xref: /openbmc/linux/drivers/s390/cio/qdio_main.c (revision fb574682)
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/timer.h>
14 #include <linux/delay.h>
15 #include <linux/gfp.h>
16 #include <linux/io.h>
17 #include <linux/atomic.h>
18 #include <asm/debug.h>
19 #include <asm/qdio.h>
20 #include <asm/ipl.h>
21 
22 #include "cio.h"
23 #include "css.h"
24 #include "device.h"
25 #include "qdio.h"
26 #include "qdio_debug.h"
27 
28 MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>,"\
29 	"Jan Glauber <jang@linux.vnet.ibm.com>");
30 MODULE_DESCRIPTION("QDIO base support");
31 MODULE_LICENSE("GPL");
32 
33 static inline int do_siga_sync(unsigned long schid,
34 			       unsigned int out_mask, unsigned int in_mask,
35 			       unsigned int fc)
36 {
37 	register unsigned long __fc asm ("0") = fc;
38 	register unsigned long __schid asm ("1") = schid;
39 	register unsigned long out asm ("2") = out_mask;
40 	register unsigned long in asm ("3") = in_mask;
41 	int cc;
42 
43 	asm volatile(
44 		"	siga	0\n"
45 		"	ipm	%0\n"
46 		"	srl	%0,28\n"
47 		: "=d" (cc)
48 		: "d" (__fc), "d" (__schid), "d" (out), "d" (in) : "cc");
49 	return cc;
50 }
51 
52 static inline int do_siga_input(unsigned long schid, unsigned int mask,
53 				unsigned int fc)
54 {
55 	register unsigned long __fc asm ("0") = fc;
56 	register unsigned long __schid asm ("1") = schid;
57 	register unsigned long __mask asm ("2") = mask;
58 	int cc;
59 
60 	asm volatile(
61 		"	siga	0\n"
62 		"	ipm	%0\n"
63 		"	srl	%0,28\n"
64 		: "=d" (cc)
65 		: "d" (__fc), "d" (__schid), "d" (__mask) : "cc");
66 	return cc;
67 }
68 
69 /**
70  * do_siga_output - perform SIGA-w/wt function
71  * @schid: subchannel id or in case of QEBSM the subchannel token
72  * @mask: which output queues to process
73  * @bb: busy bit indicator, set only if SIGA-w/wt could not access a buffer
74  * @fc: function code to perform
75  * @aob: asynchronous operation block
76  *
77  * Returns condition code.
78  * Note: For IQDC unicast queues only the highest priority queue is processed.
79  */
80 static inline int do_siga_output(unsigned long schid, unsigned long mask,
81 				 unsigned int *bb, unsigned int fc,
82 				 unsigned long aob)
83 {
84 	register unsigned long __fc asm("0") = fc;
85 	register unsigned long __schid asm("1") = schid;
86 	register unsigned long __mask asm("2") = mask;
87 	register unsigned long __aob asm("3") = aob;
88 	int cc;
89 
90 	asm volatile(
91 		"	siga	0\n"
92 		"	ipm	%0\n"
93 		"	srl	%0,28\n"
94 		: "=d" (cc), "+d" (__fc), "+d" (__aob)
95 		: "d" (__schid), "d" (__mask)
96 		: "cc");
97 	*bb = __fc >> 31;
98 	return cc;
99 }
100 
101 /**
102  * qdio_do_eqbs - extract buffer states for QEBSM
103  * @q: queue to manipulate
104  * @state: state of the extracted buffers
105  * @start: buffer number to start at
106  * @count: count of buffers to examine
107  * @auto_ack: automatically acknowledge buffers
108  *
109  * Returns the number of successfully extracted equal buffer states.
110  * Stops processing if a state is different from the last buffers state.
111  */
112 static int qdio_do_eqbs(struct qdio_q *q, unsigned char *state,
113 			int start, int count, int auto_ack)
114 {
115 	int tmp_count = count, tmp_start = start, nr = q->nr;
116 	unsigned int ccq = 0;
117 
118 	qperf_inc(q, eqbs);
119 
120 	if (!q->is_input_q)
121 		nr += q->irq_ptr->nr_input_qs;
122 again:
123 	ccq = do_eqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count,
124 		      auto_ack);
125 
126 	switch (ccq) {
127 	case 0:
128 	case 32:
129 		/* all done, or next buffer state different */
130 		return count - tmp_count;
131 	case 96:
132 		/* not all buffers processed */
133 		qperf_inc(q, eqbs_partial);
134 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "EQBS part:%02x",
135 			tmp_count);
136 		return count - tmp_count;
137 	case 97:
138 		/* no buffer processed */
139 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "EQBS again:%2d", ccq);
140 		goto again;
141 	default:
142 		DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
143 		DBF_ERROR("%4x EQBS ERROR", SCH_NO(q));
144 		DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
145 		q->handler(q->irq_ptr->cdev, QDIO_ERROR_GET_BUF_STATE, q->nr,
146 			   q->first_to_check, count, q->irq_ptr->int_parm);
147 		return 0;
148 	}
149 }
150 
151 /**
152  * qdio_do_sqbs - set buffer states for QEBSM
153  * @q: queue to manipulate
154  * @state: new state of the buffers
155  * @start: first buffer number to change
156  * @count: how many buffers to change
157  *
158  * Returns the number of successfully changed buffers.
159  * Does retrying until the specified count of buffer states is set or an
160  * error occurs.
161  */
162 static int qdio_do_sqbs(struct qdio_q *q, unsigned char state, int start,
163 			int count)
164 {
165 	unsigned int ccq = 0;
166 	int tmp_count = count, tmp_start = start;
167 	int nr = q->nr;
168 
169 	if (!count)
170 		return 0;
171 	qperf_inc(q, sqbs);
172 
173 	if (!q->is_input_q)
174 		nr += q->irq_ptr->nr_input_qs;
175 again:
176 	ccq = do_sqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count);
177 
178 	switch (ccq) {
179 	case 0:
180 	case 32:
181 		/* all done, or active buffer adapter-owned */
182 		WARN_ON_ONCE(tmp_count);
183 		return count - tmp_count;
184 	case 96:
185 		/* not all buffers processed */
186 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "SQBS again:%2d", ccq);
187 		qperf_inc(q, sqbs_partial);
188 		goto again;
189 	default:
190 		DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
191 		DBF_ERROR("%4x SQBS ERROR", SCH_NO(q));
192 		DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
193 		q->handler(q->irq_ptr->cdev, QDIO_ERROR_SET_BUF_STATE, q->nr,
194 			   q->first_to_check, count, q->irq_ptr->int_parm);
195 		return 0;
196 	}
197 }
198 
199 /*
200  * Returns number of examined buffers and their common state in *state.
201  * Requested number of buffers-to-examine must be > 0.
