
478 		process_buffer_error(q, start, count);
479 		inbound_handle_work(q, start, count, false);
480 		if (atomic_sub_return(count, &q->nr_buf_used) == 0)
481 			qperf_inc(q, inbound_queue_full);
482 		if (q->irq_ptr->perf_stat_enabled)
483 			account_sbals_error(q, count);
484 		return count;
485 	case SLSB_CU_INPUT_EMPTY:
486 		if (q->irq_ptr->perf_stat_enabled)
487 			q->q_stats.nr_sbal_nop++;
488 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in nop:%1d %#02x",
489 			      q->nr, start);
490 		return 0;
491 	case SLSB_P_INPUT_NOT_INIT:
492 	case SLSB_P_INPUT_ACK:
493 		/* We should never see this state, throw a WARN: */
494 	default:
495 		dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
496 			      "found state %#x at index %u on queue %u\n",
497 			      state, start, q->nr);
498 		return 0;
499 	}
500 }
501 
502 static inline int qdio_inbound_q_done(struct qdio_q *q, unsigned int start)
503 {
504 	unsigned char state = 0;
505 
506 	if (!atomic_read(&q->nr_buf_used))
507 		return 1;
508 
509 	if (qdio_need_siga_sync(q->irq_ptr))
510 		qdio_sync_input_queue(q);
511 	get_buf_state(q, start, &state, 0);
512 
513 	if (state == SLSB_P_INPUT_PRIMED || state == SLSB_P_INPUT_ERROR)
514 		/* more work coming */
515 		return 0;
516 
517 	return 1;
518 }
519 
520 static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start,
521 					unsigned int *error)
522 {
523 	unsigned char state = 0;
524 	int count;
525 
526 	q->timestamp = get_tod_clock_fast();
527 
528 	count = atomic_read(&q->nr_buf_used);
529 	if (!count)
530 		return 0;
531 
532 	if (qdio_need_siga_sync(q->irq_ptr))
533 		qdio_sync_output_queue(q);
534 
535 	count = get_buf_states(q, start, &state, count, 0);
536 	if (!count)
537 		return 0;
538 
539 	switch (state) {
540 	case SLSB_P_OUTPUT_PENDING:
541 		*error = QDIO_ERROR_SLSB_PENDING;
542 		fallthrough;
543 	case SLSB_P_OUTPUT_EMPTY:
544 		/* the adapter got it */
545 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
546 			"out empty:%1d %02x", q->nr, count);
547 
548 		atomic_sub(count, &q->nr_buf_used);
549 		if (q->irq_ptr->perf_stat_enabled)
550 			account_sbals(q, count);
551 		return count;
552 	case SLSB_P_OUTPUT_ERROR:
553 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out error:%1d %02x",
554 			      q->nr, count);
555 
556 		*error = QDIO_ERROR_SLSB_STATE;
557 		process_buffer_error(q, start, count);
558 		atomic_sub(count, &q->nr_buf_used);
559 		if (q->irq_ptr->perf_stat_enabled)
560 			account_sbals_error(q, count);
561 		return count;
562 	case SLSB_CU_OUTPUT_PRIMED:
563 		/* the adapter has not fetched the output yet */
564 		if (q->irq_ptr->perf_stat_enabled)
565 			q->q_stats.nr_sbal_nop++;
566 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out primed:%1d",
567 			      q->nr);
568 		return 0;
569 	case SLSB_P_OUTPUT_HALTED:
570 		return 0;
571 	case SLSB_P_OUTPUT_NOT_INIT:
572 		/* We should never see this state, throw a WARN: */