202  */
203 static inline int get_buf_states(struct qdio_q *q, unsigned int bufnr,
204 				 unsigned char *state, unsigned int count,
205 				 int auto_ack, int merge_pending)
206 {
207 	unsigned char __state = 0;
208 	int i = 1;
209 
210 	if (is_qebsm(q))
211 		return qdio_do_eqbs(q, state, bufnr, count, auto_ack);
212 
213 	/* get initial state: */
214 	__state = q->slsb.val[bufnr];
215 
216 	/* Bail out early if there is no work on the queue: */
217 	if (__state & SLSB_OWNER_CU)
218 		goto out;
219 
220 	if (merge_pending && __state == SLSB_P_OUTPUT_PENDING)
221 		__state = SLSB_P_OUTPUT_EMPTY;
222 
223 	for (; i < count; i++) {
224 		bufnr = next_buf(bufnr);
225 
226 		/* merge PENDING into EMPTY: */
227 		if (merge_pending &&
228 		    q->slsb.val[bufnr] == SLSB_P_OUTPUT_PENDING &&
229 		    __state == SLSB_P_OUTPUT_EMPTY)
230 			continue;
231 
232 		/* stop if next state differs from initial state: */
233 		if (q->slsb.val[bufnr] != __state)
234 			break;
235 	}
236 
237 out:
238 	*state = __state;
239 	return i;
240 }
241 
242 static inline int get_buf_state(struct qdio_q *q, unsigned int bufnr,
243 				unsigned char *state, int auto_ack)
244 {
245 	return get_buf_states(q, bufnr, state, 1, auto_ack, 0);
246 }
247 
248 /* wrap-around safe setting of slsb states, returns number of changed buffers */
249 static inline int set_buf_states(struct qdio_q *q, int bufnr,
250 				 unsigned char state, int count)
251 {
252 	int i;
253 
254 	if (is_qebsm(q))
255 		return qdio_do_sqbs(q, state, bufnr, count);
256 
257 	for (i = 0; i < count; i++) {
258 		xchg(&q->slsb.val[bufnr], state);
259 		bufnr = next_buf(bufnr);
260 	}
261 	return count;
262 }
263 
264 static inline int set_buf_state(struct qdio_q *q, int bufnr,
265 				unsigned char state)
266 {
267 	return set_buf_states(q, bufnr, state, 1);
268 }
269 
270 /* set slsb states to initial state */
271 static void qdio_init_buf_states(struct qdio_irq *irq_ptr)
272 {
273 	struct qdio_q *q;
274 	int i;
275 
276 	for_each_input_queue(irq_ptr, q, i)
277 		set_buf_states(q, 0, SLSB_P_INPUT_NOT_INIT,
278 			       QDIO_MAX_BUFFERS_PER_Q);
279 	for_each_output_queue(irq_ptr, q, i)
280 		set_buf_states(q, 0, SLSB_P_OUTPUT_NOT_INIT,
281 			       QDIO_MAX_BUFFERS_PER_Q);
282 }
283 
284 static inline int qdio_siga_sync(struct qdio_q *q, unsigned int output,
285 			  unsigned int input)
286 {
287 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
288 	unsigned int fc = QDIO_SIGA_SYNC;
289 	int cc;
290 
291 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-s:%1d", q->nr);
292 	qperf_inc(q, siga_sync);
293 
294 	if (is_qebsm(q)) {
295 		schid = q->irq_ptr->sch_token;
296 		fc |= QDIO_SIGA_QEBSM_FLAG;
297 	}
298 
299 	cc = do_siga_sync(schid, output, input, fc);
300 	if (unlikely(cc))
301 		DBF_ERROR("%4x SIGA-S:%2d", SCH_NO(q), cc);
302 	return (cc) ? -EIO : 0;
303 }
304 
305 static inline int qdio_siga_sync_q(struct qdio_q *q)
306 {
307 	if (q->is_input_q)
308 		return qdio_siga_sync(q, 0, q->mask);
309 	else
310 		return qdio_siga_sync(q, q->mask, 0);
311 }
312 
313 static int qdio_siga_output(struct qdio_q *q, unsigned int count,
314 			    unsigned int *busy_bit, unsigned long aob)
315 {
316 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
317 	unsigned int fc = QDIO_SIGA_WRITE;
318 	u64 start_time = 0;
319 	int retries = 0, cc;
320 
321 	if (queue_type(q) == QDIO_IQDIO_QFMT && !multicast_outbound(q)) {
322 		if (count > 1)
323 			fc = QDIO_SIGA_WRITEM;
324 		else if (aob)
325 			fc = QDIO_SIGA_WRITEQ;
326 	}
327 
328 	if (is_qebsm(q)) {
329 		schid = q->irq_ptr->sch_token;
330 		fc |= QDIO_SIGA_QEBSM_FLAG;
331 	}
332 again:
333 	cc = do_siga_output(schid, q->mask, busy_bit, fc, aob);
334 
335 	/* hipersocket busy condition */
336 	if (unlikely(*busy_bit)) {
337 		retries++;
338 
339 		if (!start_time) {
340 			start_time = get_tod_clock_fast();
341 			goto again;
342 		}
343 		if (get_tod_clock_fast() - start_time < QDIO_BUSY_BIT_PATIENCE)
344 			goto again;
345 	}
346 	if (retries) {
347 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr,
348 			      "%4x cc2 BB1:%1d", SCH_NO(q), q->nr);
349 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "count:%u", retries);
350 	}
351 	return cc;
352 }
353 
354 static inline int qdio_siga_input(struct qdio_q *q)
355 {
356 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
357 	unsigned int fc = QDIO_SIGA_READ;
358 	int cc;
359 
360 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-r:%1d", q->nr);
361 	qperf_inc(q, siga_read);
362 
363 	if (is_qebsm(q)) {
364 		schid = q->irq_ptr->sch_token;
365 		fc |= QDIO_SIGA_QEBSM_FLAG;
366 	}
367 
368 	cc = do_siga_input(schid, q->mask, fc);
369 	if (unlikely(cc))
370 		DBF_ERROR("%4x SIGA-R:%2d", SCH_NO(q), cc);
371 	return (cc) ? -EIO : 0;
372 }
373 
374 #define qdio_siga_sync_out(q) qdio_siga_sync(q, ~0U, 0)
375 #define qdio_siga_sync_all(q) qdio_siga_sync(q, ~0U, ~0U)
376 
377 static inline void qdio_sync_queues(struct qdio_q *q)
378 {
379 	/* PCI capable outbound queues will also be scanned so sync them too */
380 	if (pci_out_supported(q->irq_ptr))
381 		qdio_siga_sync_all(q);
382 	else
383 		qdio_siga_sync_q(q);
384 }
385 
386 int debug_get_buf_state(struct qdio_q *q, unsigned int bufnr,
387 			unsigned char *state)
388 {
389 	if (need_siga_sync(q))
390 		qdio_siga_sync_q(q);
391 	return get_buf_state(q, bufnr, state, 0);
392 }
393 
394 static inline void qdio_stop_polling(struct qdio_q *q)
395 {
396 	if (!q->u.in.ack_count)
397 		return;
398 
399 	qperf_inc(q, stop_polling);
400 
401 	/* show the card that we are not polling anymore */
402 	set_buf_states(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT,
403 		       q->u.in.ack_count);
404 	q->u.in.ack_count = 0;
405 }
406 
407 static inline void account_sbals(struct qdio_q *q, unsigned int count)
408 {
409 	int pos;
410 
411 	q->q_stats.nr_sbal_total += count;
412 	if (count == QDIO_MAX_BUFFERS_MASK) {
413 		q->q_stats.nr_sbals[7]++;
414 		return;
415 	}
416 	pos = ilog2(count);
417 	q->q_stats.nr_sbals[pos]++;
418 }
419 
420 static void process_buffer_error(struct qdio_q *q, unsigned int start,
421 				 int count)
422 {
423 	q->qdio_error = QDIO_ERROR_SLSB_STATE;
424 
425 	/* special handling for no target buffer empty */
426 	if (queue_type(q) == QDIO_IQDIO_QFMT && !q->is_input_q &&
427 	    q->sbal[start]->element[15].sflags == 0x10) {
428 		qperf_inc(q, target_full);
429 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "OUTFULL FTC:%02x", start);
430 		return;
431 	}
432 
433 	DBF_ERROR("%4x BUF ERROR", SCH_NO(q));
434 	DBF_ERROR((q->is_input_q) ? "IN:%2d" : "OUT:%2d", q->nr);
435 	DBF_ERROR("FTC:%3d C:%3d", start, count);
436 	DBF_ERROR("F14:%2x F15:%2x",
437 		  q->sbal[start]->element[14].sflags,
438 		  q->sbal[start]->element[15].sflags);
439 }
440 
441 static inline void inbound_handle_work(struct qdio_q *q, unsigned int start,
442 				       int count, bool auto_ack)
443 {
444 	int new;
445 
446 	if (auto_ack) {
447 		if (!q->u.in.ack_count) {
448 			q->u.in.ack_count = count;
449 			q->u.in.ack_start = start;
450 			return;
451 		}
452 
453 		/* delete the previous ACK's */
454 		set_buf_states(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT,
455 			       q->u.in.ack_count);
456 		q->u.in.ack_count = count;
457 		q->u.in.ack_start = start;
458 		return;
459 	}
460 
461 	/*
462 	 * ACK the newest buffer. The ACK will be removed in qdio_stop_polling
463 	 * or by the next inbound run.