573 	default:
574 		dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
575 			      "found state %#x at index %u on queue %u\n",
576 			      state, start, q->nr);
577 		return 0;
578 	}
579 }
580 
581 static int qdio_kick_outbound_q(struct qdio_q *q, unsigned int count,
582 				unsigned long aob)
583 {
584 	int retries = 0, cc;
585 	unsigned int busy_bit;
586 
587 	if (!qdio_need_siga_out(q->irq_ptr))
588 		return 0;
589 
590 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w:%1d", q->nr);
591 retry:
592 	qperf_inc(q, siga_write);
593 
594 	cc = qdio_siga_output(q, count, &busy_bit, aob);
595 	switch (cc) {
596 	case 0:
597 		break;
598 	case 2:
599 		if (busy_bit) {
600 			while (++retries < QDIO_BUSY_BIT_RETRIES) {
601 				mdelay(QDIO_BUSY_BIT_RETRY_DELAY);
602 				goto retry;
603 			}
604 			DBF_ERROR("%4x cc2 BBC:%1d", SCH_NO(q), q->nr);
605 			cc = -EBUSY;
606 		} else {
607 			DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w cc2:%1d", q->nr);
608 			cc = -ENOBUFS;
609 		}
610 		break;
611 	case 1:
612 	case 3:
613 		DBF_ERROR("%4x SIGA-W:%1d", SCH_NO(q), cc);
614 		cc = -EIO;
615 		break;
616 	}
617 	if (retries) {
618 		DBF_ERROR("%4x cc2 BB2:%1d", SCH_NO(q), q->nr);
619 		DBF_ERROR("count:%u", retries);
620 	}
621 	return cc;
622 }
623 
624 static inline void qdio_set_state(struct qdio_irq *irq_ptr,
625 				  enum qdio_irq_states state)
626 {
627 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "newstate: %1d", state);
628 
629 	irq_ptr->state = state;
630 	mb();
631 }
632 
633 static void qdio_irq_check_sense(struct qdio_irq *irq_ptr, struct irb *irb)
634 {
635 	if (irb->esw.esw0.erw.cons) {
636 		DBF_ERROR("%4x sense:", irq_ptr->schid.sch_no);
637 		DBF_ERROR_HEX(irb, 64);
638 		DBF_ERROR_HEX(irb->ecw, 64);
639 	}
640 }
641 
642 /* PCI interrupt handler */
643 static void qdio_int_handler_pci(struct qdio_irq *irq_ptr)
644 {
645 	if (unlikely(irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
646 		return;
647 
648 	qdio_deliver_irq(irq_ptr);
649 	irq_ptr->last_data_irq_time = S390_lowcore.int_clock;
650 }
651 
652 static void qdio_handle_activate_check(struct qdio_irq *irq_ptr,
653 				       unsigned long intparm, int cstat,
654 				       int dstat)
655 {
656 	struct qdio_q *q;
657 
658 	DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
659 	DBF_ERROR("intp :%lx", intparm);
660 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
661 
662 	if (irq_ptr->nr_input_qs) {
663 		q = irq_ptr->input_qs[0];
664 	} else if (irq_ptr->nr_output_qs) {
665 		q = irq_ptr->output_qs[0];
666 	} else {
667 		dump_stack();
668 		goto no_handler;
669 	}
670 
671 	q->handler(q->irq_ptr->cdev, QDIO_ERROR_ACTIVATE,
672 		   q->nr, q->first_to_check, 0, irq_ptr->int_parm);
673 no_handler:
674 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
675 	/*
676 	 * In case of z/VM LGR (Live Guest Migration) QDIO recovery will happen.
677 	 * Therefore we call the LGR detection function here.