464 	 */
465 	new = add_buf(start, count - 1);
466 	set_buf_state(q, new, SLSB_P_INPUT_ACK);
467 
468 	/* delete the previous ACKs */
469 	if (q->u.in.ack_count)
470 		set_buf_states(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT,
471 			       q->u.in.ack_count);
472 
473 	q->u.in.ack_count = 1;
474 	q->u.in.ack_start = new;
475 	count--;
476 	if (!count)
477 		return;
478 	/* need to change ALL buffers to get more interrupts */
479 	set_buf_states(q, start, SLSB_P_INPUT_NOT_INIT, count);
480 }
481 
482 static int get_inbound_buffer_frontier(struct qdio_q *q, unsigned int start)
483 {
484 	unsigned char state = 0;
485 	int count;
486 
487 	q->timestamp = get_tod_clock_fast();
488 
489 	/*
490 	 * Don't check 128 buffers, as otherwise qdio_inbound_q_moved
491 	 * would return 0.
492 	 */
493 	count = min(atomic_read(&q->nr_buf_used), QDIO_MAX_BUFFERS_MASK);
494 	if (!count)
495 		return 0;
496 
497 	/*
498 	 * No siga sync here, as a PCI or we after a thin interrupt
499 	 * already sync'ed the queues.
500 	 */
501 	count = get_buf_states(q, start, &state, count, 1, 0);
502 	if (!count)
503 		return 0;
504 
505 	switch (state) {
506 	case SLSB_P_INPUT_PRIMED:
507 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in prim:%1d %02x", q->nr,
508 			      count);
509 
510 		inbound_handle_work(q, start, count, is_qebsm(q));
511 		if (atomic_sub_return(count, &q->nr_buf_used) == 0)
512 			qperf_inc(q, inbound_queue_full);
513 		if (q->irq_ptr->perf_stat_enabled)
514 			account_sbals(q, count);
515 		return count;
516 	case SLSB_P_INPUT_ERROR:
517 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in err:%1d %02x", q->nr,
518 			      count);
519 
520 		process_buffer_error(q, start, count);
521 		inbound_handle_work(q, start, count, false);
522 		if (atomic_sub_return(count, &q->nr_buf_used) == 0)
523 			qperf_inc(q, inbound_queue_full);
524 		if (q->irq_ptr->perf_stat_enabled)
525 			account_sbals_error(q, count);
526 		return count;
527 	case SLSB_CU_INPUT_EMPTY:
528 	case SLSB_P_INPUT_NOT_INIT:
529 	case SLSB_P_INPUT_ACK:
530 		if (q->irq_ptr->perf_stat_enabled)
531 			q->q_stats.nr_sbal_nop++;
532 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in nop:%1d %#02x",
533 			      q->nr, start);
534 		return 0;
535 	default:
536 		WARN_ON_ONCE(1);
537 		return 0;
538 	}
539 }
540 
541 static int qdio_inbound_q_moved(struct qdio_q *q, unsigned int start)
542 {
543 	int count;
544 
545 	count = get_inbound_buffer_frontier(q, start);
546 
547 	if (count && !is_thinint_irq(q->irq_ptr) && MACHINE_IS_LPAR)
548 		q->u.in.timestamp = get_tod_clock();
549 
550 	return count;
551 }
552 
553 static inline int qdio_inbound_q_done(struct qdio_q *q, unsigned int start)
554 {
555 	unsigned char state = 0;
556 
557 	if (!atomic_read(&q->nr_buf_used))
558 		return 1;
559 
560 	if (need_siga_sync(q))
561 		qdio_siga_sync_q(q);
562 	get_buf_state(q, start, &state, 0);
563 
564 	if (state == SLSB_P_INPUT_PRIMED || state == SLSB_P_INPUT_ERROR)
565 		/* more work coming */
566 		return 0;
567 
568 	if (is_thinint_irq(q->irq_ptr))
569 		return 1;
570 
571 	/* don't poll under z/VM */
572 	if (MACHINE_IS_VM)
573 		return 1;
574 
575 	/*
576 	 * At this point we know, that inbound first_to_check
577 	 * has (probably) not moved (see qdio_inbound_processing).
578 	 */
579 	if (get_tod_clock_fast() > q->u.in.timestamp + QDIO_INPUT_THRESHOLD) {
580 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in done:%02x", start);
581 		return 1;
582 	} else
583 		return 0;
584 }
585 
586 static inline void qdio_handle_aobs(struct qdio_q *q, int start, int count)
587 {
588 	unsigned char state = 0;
589 	int j, b = start;
590 
591 	for (j = 0; j < count; ++j) {
592 		get_buf_state(q, b, &state, 0);
593 		if (state == SLSB_P_OUTPUT_PENDING) {
594 			struct qaob *aob = q->u.out.aobs[b];
595 			if (aob == NULL)
596 				continue;
597 
598 			q->u.out.sbal_state[b].flags |=
599 				QDIO_OUTBUF_STATE_FLAG_PENDING;
600 			q->u.out.aobs[b] = NULL;
601 		}
602 		b = next_buf(b);
603 	}
604 }
605 
606 static inline unsigned long qdio_aob_for_buffer(struct qdio_output_q *q,
607 					int bufnr)
608 {
609 	unsigned long phys_aob = 0;
610 
611 	if (!q->aobs[bufnr]) {
612 		struct qaob *aob = qdio_allocate_aob();
613 		q->aobs[bufnr] = aob;
614 	}
615 	if (q->aobs[bufnr]) {
616 		q->aobs[bufnr]->user1 = (u64) q->sbal_state[bufnr].user;
617 		phys_aob = virt_to_phys(q->aobs[bufnr]);
618 		WARN_ON_ONCE(phys_aob & 0xFF);
619 	}
620 
621 	q->sbal_state[bufnr].flags = 0;
622 	return phys_aob;
623 }
624 
625 static void qdio_kick_handler(struct qdio_q *q, unsigned int start,
626 			      unsigned int count)
627 {
628 	if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
629 		return;
630 
631 	if (q->is_input_q) {
632 		qperf_inc(q, inbound_handler);
633 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "kih s:%02x c:%02x", start, count);
634 	} else {
635 		qperf_inc(q, outbound_handler);
636 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "koh: s:%02x c:%02x",
637 			      start, count);
638 	}
639 
640 	q->handler(q->irq_ptr->cdev, q->qdio_error, q->nr, start, count,
641 		   q->irq_ptr->int_parm);
642 
643 	/* for the next time */
644 	q->qdio_error = 0;
645 }
646 
647 static inline int qdio_tasklet_schedule(struct qdio_q *q)
648 {
649 	if (likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE)) {
650 		tasklet_schedule(&q->tasklet);
651 		return 0;
652 	}
653 	return -EPERM;
654 }
655 
656 static void __qdio_inbound_processing(struct qdio_q *q)
657 {
658 	unsigned int start = q->first_to_check;
659 	int count;
660 
661 	qperf_inc(q, tasklet_inbound);
662 
663 	count = qdio_inbound_q_moved(q, start);
664 	if (count == 0)
665 		return;
666 
667 	qdio_kick_handler(q, start, count);
668 	start = add_buf(start, count);
669 	q->first_to_check = start;
670 
671 	if (!qdio_inbound_q_done(q, start)) {
672 		/* means poll time is not yet over */
673 		qperf_inc(q, tasklet_inbound_resched);
674 		if (!qdio_tasklet_schedule(q))
675 			return;
676 	}
677 
678 	qdio_stop_polling(q);
679 	/*
680 	 * We need to check again to not lose initiative after
681 	 * resetting the ACK state.