678 	 */
679 	lgr_info_log();
680 }
681 
682 static void qdio_establish_handle_irq(struct qdio_irq *irq_ptr, int cstat,
683 				      int dstat)
684 {
685 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qest irq");
686 
687 	if (cstat)
688 		goto error;
689 	if (dstat & ~(DEV_STAT_DEV_END | DEV_STAT_CHN_END))
690 		goto error;
691 	if (!(dstat & DEV_STAT_DEV_END))
692 		goto error;
693 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ESTABLISHED);
694 	return;
695 
696 error:
697 	DBF_ERROR("%4x EQ:error", irq_ptr->schid.sch_no);
698 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
699 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
700 }
701 
702 /* qdio interrupt handler */
703 void qdio_int_handler(struct ccw_device *cdev, unsigned long intparm,
704 		      struct irb *irb)
705 {
706 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
707 	struct subchannel_id schid;
708 	int cstat, dstat;
709 
710 	if (!intparm || !irq_ptr) {
711 		ccw_device_get_schid(cdev, &schid);
712 		DBF_ERROR("qint:%4x", schid.sch_no);
713 		return;
714 	}
715 
716 	if (irq_ptr->perf_stat_enabled)
717 		irq_ptr->perf_stat.qdio_int++;
718 
719 	if (IS_ERR(irb)) {
720 		DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
721 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
722 		wake_up(&cdev->private->wait_q);
723 		return;
724 	}
725 	qdio_irq_check_sense(irq_ptr, irb);
726 	cstat = irb->scsw.cmd.cstat;
727 	dstat = irb->scsw.cmd.dstat;
728 
729 	switch (irq_ptr->state) {
730 	case QDIO_IRQ_STATE_INACTIVE:
731 		qdio_establish_handle_irq(irq_ptr, cstat, dstat);
732 		break;
733 	case QDIO_IRQ_STATE_CLEANUP:
734 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
735 		break;
736 	case QDIO_IRQ_STATE_ESTABLISHED:
737 	case QDIO_IRQ_STATE_ACTIVE:
738 		if (cstat & SCHN_STAT_PCI) {
739 			qdio_int_handler_pci(irq_ptr);
740 			return;
741 		}
742 		if (cstat || dstat)
743 			qdio_handle_activate_check(irq_ptr, intparm, cstat,
744 						   dstat);
745 		break;
746 	case QDIO_IRQ_STATE_STOPPED:
747 		break;
748 	default:
749 		WARN_ON_ONCE(1);
750 	}
751 	wake_up(&cdev->private->wait_q);
752 }
753 
754 /**
755  * qdio_get_ssqd_desc - get qdio subchannel description
756  * @cdev: ccw device to get description for
757  * @data: where to store the ssqd
758  *
759  * Returns 0 or an error code. The results of the chsc are stored in the
760  * specified structure.
761  */
762 int qdio_get_ssqd_desc(struct ccw_device *cdev,
763 		       struct qdio_ssqd_desc *data)
764 {
765 	struct subchannel_id schid;
766 
767 	if (!cdev || !cdev->private)
768 		return -EINVAL;
769 
770 	ccw_device_get_schid(cdev, &schid);
771 	DBF_EVENT("get ssqd:%4x", schid.sch_no);
772 	return qdio_setup_get_ssqd(NULL, &schid, data);
773 }
774 EXPORT_SYMBOL_GPL(qdio_get_ssqd_desc);
775 
776 static int qdio_cancel_ccw(struct qdio_irq *irq, int how)
777 {
778 	struct ccw_device *cdev = irq->cdev;
779 	long timeout;
780 	int rc;
781 
782 	spin_lock_irq(get_ccwdev_lock(cdev));
783 	qdio_set_state(irq, QDIO_IRQ_STATE_CLEANUP);
784 	if (how & QDIO_FLAG_CLEANUP_USING_CLEAR)
785 		rc = ccw_device_clear(cdev, QDIO_DOING_CLEANUP);
786 	else
787 		/* default behaviour is halt */
788 		rc = ccw_device_halt(cdev, QDIO_DOING_CLEANUP);
789 	spin_unlock_irq(get_ccwdev_lock(cdev));
790 	if (rc) {
791 		DBF_ERROR("%4x SHUTD ERR", irq->schid.sch_no);
792 		DBF_ERROR("rc:%4d", rc);
793 		return rc;
794 	}
795 
796 	timeout = wait_event_interruptible_timeout(cdev->private->wait_q,
797 						   irq->state == QDIO_IRQ_STATE_INACTIVE ||
798 						   irq->state == QDIO_IRQ_STATE_ERR,
799 						   10 * HZ);
800 	if (timeout <= 0)
801 		rc = (timeout == -ERESTARTSYS) ? -EINTR : -ETIME;
802 
803 	return rc;
804 }
805 
806 /**
807  * qdio_shutdown - shut down a qdio subchannel
808  * @cdev: associated ccw device
809  * @how: use halt or clear to shutdown
810  */
811 int qdio_shutdown(struct ccw_device *cdev, int how)
812 {
813 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
814 	struct subchannel_id schid;
815 	int rc;
816 
817 	if (!irq_ptr)
818 		return -ENODEV;
819 
820 	WARN_ON_ONCE(irqs_disabled());
821 	ccw_device_get_schid(cdev, &schid);
822 	DBF_EVENT("qshutdown:%4x", schid.sch_no);
823 
824 	mutex_lock(&irq_ptr->setup_mutex);
825 	/*
826 	 * Subchannel was already shot down. We cannot prevent being called
827 	 * twice since cio may trigger a shutdown asynchronously.