682 	 */
683 	if (!qdio_inbound_q_done(q, start)) {
684 		qperf_inc(q, tasklet_inbound_resched2);
685 		qdio_tasklet_schedule(q);
686 	}
687 }
688 
689 void qdio_inbound_processing(unsigned long data)
690 {
691 	struct qdio_q *q = (struct qdio_q *)data;
692 	__qdio_inbound_processing(q);
693 }
694 
695 static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start)
696 {
697 	unsigned char state = 0;
698 	int count;
699 
700 	q->timestamp = get_tod_clock_fast();
701 
702 	if (need_siga_sync(q))
703 		if (((queue_type(q) != QDIO_IQDIO_QFMT) &&
704 		    !pci_out_supported(q->irq_ptr)) ||
705 		    (queue_type(q) == QDIO_IQDIO_QFMT &&
706 		    multicast_outbound(q)))
707 			qdio_siga_sync_q(q);
708 
709 	count = atomic_read(&q->nr_buf_used);
710 	if (!count)
711 		return 0;
712 
713 	count = get_buf_states(q, start, &state, count, 0, q->u.out.use_cq);
714 	if (!count)
715 		return 0;
716 
717 	switch (state) {
718 	case SLSB_P_OUTPUT_EMPTY:
719 	case SLSB_P_OUTPUT_PENDING:
720 		/* the adapter got it */
721 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
722 			"out empty:%1d %02x", q->nr, count);
723 
724 		atomic_sub(count, &q->nr_buf_used);
725 		if (q->irq_ptr->perf_stat_enabled)
726 			account_sbals(q, count);
727 		return count;
728 	case SLSB_P_OUTPUT_ERROR:
729 		process_buffer_error(q, start, count);
730 		atomic_sub(count, &q->nr_buf_used);
731 		if (q->irq_ptr->perf_stat_enabled)
732 			account_sbals_error(q, count);
733 		return count;
734 	case SLSB_CU_OUTPUT_PRIMED:
735 		/* the adapter has not fetched the output yet */
736 		if (q->irq_ptr->perf_stat_enabled)
737 			q->q_stats.nr_sbal_nop++;
738 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out primed:%1d",
739 			      q->nr);
740 		return 0;
741 	case SLSB_P_OUTPUT_NOT_INIT:
742 	case SLSB_P_OUTPUT_HALTED:
743 		return 0;
744 	default:
745 		WARN_ON_ONCE(1);
746 		return 0;
747 	}
748 }
749 
750 /* all buffers processed? */
751 static inline int qdio_outbound_q_done(struct qdio_q *q)
752 {
753 	return atomic_read(&q->nr_buf_used) == 0;
754 }
755 
756 static inline int qdio_outbound_q_moved(struct qdio_q *q, unsigned int start)
757 {
758 	int count;
759 
760 	count = get_outbound_buffer_frontier(q, start);
761 
762 	if (count) {
763 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out moved:%1d", q->nr);
764 		if (q->u.out.use_cq)
765 			qdio_handle_aobs(q, start, count);
766 	}
767 
768 	return count;
769 }
770 
771 static int qdio_kick_outbound_q(struct qdio_q *q, unsigned int count,
772 				unsigned long aob)
773 {
774 	int retries = 0, cc;
775 	unsigned int busy_bit;
776 
777 	if (!need_siga_out(q))
778 		return 0;
779 
780 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w:%1d", q->nr);
781 retry:
782 	qperf_inc(q, siga_write);
783 
784 	cc = qdio_siga_output(q, count, &busy_bit, aob);
785 	switch (cc) {
786 	case 0:
787 		break;
788 	case 2:
789 		if (busy_bit) {
790 			while (++retries < QDIO_BUSY_BIT_RETRIES) {
791 				mdelay(QDIO_BUSY_BIT_RETRY_DELAY);
792 				goto retry;
793 			}
794 			DBF_ERROR("%4x cc2 BBC:%1d", SCH_NO(q), q->nr);
795 			cc = -EBUSY;
796 		} else {
797 			DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w cc2:%1d", q->nr);
798 			cc = -ENOBUFS;
799 		}
800 		break;
801 	case 1:
802 	case 3:
803 		DBF_ERROR("%4x SIGA-W:%1d", SCH_NO(q), cc);
804 		cc = -EIO;
805 		break;
806 	}
807 	if (retries) {
808 		DBF_ERROR("%4x cc2 BB2:%1d", SCH_NO(q), q->nr);
809 		DBF_ERROR("count:%u", retries);
810 	}
811 	return cc;
812 }
813 
814 static void __qdio_outbound_processing(struct qdio_q *q)
815 {
816 	unsigned int start = q->first_to_check;
817 	int count;
818 
819 	qperf_inc(q, tasklet_outbound);
820 	WARN_ON_ONCE(atomic_read(&q->nr_buf_used) < 0);
821 
822 	count = qdio_outbound_q_moved(q, start);
823 	if (count) {
824 		q->first_to_check = add_buf(start, count);
825 		qdio_kick_handler(q, start, count);
826 	}
827 
828 	if (queue_type(q) == QDIO_ZFCP_QFMT && !pci_out_supported(q->irq_ptr) &&
829 	    !qdio_outbound_q_done(q))
830 		goto sched;
831 
832 	if (q->u.out.pci_out_enabled)
833 		return;
834 
835 	/*
836 	 * Now we know that queue type is either qeth without pci enabled
837 	 * or HiperSockets. Make sure buffer switch from PRIMED to EMPTY
838 	 * is noticed and outbound_handler is called after some time.
839 	 */
840 	if (qdio_outbound_q_done(q))
841 		del_timer_sync(&q->u.out.timer);
842 	else
843 		if (!timer_pending(&q->u.out.timer) &&
844 		    likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
845 			mod_timer(&q->u.out.timer, jiffies + 10 * HZ);
846 	return;
847 
848 sched:
849 	qdio_tasklet_schedule(q);
850 }
851 
852 /* outbound tasklet */
853 void qdio_outbound_processing(unsigned long data)
854 {
855 	struct qdio_q *q = (struct qdio_q *)data;
856 	__qdio_outbound_processing(q);
857 }
858 
859 void qdio_outbound_timer(struct timer_list *t)
860 {
861 	struct qdio_q *q = from_timer(q, t, u.out.timer);
862 
863 	qdio_tasklet_schedule(q);
864 }
865 
866 static inline void qdio_check_outbound_pci_queues(struct qdio_irq *irq)
867 {
868 	struct qdio_q *out;
869 	int i;
870 
871 	if (!pci_out_supported(irq) || !irq->scan_threshold)
872 		return;
873 
874 	for_each_output_queue(irq, out, i)
875 		if (!qdio_outbound_q_done(out))
876 			qdio_tasklet_schedule(out);
877 }
878 
879 void tiqdio_inbound_processing(unsigned long data)
880 {
881 	struct qdio_q *q = (struct qdio_q *)data;
882 
883 	if (need_siga_sync(q) && need_siga_sync_after_ai(q))
884 		qdio_sync_queues(q);
885 
886 	/* The interrupt could be caused by a PCI request: */
887 	qdio_check_outbound_pci_queues(q->irq_ptr);
888 
889 	__qdio_inbound_processing(q);
890 }
891 
892 static inline void qdio_set_state(struct qdio_irq *irq_ptr,
893 				  enum qdio_irq_states state)
894 {
895 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "newstate: %1d", state);
896 
897 	irq_ptr->state = state;
898 	mb();
899 }
900 
901 static void qdio_irq_check_sense(struct qdio_irq *irq_ptr, struct irb *irb)
902 {
903 	if (irb->esw.esw0.erw.cons) {
904 		DBF_ERROR("%4x sense:", irq_ptr->schid.sch_no);
905 		DBF_ERROR_HEX(irb, 64);
906 		DBF_ERROR_HEX(irb->ecw, 64);
907 	}
908 }
909 
910 /* PCI interrupt handler */
911 static void qdio_int_handler_pci(struct qdio_irq *irq_ptr)
912 {
913 	int i;
914 	struct qdio_q *q;
915 
916 	if (unlikely(irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
917 		return;
918 
919 	if (irq_ptr->irq_poll) {
920 		if (!test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
921 			irq_ptr->irq_poll(irq_ptr->cdev, irq_ptr->int_parm);
922 		else
923 			QDIO_PERF_STAT_INC(irq_ptr, int_discarded);
924 	} else {
925 		for_each_input_queue(irq_ptr, q, i)
926 			tasklet_schedule(&q->tasklet);
927 	}
928 
929 	if (!pci_out_supported(irq_ptr) || !irq_ptr->scan_threshold)
930 		return;
931 
932 	for_each_output_queue(irq_ptr, q, i) {
933 		if (qdio_outbound_q_done(q))
934 			continue;
935 		if (need_siga_sync(q) && need_siga_sync_out_after_pci(q))
936 			qdio_siga_sync_q(q);
937 		qdio_tasklet_schedule(q);
938 	}
939 }
940 
941 static void qdio_handle_activate_check(struct ccw_device *cdev,
942 				unsigned long intparm, int cstat, int dstat)
943 {
944 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
945 	struct qdio_q *q;
946 
947 	DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
948 	DBF_ERROR("intp :%lx", intparm);
949 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
950 
951 	if (irq_ptr->nr_input_qs) {
952 		q = irq_ptr->input_qs[0];
953 	} else if (irq_ptr->nr_output_qs) {
954 		q = irq_ptr->output_qs[0];
955 	} else {
956 		dump_stack();
957 		goto no_handler;
958 	}
959 
960 	q->handler(q->irq_ptr->cdev, QDIO_ERROR_ACTIVATE,
961 		   q->nr, q->first_to_check, 0, irq_ptr->int_parm);
962 no_handler:
963 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
964 	/*
965 	 * In case of z/VM LGR (Live Guest Migration) QDIO recovery will happen.
966 	 * Therefore we call the LGR detection function here.
967 	 */
968 	lgr_info_log();
969 }
970 
971 static void qdio_establish_handle_irq(struct ccw_device *cdev, int cstat,
972 				      int dstat)
973 {
974 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
975 
976 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qest irq");
977 
978 	if (cstat)
979 		goto error;
980 	if (dstat & ~(DEV_STAT_DEV_END | DEV_STAT_CHN_END))
981 		goto error;
982 	if (!(dstat & DEV_STAT_DEV_END))
983 		goto error;
984 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ESTABLISHED);
985 	return;
986 
987 error:
988 	DBF_ERROR("%4x EQ:error", irq_ptr->schid.sch_no);
989 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
990 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
991 }
992 
993 /* qdio interrupt handler */
994 void qdio_int_handler(struct ccw_device *cdev, unsigned long intparm,
995 		      struct irb *irb)
996 {
997 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
998 	struct subchannel_id schid;
999 	int cstat, dstat;
1000 
1001 	if (!intparm || !irq_ptr) {
1002 		ccw_device_get_schid(cdev, &schid);
1003 		DBF_ERROR("qint:%4x", schid.sch_no);
1004 		return;
1005 	}
1006 
1007 	if (irq_ptr->perf_stat_enabled)
1008 		irq_ptr->perf_stat.qdio_int++;
1009 
1010 	if (IS_ERR(irb)) {
1011 		DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
1012 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
1013 		wake_up(&cdev->private->wait_q);
1014 		return;
1015 	}
1016 	qdio_irq_check_sense(irq_ptr, irb);
1017 	cstat = irb->scsw.cmd.cstat;
1018 	dstat = irb->scsw.cmd.dstat;
1019 
1020 	switch (irq_ptr->state) {
1021 	case QDIO_IRQ_STATE_INACTIVE:
1022 		qdio_establish_handle_irq(cdev, cstat, dstat);
1023 		break;
1024 	case QDIO_IRQ_STATE_CLEANUP:
1025 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1026 		break;
1027 	case QDIO_IRQ_STATE_ESTABLISHED:
1028 	case QDIO_IRQ_STATE_ACTIVE:
1029 		if (cstat & SCHN_STAT_PCI) {
1030 			qdio_int_handler_pci(irq_ptr);
1031 			return;
1032 		}
1033 		if (cstat || dstat)
1034 			qdio_handle_activate_check(cdev, intparm, cstat,
1035 						   dstat);
1036 		break;
1037 	case QDIO_IRQ_STATE_STOPPED:
1038 		break;
1039 	default:
1040 		WARN_ON_ONCE(1);
1041 	}
1042 	wake_up(&cdev->private->wait_q);
1043 }
1044 
1045 /**
1046  * qdio_get_ssqd_desc - get qdio subchannel description
1047  * @cdev: ccw device to get description for
1048  * @data: where to store the ssqd
1049  *
1050  * Returns 0 or an error code. The results of the chsc are stored in the
1051  * specified structure.
1052  */
1053 int qdio_get_ssqd_desc(struct ccw_device *cdev,
1054 		       struct qdio_ssqd_desc *data)
1055 {
1056 	struct subchannel_id schid;
1057 
1058 	if (!cdev || !cdev->private)
1059 		return -EINVAL;
1060 
1061 	ccw_device_get_schid(cdev, &schid);
1062 	DBF_EVENT("get ssqd:%4x", schid.sch_no);
1063 	return qdio_setup_get_ssqd(NULL, &schid, data);
1064 }
1065 EXPORT_SYMBOL_GPL(qdio_get_ssqd_desc);
1066 
1067 static void qdio_shutdown_queues(struct qdio_irq *irq_ptr)
1068 {
1069 	struct qdio_q *q;
1070 	int i;
1071 
1072 	for_each_input_queue(irq_ptr, q, i)
1073 		tasklet_kill(&q->tasklet);
1074 
1075 	for_each_output_queue(irq_ptr, q, i) {
1076 		del_timer_sync(&q->u.out.timer);
1077 		tasklet_kill(&q->tasklet);
1078 	}
1079 }
1080 
1081 /**
1082  * qdio_shutdown - shut down a qdio subchannel
1083  * @cdev: associated ccw device
1084  * @how: use halt or clear to shutdown
1085  */
1086 int qdio_shutdown(struct ccw_device *cdev, int how)
1087 {
1088 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1089 	struct subchannel_id schid;
1090 	int rc;
1091 
1092 	if (!irq_ptr)
1093 		return -ENODEV;
1094 
1095 	WARN_ON_ONCE(irqs_disabled());
1096 	ccw_device_get_schid(cdev, &schid);
1097 	DBF_EVENT("qshutdown:%4x", schid.sch_no);
1098 
1099 	mutex_lock(&irq_ptr->setup_mutex);
1100 	/*
1101 	 * Subchannel was already shot down. We cannot prevent being called
1102 	 * twice since cio may trigger a shutdown asynchronously.
1103 	 */
1104 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1105 		mutex_unlock(&irq_ptr->setup_mutex);
1106 		return 0;
1107 	}
1108 
1109 	/*
1110 	 * Indicate that the device is going down. Scheduling the queue
1111 	 * tasklets is forbidden from here on.