828 	 */
829 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
830 		mutex_unlock(&irq_ptr->setup_mutex);
831 		return 0;
832 	}
833 
834 	/*
835 	 * Indicate that the device is going down.
836 	 */
837 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
838 
839 	qdio_shutdown_debug_entries(irq_ptr);
840 
841 	rc = qdio_cancel_ccw(irq_ptr, how);
842 	qdio_shutdown_thinint(irq_ptr);
843 	qdio_shutdown_irq(irq_ptr);
844 
845 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
846 	mutex_unlock(&irq_ptr->setup_mutex);
847 	if (rc)
848 		return rc;
849 	return 0;
850 }
851 EXPORT_SYMBOL_GPL(qdio_shutdown);
852 
853 /**
854  * qdio_free - free data structures for a qdio subchannel
855  * @cdev: associated ccw device
856  */
857 int qdio_free(struct ccw_device *cdev)
858 {
859 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
860 	struct subchannel_id schid;
861 
862 	if (!irq_ptr)
863 		return -ENODEV;
864 
865 	ccw_device_get_schid(cdev, &schid);
866 	DBF_EVENT("qfree:%4x", schid.sch_no);
867 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf abandoned");
868 	mutex_lock(&irq_ptr->setup_mutex);
869 
870 	irq_ptr->debug_area = NULL;
871 	cdev->private->qdio_data = NULL;
872 	mutex_unlock(&irq_ptr->setup_mutex);
873 
874 	qdio_free_queues(irq_ptr);
875 	free_page((unsigned long) irq_ptr->qdr);
876 	free_page(irq_ptr->chsc_page);
877 	free_page((unsigned long) irq_ptr);
878 	return 0;
879 }
880 EXPORT_SYMBOL_GPL(qdio_free);
881 
882 /**
883  * qdio_allocate - allocate qdio queues and associated data
884  * @cdev: associated ccw device
885  * @no_input_qs: allocate this number of Input Queues
886  * @no_output_qs: allocate this number of Output Queues
887  */
888 int qdio_allocate(struct ccw_device *cdev, unsigned int no_input_qs,
889 		  unsigned int no_output_qs)
890 {
891 	struct subchannel_id schid;
892 	struct qdio_irq *irq_ptr;
893 	int rc = -ENOMEM;
894 
895 	ccw_device_get_schid(cdev, &schid);
896 	DBF_EVENT("qallocate:%4x", schid.sch_no);
897 
898 	if (no_input_qs > QDIO_MAX_QUEUES_PER_IRQ ||
899 	    no_output_qs > QDIO_MAX_QUEUES_PER_IRQ)
900 		return -EINVAL;
901 
902 	/* irq_ptr must be in GFP_DMA since it contains ccw1.cda */
903 	irq_ptr = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
904 	if (!irq_ptr)
905 		return -ENOMEM;
906 
907 	irq_ptr->cdev = cdev;
908 	mutex_init(&irq_ptr->setup_mutex);
909 	if (qdio_allocate_dbf(irq_ptr))
910 		goto err_dbf;
911 
912 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "alloc niq:%1u noq:%1u", no_input_qs,
913 		      no_output_qs);
914 
915 	/*
916 	 * Allocate a page for the chsc calls in qdio_establish.
917 	 * Must be pre-allocated since a zfcp recovery will call
918 	 * qdio_establish. In case of low memory and swap on a zfcp disk
919 	 * we may not be able to allocate memory otherwise.