1112 	 */
1113 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
1114 
1115 	tiqdio_remove_device(irq_ptr);
1116 	qdio_shutdown_queues(irq_ptr);
1117 	qdio_shutdown_debug_entries(irq_ptr);
1118 
1119 	/* cleanup subchannel */
1120 	spin_lock_irq(get_ccwdev_lock(cdev));
1121 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_CLEANUP);
1122 	if (how & QDIO_FLAG_CLEANUP_USING_CLEAR)
1123 		rc = ccw_device_clear(cdev, QDIO_DOING_CLEANUP);
1124 	else
1125 		/* default behaviour is halt */
1126 		rc = ccw_device_halt(cdev, QDIO_DOING_CLEANUP);
1127 	spin_unlock_irq(get_ccwdev_lock(cdev));
1128 	if (rc) {
1129 		DBF_ERROR("%4x SHUTD ERR", irq_ptr->schid.sch_no);
1130 		DBF_ERROR("rc:%4d", rc);
1131 		goto no_cleanup;
1132 	}
1133 
1134 	wait_event_interruptible_timeout(cdev->private->wait_q,
1135 		irq_ptr->state == QDIO_IRQ_STATE_INACTIVE ||
1136 		irq_ptr->state == QDIO_IRQ_STATE_ERR,
1137 		10 * HZ);
1138 
1139 no_cleanup:
1140 	qdio_shutdown_thinint(irq_ptr);
1141 	qdio_shutdown_irq(irq_ptr);
1142 
1143 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1144 	mutex_unlock(&irq_ptr->setup_mutex);
1145 	if (rc)
1146 		return rc;
1147 	return 0;
1148 }
1149 EXPORT_SYMBOL_GPL(qdio_shutdown);
1150 
1151 /**
1152  * qdio_free - free data structures for a qdio subchannel
1153  * @cdev: associated ccw device
1154  */
1155 int qdio_free(struct ccw_device *cdev)
1156 {
1157 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1158 	struct subchannel_id schid;
1159 
1160 	if (!irq_ptr)
1161 		return -ENODEV;
1162 
1163 	ccw_device_get_schid(cdev, &schid);
1164 	DBF_EVENT("qfree:%4x", schid.sch_no);
1165 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf abandoned");
1166 	mutex_lock(&irq_ptr->setup_mutex);
1167 
1168 	irq_ptr->debug_area = NULL;
1169 	cdev->private->qdio_data = NULL;
1170 	mutex_unlock(&irq_ptr->setup_mutex);
1171 
1172 	qdio_free_async_data(irq_ptr);
1173 	qdio_free_queues(irq_ptr);
1174 	free_page((unsigned long) irq_ptr->qdr);
1175 	free_page(irq_ptr->chsc_page);
1176 	free_page((unsigned long) irq_ptr);
1177 	return 0;
1178 }
1179 EXPORT_SYMBOL_GPL(qdio_free);
1180 
1181 /**
1182  * qdio_allocate - allocate qdio queues and associated data
1183  * @cdev: associated ccw device
1184  * @no_input_qs: allocate this number of Input Queues
1185  * @no_output_qs: allocate this number of Output Queues
1186  */
1187 int qdio_allocate(struct ccw_device *cdev, unsigned int no_input_qs,
1188 		  unsigned int no_output_qs)
1189 {
1190 	struct subchannel_id schid;
1191 	struct qdio_irq *irq_ptr;
1192 	int rc = -ENOMEM;
1193 
1194 	ccw_device_get_schid(cdev, &schid);
1195 	DBF_EVENT("qallocate:%4x", schid.sch_no);
1196 
1197 	if (no_input_qs > QDIO_MAX_QUEUES_PER_IRQ ||
1198 	    no_output_qs > QDIO_MAX_QUEUES_PER_IRQ)
1199 		return -EINVAL;
1200 
1201 	/* irq_ptr must be in GFP_DMA since it contains ccw1.cda */
1202 	irq_ptr = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1203 	if (!irq_ptr)
1204 		return -ENOMEM;
1205 
1206 	irq_ptr->cdev = cdev;
1207 	mutex_init(&irq_ptr->setup_mutex);
1208 	if (qdio_allocate_dbf(irq_ptr))
1209 		goto err_dbf;
1210 
1211 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "alloc niq:%1u noq:%1u", no_input_qs,
1212 		      no_output_qs);
1213 
1214 	/*
1215 	 * Allocate a page for the chsc calls in qdio_establish.
1216 	 * Must be pre-allocated since a zfcp recovery will call
1217 	 * qdio_establish. In case of low memory and swap on a zfcp disk
1218 	 * we may not be able to allocate memory otherwise.
1219 	 */
1220 	irq_ptr->chsc_page = get_zeroed_page(GFP_KERNEL);
1221 	if (!irq_ptr->chsc_page)
1222 		goto err_chsc;
1223 
1224 	/* qdr is used in ccw1.cda which is u32 */
1225 	irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1226 	if (!irq_ptr->qdr)
1227 		goto err_qdr;
1228 
1229 	rc = qdio_allocate_qs(irq_ptr, no_input_qs, no_output_qs);
1230 	if (rc)
1231 		goto err_queues;
1232 
1233 	INIT_LIST_HEAD(&irq_ptr->entry);
1234 	cdev->private->qdio_data = irq_ptr;
1235 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1236 	return 0;
1237 
1238 err_queues:
1239 	free_page((unsigned long) irq_ptr->qdr);
1240 err_qdr:
1241 	free_page(irq_ptr->chsc_page);
1242 err_chsc:
1243 err_dbf:
1244 	free_page((unsigned long) irq_ptr);
1245 	return rc;
1246 }
1247 EXPORT_SYMBOL_GPL(qdio_allocate);
1248 
1249 static void qdio_detect_hsicq(struct qdio_irq *irq_ptr)
1250 {
1251 	struct qdio_q *q = irq_ptr->input_qs[0];
1252 	int i, use_cq = 0;
1253 
1254 	if (irq_ptr->nr_input_qs > 1 && queue_type(q) == QDIO_IQDIO_QFMT)
1255 		use_cq = 1;
1256 
1257 	for_each_output_queue(irq_ptr, q, i) {
1258 		if (use_cq) {
1259 			if (multicast_outbound(q))
1260 				continue;
1261 			if (qdio_enable_async_operation(&q->u.out) < 0) {
1262 				use_cq = 0;
1263 				continue;
1264 			}
1265 		} else
1266 			qdio_disable_async_operation(&q->u.out);
1267 	}
1268 	DBF_EVENT("use_cq:%d", use_cq);
1269 }
1270 
1271 static void qdio_trace_init_data(struct qdio_irq *irq,
1272 				 struct qdio_initialize *data)
1273 {
1274 	DBF_DEV_EVENT(DBF_ERR, irq, "qfmt:%1u", data->q_format);
1275 	DBF_DEV_HEX(irq, data->adapter_name, 8, DBF_ERR);
1276 	DBF_DEV_EVENT(DBF_ERR, irq, "qpff%4x", data->qib_param_field_format);
1277 	DBF_DEV_HEX(irq, &data->qib_param_field, sizeof(void *), DBF_ERR);
1278 	DBF_DEV_HEX(irq, &data->input_slib_elements, sizeof(void *), DBF_ERR);
1279 	DBF_DEV_HEX(irq, &data->output_slib_elements, sizeof(void *), DBF_ERR);
1280 	DBF_DEV_EVENT(DBF_ERR, irq, "niq:%1u noq:%1u", data->no_input_qs,
1281 		      data->no_output_qs);
1282 	DBF_DEV_HEX(irq, &data->input_handler, sizeof(void *), DBF_ERR);
1283 	DBF_DEV_HEX(irq, &data->output_handler, sizeof(void *), DBF_ERR);
1284 	DBF_DEV_HEX(irq, &data->int_parm, sizeof(long), DBF_ERR);
1285 	DBF_DEV_HEX(irq, &data->input_sbal_addr_array, sizeof(void *), DBF_ERR);
1286 	DBF_DEV_HEX(irq, &data->output_sbal_addr_array, sizeof(void *),
1287 		    DBF_ERR);
1288 }
1289 
1290 /**
1291  * qdio_establish - establish queues on a qdio subchannel
1292  * @cdev: associated ccw device
1293  * @init_data: initialization data
1294  */
1295 int qdio_establish(struct ccw_device *cdev,
1296 		   struct qdio_initialize *init_data)
1297 {
1298 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1299 	struct subchannel_id schid;