920 	 */
921 	irq_ptr->chsc_page = get_zeroed_page(GFP_KERNEL);
922 	if (!irq_ptr->chsc_page)
923 		goto err_chsc;
924 
925 	/* qdr is used in ccw1.cda which is u32 */
926 	irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
927 	if (!irq_ptr->qdr)
928 		goto err_qdr;
929 
930 	rc = qdio_allocate_qs(irq_ptr, no_input_qs, no_output_qs);
931 	if (rc)
932 		goto err_queues;
933 
934 	cdev->private->qdio_data = irq_ptr;
935 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
936 	return 0;
937 
938 err_queues:
939 	free_page((unsigned long) irq_ptr->qdr);
940 err_qdr:
941 	free_page(irq_ptr->chsc_page);
942 err_chsc:
943 err_dbf:
944 	free_page((unsigned long) irq_ptr);
945 	return rc;
946 }
947 EXPORT_SYMBOL_GPL(qdio_allocate);
948 
949 static void qdio_trace_init_data(struct qdio_irq *irq,
950 				 struct qdio_initialize *data)
951 {
952 	DBF_DEV_EVENT(DBF_ERR, irq, "qfmt:%1u", data->q_format);
953 	DBF_DEV_EVENT(DBF_ERR, irq, "qpff%4x", data->qib_param_field_format);
954 	DBF_DEV_HEX(irq, &data->qib_param_field, sizeof(void *), DBF_ERR);
955 	DBF_DEV_EVENT(DBF_ERR, irq, "niq:%1u noq:%1u", data->no_input_qs,
956 		      data->no_output_qs);
957 	DBF_DEV_HEX(irq, &data->input_handler, sizeof(void *), DBF_ERR);
958 	DBF_DEV_HEX(irq, &data->output_handler, sizeof(void *), DBF_ERR);
959 	DBF_DEV_HEX(irq, &data->int_parm, sizeof(long), DBF_ERR);
960 	DBF_DEV_HEX(irq, &data->input_sbal_addr_array, sizeof(void *), DBF_ERR);
961 	DBF_DEV_HEX(irq, &data->output_sbal_addr_array, sizeof(void *),
962 		    DBF_ERR);
963 }
964 
965 /**
966  * qdio_establish - establish queues on a qdio subchannel
967  * @cdev: associated ccw device
968  * @init_data: initialization data
969  */
970 int qdio_establish(struct ccw_device *cdev,
971 		   struct qdio_initialize *init_data)
972 {
973 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
974 	struct subchannel_id schid;
975 	long timeout;
976 	int rc;
977 
978 	ccw_device_get_schid(cdev, &schid);
979 	DBF_EVENT("qestablish:%4x", schid.sch_no);
980 
981 	if (!irq_ptr)
982 		return -ENODEV;
983 
984 	if (init_data->no_input_qs > irq_ptr->max_input_qs ||
985 	    init_data->no_output_qs > irq_ptr->max_output_qs)
986 		return -EINVAL;
987 
988 	if ((init_data->no_input_qs && !init_data->input_handler) ||
989 	    (init_data->no_output_qs && !init_data->output_handler))
990 		return -EINVAL;
991 
992 	if (!init_data->input_sbal_addr_array ||
993 	    !init_data->output_sbal_addr_array)
994 		return -EINVAL;
995 
996 	if (!init_data->irq_poll)
997 		return -EINVAL;
998 
999 	mutex_lock(&irq_ptr->setup_mutex);
1000 	qdio_trace_init_data(irq_ptr, init_data);
1001 	qdio_setup_irq(irq_ptr, init_data);
1002 
1003 	rc = qdio_establish_thinint(irq_ptr);
1004 	if (rc)
1005 		goto err_thinint;
1006 
1007 	/* establish q */
1008 	irq_ptr->ccw.cmd_code = irq_ptr->equeue.cmd;
1009 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1010 	irq_ptr->ccw.count = irq_ptr->equeue.count;
1011 	irq_ptr->ccw.cda = (u32) virt_to_phys(irq_ptr->qdr);
1012 
1013 	spin_lock_irq(get_ccwdev_lock(cdev));
1014 	ccw_device_set_options_mask(cdev, 0);
1015 
1016 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ESTABLISH, 0, 0);
1017 	spin_unlock_irq(get_ccwdev_lock(cdev));
1018 	if (rc) {
1019 		DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no);
1020 		DBF_ERROR("rc:%4x", rc);
1021 		goto err_ccw_start;
1022 	}
1023 
1024 	timeout = wait_event_interruptible_timeout(cdev->private->wait_q,
1025 						   irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
1026 						   irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ);
1027 	if (timeout <= 0) {
1028 		rc = (timeout == -ERESTARTSYS) ? -EINTR : -ETIME;
1029 		goto err_ccw_timeout;
1030 	}
1031 
1032 	if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) {
1033 		rc = -EIO;
1034 		goto err_ccw_error;
1035 	}
1036 
1037 	qdio_setup_ssqd_info(irq_ptr);
1038 
1039 	/* qebsm is now setup if available, initialize buffer states */
1040 	qdio_init_buf_states(irq_ptr);
1041 
1042 	mutex_unlock(&irq_ptr->setup_mutex);
1043 	qdio_print_subchannel_info(irq_ptr);
1044 	qdio_setup_debug_entries(irq_ptr);
1045 	return 0;
1046 
1047 err_ccw_timeout:
1048 	qdio_cancel_ccw(irq_ptr, QDIO_FLAG_CLEANUP_USING_CLEAR);
1049 err_ccw_error:
1050 err_ccw_start:
1051 	qdio_shutdown_thinint(irq_ptr);
1052 err_thinint:
1053 	qdio_shutdown_irq(irq_ptr);
1054 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1055 	mutex_unlock(&irq_ptr->setup_mutex);
1056 	return rc;
1057 }
1058 EXPORT_SYMBOL_GPL(qdio_establish);
1059 
1060 /**
1061  * qdio_activate - activate queues on a qdio subchannel
1062  * @cdev: associated cdev
1063  */
1064 int qdio_activate(struct ccw_device *cdev)
1065 {
1066 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1067 	struct subchannel_id schid;
1068 	int rc;
1069 
1070 	ccw_device_get_schid(cdev, &schid);
1071 	DBF_EVENT("qactivate:%4x", schid.sch_no);
1072 
1073 	if (!irq_ptr)
1074 		return -ENODEV;
1075 
1076 	mutex_lock(&irq_ptr->setup_mutex);
1077 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1078 		rc = -EBUSY;
1079 		goto out;
1080 	}
1081 
1082 	irq_ptr->ccw.cmd_code = irq_ptr->aqueue.cmd;
1083 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1084 	irq_ptr->ccw.count = irq_ptr->aqueue.count;
1085 	irq_ptr->ccw.cda = 0;
1086 
1087 	spin_lock_irq(get_ccwdev_lock(cdev));
1088 	ccw_device_set_options(cdev, CCWDEV_REPORT_ALL);
1089 
1090 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ACTIVATE,
1091 			      0, DOIO_DENY_PREFETCH);
1092 	spin_unlock_irq(get_ccwdev_lock(cdev));
1093 	if (rc) {
1094 		DBF_ERROR("%4x act IO ERR", irq_ptr->schid.sch_no);
1095 		DBF_ERROR("rc:%4x", rc);
1096 		goto out;
1097 	}
1098 
1099 	/* wait for subchannel to become active */
1100 	msleep(5);
1101 
1102 	switch (irq_ptr->state) {
1103 	case QDIO_IRQ_STATE_STOPPED:
1104 	case QDIO_IRQ_STATE_ERR:
1105 		rc = -EIO;
1106 		break;
1107 	default:
1108 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ACTIVE);
1109 		rc = 0;
1110 	}
1111 out:
1112 	mutex_unlock(&irq_ptr->setup_mutex);
1113 	return rc;
1114 }
1115 EXPORT_SYMBOL_GPL(qdio_activate);
1116 
1117 /**
1118  * handle_inbound - reset processed input buffers
1119  * @q: queue containing the buffers
1120  * @bufnr: first buffer to process
1121  * @count: how many buffers are emptied
1122  */
1123 static int handle_inbound(struct qdio_q *q, int bufnr, int count)
1124 {
1125 	int overlap;
1126 
1127 	qperf_inc(q, inbound_call);
1128 
1129 	/* If any processed SBALs are returned to HW, adjust our tracking: */
1130 	overlap = min_t(int, count - sub_buf(q->u.in.batch_start, bufnr),
1131 			     q->u.in.batch_count);
1132 	if (overlap > 0) {
1133 		q->u.in.batch_start = add_buf(q->u.in.batch_start, overlap);
1134 		q->u.in.batch_count -= overlap;
1135 	}
1136 
1137 	count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
1138 	atomic_add(count, &q->nr_buf_used);