1300 	int rc;
1301 
1302 	ccw_device_get_schid(cdev, &schid);
1303 	DBF_EVENT("qestablish:%4x", schid.sch_no);
1304 
1305 	if (!irq_ptr)
1306 		return -ENODEV;
1307 
1308 	if (init_data->no_input_qs > irq_ptr->max_input_qs ||
1309 	    init_data->no_output_qs > irq_ptr->max_output_qs)
1310 		return -EINVAL;
1311 
1312 	if ((init_data->no_input_qs && !init_data->input_handler) ||
1313 	    (init_data->no_output_qs && !init_data->output_handler))
1314 		return -EINVAL;
1315 
1316 	if (!init_data->input_sbal_addr_array ||
1317 	    !init_data->output_sbal_addr_array)
1318 		return -EINVAL;
1319 
1320 	mutex_lock(&irq_ptr->setup_mutex);
1321 	qdio_trace_init_data(irq_ptr, init_data);
1322 	qdio_setup_irq(irq_ptr, init_data);
1323 
1324 	rc = qdio_establish_thinint(irq_ptr);
1325 	if (rc) {
1326 		qdio_shutdown_irq(irq_ptr);
1327 		mutex_unlock(&irq_ptr->setup_mutex);
1328 		return rc;
1329 	}
1330 
1331 	/* establish q */
1332 	irq_ptr->ccw.cmd_code = irq_ptr->equeue.cmd;
1333 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1334 	irq_ptr->ccw.count = irq_ptr->equeue.count;
1335 	irq_ptr->ccw.cda = (u32)((addr_t)irq_ptr->qdr);
1336 
1337 	spin_lock_irq(get_ccwdev_lock(cdev));
1338 	ccw_device_set_options_mask(cdev, 0);
1339 
1340 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ESTABLISH, 0, 0);
1341 	spin_unlock_irq(get_ccwdev_lock(cdev));
1342 	if (rc) {
1343 		DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no);
1344 		DBF_ERROR("rc:%4x", rc);
1345 		qdio_shutdown_thinint(irq_ptr);
1346 		qdio_shutdown_irq(irq_ptr);
1347 		mutex_unlock(&irq_ptr->setup_mutex);
1348 		return rc;
1349 	}
1350 
1351 	wait_event_interruptible_timeout(cdev->private->wait_q,
1352 		irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
1353 		irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ);
1354 
1355 	if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) {
1356 		mutex_unlock(&irq_ptr->setup_mutex);
1357 		qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
1358 		return -EIO;
1359 	}
1360 
1361 	qdio_setup_ssqd_info(irq_ptr);
1362 
1363 	qdio_detect_hsicq(irq_ptr);
1364 
1365 	/* qebsm is now setup if available, initialize buffer states */
1366 	qdio_init_buf_states(irq_ptr);
1367 
1368 	mutex_unlock(&irq_ptr->setup_mutex);
1369 	qdio_print_subchannel_info(irq_ptr);
1370 	qdio_setup_debug_entries(irq_ptr);
1371 	return 0;
1372 }
1373 EXPORT_SYMBOL_GPL(qdio_establish);
1374 
1375 /**
1376  * qdio_activate - activate queues on a qdio subchannel
1377  * @cdev: associated cdev
1378  */
1379 int qdio_activate(struct ccw_device *cdev)
1380 {
1381 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1382 	struct subchannel_id schid;
1383 	int rc;
1384 
1385 	ccw_device_get_schid(cdev, &schid);
1386 	DBF_EVENT("qactivate:%4x", schid.sch_no);
1387 
1388 	if (!irq_ptr)
1389 		return -ENODEV;
1390 
1391 	mutex_lock(&irq_ptr->setup_mutex);
1392 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1393 		rc = -EBUSY;
1394 		goto out;
1395 	}
1396 
1397 	irq_ptr->ccw.cmd_code = irq_ptr->aqueue.cmd;
1398 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1399 	irq_ptr->ccw.count = irq_ptr->aqueue.count;
1400 	irq_ptr->ccw.cda = 0;
1401 
1402 	spin_lock_irq(get_ccwdev_lock(cdev));
1403 	ccw_device_set_options(cdev, CCWDEV_REPORT_ALL);
1404 
1405 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ACTIVATE,
1406 			      0, DOIO_DENY_PREFETCH);
1407 	spin_unlock_irq(get_ccwdev_lock(cdev));
1408 	if (rc) {
1409 		DBF_ERROR("%4x act IO ERR", irq_ptr->schid.sch_no);
1410 		DBF_ERROR("rc:%4x", rc);
1411 		goto out;
1412 	}
1413 
1414 	if (is_thinint_irq(irq_ptr))
1415 		tiqdio_add_device(irq_ptr);
1416 
1417 	/* wait for subchannel to become active */
1418 	msleep(5);
1419 
1420 	switch (irq_ptr->state) {
1421 	case QDIO_IRQ_STATE_STOPPED:
1422 	case QDIO_IRQ_STATE_ERR:
1423 		rc = -EIO;
1424 		break;
1425 	default:
1426 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ACTIVE);
1427 		rc = 0;
1428 	}
1429 out:
1430 	mutex_unlock(&irq_ptr->setup_mutex);
1431 	return rc;
1432 }
1433 EXPORT_SYMBOL_GPL(qdio_activate);
1434 
1435 /**
1436  * handle_inbound - reset processed input buffers
1437  * @q: queue containing the buffers
1438  * @callflags: flags
1439  * @bufnr: first buffer to process
1440  * @count: how many buffers are emptied
1441  */
1442 static int handle_inbound(struct qdio_q *q, unsigned int callflags,
1443 			  int bufnr, int count)
1444 {
1445 	int overlap;
1446 
1447 	qperf_inc(q, inbound_call);
1448 
1449 	/* If any ACKed SBALs are returned to HW, adjust ACK tracking: */
1450 	overlap = min(count - sub_buf(q->u.in.ack_start, bufnr),
1451 		      q->u.in.ack_count);
1452 	if (overlap > 0) {
1453 		q->u.in.ack_start = add_buf(q->u.in.ack_start, overlap);
1454 		q->u.in.ack_count -= overlap;
1455 	}
1456 
1457 	count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
1458 	atomic_add(count, &q->nr_buf_used);
1459 
1460 	if (need_siga_in(q))
1461 		return qdio_siga_input(q);
1462 
1463 	return 0;
1464 }
1465 
1466 /**
1467  * handle_outbound - process filled outbound buffers
1468  * @q: queue containing the buffers
1469  * @callflags: flags
1470  * @bufnr: first buffer to process
1471  * @count: how many buffers are filled
1472  */
1473 static int handle_outbound(struct qdio_q *q, unsigned int callflags,
1474 			   unsigned int bufnr, unsigned int count)
1475 {
1476 	const unsigned int scan_threshold = q->irq_ptr->scan_threshold;
1477 	unsigned char state = 0;
1478 	int used, rc = 0;
1479 
1480 	qperf_inc(q, outbound_call);
1481 
1482 	count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
1483 	used = atomic_add_return(count, &q->nr_buf_used);
1484 
1485 	if (used == QDIO_MAX_BUFFERS_PER_Q)
1486 		qperf_inc(q, outbound_queue_full);
1487 
1488 	if (callflags & QDIO_FLAG_PCI_OUT) {
1489 		q->u.out.pci_out_enabled = 1;
1490 		qperf_inc(q, pci_request_int);
1491 	} else
1492 		q->u.out.pci_out_enabled = 0;
1493 
1494 	if (queue_type(q) == QDIO_IQDIO_QFMT) {
1495 		unsigned long phys_aob = 0;
1496 
1497 		if (q->u.out.use_cq && count == 1)
1498 			phys_aob = qdio_aob_for_buffer(&q->u.out, bufnr);
1499 
1500 		rc = qdio_kick_outbound_q(q, count, phys_aob);
1501 	} else if (need_siga_sync(q)) {
1502 		rc = qdio_siga_sync_q(q);