1139 
1140 	if (qdio_need_siga_in(q->irq_ptr))
1141 		return qdio_siga_input(q);
1142 
1143 	return 0;
1144 }
1145 
1146 /**
1147  * handle_outbound - process filled outbound buffers
1148  * @q: queue containing the buffers
1149  * @bufnr: first buffer to process
1150  * @count: how many buffers are filled
1151  * @aob: asynchronous operation block
1152  */
1153 static int handle_outbound(struct qdio_q *q, unsigned int bufnr, unsigned int count,
1154 			   struct qaob *aob)
1155 {
1156 	unsigned char state = 0;
1157 	int used, rc = 0;
1158 
1159 	qperf_inc(q, outbound_call);
1160 
1161 	count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
1162 	used = atomic_add_return(count, &q->nr_buf_used);
1163 
1164 	if (used == QDIO_MAX_BUFFERS_PER_Q)
1165 		qperf_inc(q, outbound_queue_full);
1166 
1167 	if (queue_type(q) == QDIO_IQDIO_QFMT) {
1168 		unsigned long phys_aob = aob ? virt_to_phys(aob) : 0;
1169 
1170 		WARN_ON_ONCE(!IS_ALIGNED(phys_aob, 256));
1171 		rc = qdio_kick_outbound_q(q, count, phys_aob);
1172 	} else if (qdio_need_siga_sync(q->irq_ptr)) {
1173 		rc = qdio_sync_output_queue(q);
1174 	} else if (count < QDIO_MAX_BUFFERS_PER_Q &&
1175 		   get_buf_state(q, prev_buf(bufnr), &state, 0) > 0 &&
1176 		   state == SLSB_CU_OUTPUT_PRIMED) {
1177 		/* The previous buffer is not processed yet, tack on. */
1178 		qperf_inc(q, fast_requeue);
1179 	} else {
1180 		rc = qdio_kick_outbound_q(q, count, 0);
1181 	}
1182 
1183 	return rc;
1184 }
1185 
1186 /**
1187  * do_QDIO - process input or output buffers
1188  * @cdev: associated ccw_device for the qdio subchannel
1189  * @callflags: input or output and special flags from the program
1190  * @q_nr: queue number
1191  * @bufnr: buffer number
1192  * @count: how many buffers to process
1193  * @aob: asynchronous operation block (outbound only)
1194  */
1195 int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
1196 	    int q_nr, unsigned int bufnr, unsigned int count, struct qaob *aob)
1197 {
1198 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1199 
1200 	if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1201 		return -EINVAL;
1202 
1203 	if (!irq_ptr)
1204 		return -ENODEV;
1205 
1206 	DBF_DEV_EVENT(DBF_INFO, irq_ptr,
1207 		      "do%02x b:%02x c:%02x", callflags, bufnr, count);
1208 
1209 	if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1210 		return -EIO;
1211 	if (!count)
1212 		return 0;
1213 	if (callflags & QDIO_FLAG_SYNC_INPUT)
1214 		return handle_inbound(irq_ptr->input_qs[q_nr], bufnr, count);
1215 	else if (callflags & QDIO_FLAG_SYNC_OUTPUT)
1216 		return handle_outbound(irq_ptr->output_qs[q_nr], bufnr, count, aob);
1217 	return -EINVAL;
1218 }
1219 EXPORT_SYMBOL_GPL(do_QDIO);
1220 
1221 /**
1222  * qdio_start_irq - enable interrupt processing for the device
1223  * @cdev: associated ccw_device for the qdio subchannel
1224  *
1225  * Return codes
1226  *   0 - success
1227  *   1 - irqs not started since new data is available
1228  */
1229 int qdio_start_irq(struct ccw_device *cdev)
1230 {
1231 	struct qdio_q *q;
1232 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1233 	unsigned int i;
1234 
1235 	if (!irq_ptr)
1236 		return -ENODEV;
1237 
1238 	for_each_input_queue(irq_ptr, q, i)
1239 		qdio_stop_polling(q);
1240 
1241 	clear_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state);
1242 
1243 	/*
1244 	 * We need to check again to not lose initiative after
1245 	 * resetting the ACK state.
1246 	 */
1247 	if (test_nonshared_ind(irq_ptr))
1248 		goto rescan;
1249 
1250 	for_each_input_queue(irq_ptr, q, i) {
1251 		if (!qdio_inbound_q_done(q, q->first_to_check))
1252 			goto rescan;
1253 	}
1254 
1255 	return 0;
1256 
1257 rescan:
1258 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1259 		return 0;
1260 	else
1261 		return 1;
1262 
1263 }
1264 EXPORT_SYMBOL(qdio_start_irq);
1265 
1266 static int __qdio_inspect_queue(struct qdio_q *q, unsigned int *bufnr,
1267 				unsigned int *error)
1268 {
1269 	unsigned int start = q->first_to_check;
1270 	int count;
1271 
1272 	*error = 0;
1273 	count = q->is_input_q ? get_inbound_buffer_frontier(q, start, error) :
1274 				get_outbound_buffer_frontier(q, start, error);
1275 	if (count == 0)
1276 		return 0;
1277 
1278 	*bufnr = start;
1279 
1280 	/* for the next time */
1281 	q->first_to_check = add_buf(start, count);
1282 
1283 	return count;
1284 }
1285 
1286 int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, bool is_input,
1287 		       unsigned int *bufnr, unsigned int *error)
1288 {
1289 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1290 	struct qdio_q *q;
1291 
1292 	if (!irq_ptr)
1293 		return -ENODEV;
1294 	q = is_input ? irq_ptr->input_qs[nr] : irq_ptr->output_qs[nr];
1295 
1296 	return __qdio_inspect_queue(q, bufnr, error);
1297 }
1298 EXPORT_SYMBOL_GPL(qdio_inspect_queue);
1299 
1300 /**
1301  * qdio_stop_irq - disable interrupt processing for the device
1302  * @cdev: associated ccw_device for the qdio subchannel
1303  *
1304  * Return codes
1305  *   0 - interrupts were already disabled
1306  *   1 - interrupts successfully disabled
1307  */
1308 int qdio_stop_irq(struct ccw_device *cdev)
1309 {
1310 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1311 
1312 	if (!irq_ptr)
1313 		return -ENODEV;
1314 
1315 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1316 		return 0;
1317 	else
1318 		return 1;
1319 }
1320 EXPORT_SYMBOL(qdio_stop_irq);
1321 
1322 static int __init init_QDIO(void)
1323 {
1324 	int rc;
1325 
1326 	rc = qdio_debug_init();
1327 	if (rc)
1328 		return rc;
1329 	rc = qdio_setup_init();
1330 	if (rc)
1331 		goto out_debug;
1332 	rc = qdio_thinint_init();
1333 	if (rc)
1334 		goto out_cache;
1335 	return 0;
1336 
1337 out_cache:
1338 	qdio_setup_exit();
1339 out_debug:
1340 	qdio_debug_exit();
1341 	return rc;
1342 }
1343 
1344 static void __exit exit_QDIO(void)
1345 {
1346 	qdio_thinint_exit();
1347 	qdio_setup_exit();
1348 	qdio_debug_exit();
1349 }
1350 
1351 module_init(init_QDIO);
1352 module_exit(exit_QDIO);
1353