1503 	} else if (count < QDIO_MAX_BUFFERS_PER_Q &&
1504 		   get_buf_state(q, prev_buf(bufnr), &state, 0) > 0 &&
1505 		   state == SLSB_CU_OUTPUT_PRIMED) {
1506 		/* The previous buffer is not processed yet, tack on. */
1507 		qperf_inc(q, fast_requeue);
1508 	} else {
1509 		rc = qdio_kick_outbound_q(q, count, 0);
1510 	}
1511 
1512 	/* Let drivers implement their own completion scanning: */
1513 	if (!scan_threshold)
1514 		return rc;
1515 
1516 	/* in case of SIGA errors we must process the error immediately */
1517 	if (used >= scan_threshold || rc)
1518 		qdio_tasklet_schedule(q);
1519 	else
1520 		/* free the SBALs in case of no further traffic */
1521 		if (!timer_pending(&q->u.out.timer) &&
1522 		    likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
1523 			mod_timer(&q->u.out.timer, jiffies + HZ);
1524 	return rc;
1525 }
1526 
1527 /**
1528  * do_QDIO - process input or output buffers
1529  * @cdev: associated ccw_device for the qdio subchannel
1530  * @callflags: input or output and special flags from the program
1531  * @q_nr: queue number
1532  * @bufnr: buffer number
1533  * @count: how many buffers to process
1534  */
1535 int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
1536 	    int q_nr, unsigned int bufnr, unsigned int count)
1537 {
1538 	struct qdio_irq *irq_ptr;
1539 
1540 	if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1541 		return -EINVAL;
1542 
1543 	irq_ptr = cdev->private->qdio_data;
1544 	if (!irq_ptr)
1545 		return -ENODEV;
1546 
1547 	DBF_DEV_EVENT(DBF_INFO, irq_ptr,
1548 		      "do%02x b:%02x c:%02x", callflags, bufnr, count);
1549 
1550 	if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1551 		return -EIO;
1552 	if (!count)
1553 		return 0;
1554 	if (callflags & QDIO_FLAG_SYNC_INPUT)
1555 		return handle_inbound(irq_ptr->input_qs[q_nr],
1556 				      callflags, bufnr, count);
1557 	else if (callflags & QDIO_FLAG_SYNC_OUTPUT)
1558 		return handle_outbound(irq_ptr->output_qs[q_nr],
1559 				       callflags, bufnr, count);
1560 	return -EINVAL;
1561 }
1562 EXPORT_SYMBOL_GPL(do_QDIO);
1563 
1564 /**
1565  * qdio_start_irq - enable interrupt processing for the device
1566  * @cdev: associated ccw_device for the qdio subchannel
1567  *
1568  * Return codes
1569  *   0 - success
1570  *   1 - irqs not started since new data is available
1571  */
1572 int qdio_start_irq(struct ccw_device *cdev)
1573 {
1574 	struct qdio_q *q;
1575 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1576 	unsigned int i;
1577 
1578 	if (!irq_ptr)
1579 		return -ENODEV;
1580 
1581 	for_each_input_queue(irq_ptr, q, i)
1582 		qdio_stop_polling(q);
1583 
1584 	clear_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state);
1585 
1586 	/*
1587 	 * We need to check again to not lose initiative after
1588 	 * resetting the ACK state.
1589 	 */
1590 	if (test_nonshared_ind(irq_ptr))
1591 		goto rescan;
1592 
1593 	for_each_input_queue(irq_ptr, q, i) {
1594 		if (!qdio_inbound_q_done(q, q->first_to_check))
1595 			goto rescan;
1596 	}
1597 
1598 	return 0;
1599 
1600 rescan:
1601 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1602 		return 0;
1603 	else
1604 		return 1;
1605 
1606 }
1607 EXPORT_SYMBOL(qdio_start_irq);
1608 
1609 static int __qdio_inspect_queue(struct qdio_q *q, unsigned int *bufnr,
1610 				unsigned int *error)
1611 {
1612 	unsigned int start = q->first_to_check;
1613 	int count;
1614 
1615 	count = q->is_input_q ? qdio_inbound_q_moved(q, start) :
1616 				qdio_outbound_q_moved(q, start);
1617 	if (count == 0)
1618 		return 0;
1619 
1620 	*bufnr = start;
1621 	*error = q->qdio_error;
1622 
1623 	/* for the next time */
1624 	q->first_to_check = add_buf(start, count);
1625 	q->qdio_error = 0;
1626 
1627 	return count;
1628 }
1629 
1630 int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, bool is_input,
1631 		       unsigned int *bufnr, unsigned int *error)
1632 {
1633 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1634 	struct qdio_q *q;
1635 
1636 	if (!irq_ptr)
1637 		return -ENODEV;
1638 	q = is_input ? irq_ptr->input_qs[nr] : irq_ptr->output_qs[nr];
1639 
1640 	if (need_siga_sync(q))
1641 		qdio_siga_sync_q(q);
1642 
1643 	return __qdio_inspect_queue(q, bufnr, error);
1644 }
1645 EXPORT_SYMBOL_GPL(qdio_inspect_queue);
1646 
1647 /**
1648  * qdio_get_next_buffers - process input buffers
1649  * @cdev: associated ccw_device for the qdio subchannel
1650  * @nr: input queue number
1651  * @bufnr: first filled buffer number
1652  * @error: buffers are in error state
1653  *
1654  * Return codes
1655  *   < 0 - error
1656  *   = 0 - no new buffers found
1657  *   > 0 - number of processed buffers
1658  */
1659 int qdio_get_next_buffers(struct ccw_device *cdev, int nr, int *bufnr,
1660 			  int *error)
1661 {
1662 	struct qdio_q *q;
1663 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1664 
1665 	if (!irq_ptr)
1666 		return -ENODEV;
1667 	q = irq_ptr->input_qs[nr];
1668 
1669 	/*
1670 	 * Cannot rely on automatic sync after interrupt since queues may
1671 	 * also be examined without interrupt.
1672 	 */
1673 	if (need_siga_sync(q))
1674 		qdio_sync_queues(q);
1675 
1676 	qdio_check_outbound_pci_queues(irq_ptr);
1677 
1678 	/* Note: upper-layer MUST stop processing immediately here ... */
1679 	if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
1680 		return -EIO;
1681 
1682 	return __qdio_inspect_queue(q, bufnr, error);
1683 }
1684 EXPORT_SYMBOL(qdio_get_next_buffers);
1685 
1686 /**
1687  * qdio_stop_irq - disable interrupt processing for the device
1688  * @cdev: associated ccw_device for the qdio subchannel
1689  *
1690  * Return codes
1691  *   0 - interrupts were already disabled
1692  *   1 - interrupts successfully disabled
1693  */
1694 int qdio_stop_irq(struct ccw_device *cdev)
1695 {
1696 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1697 
1698 	if (!irq_ptr)
1699 		return -ENODEV;
1700 
1701 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1702 		return 0;
1703 	else
1704 		return 1;
1705 }
1706 EXPORT_SYMBOL(qdio_stop_irq);
1707 
1708 static int __init init_QDIO(void)
1709 {
1710 	int rc;
1711 
1712 	rc = qdio_debug_init();
1713 	if (rc)
1714 		return rc;
1715 	rc = qdio_setup_init();
1716 	if (rc)
1717 		goto out_debug;
1718 	rc = qdio_thinint_init();
1719 	if (rc)
1720 		goto out_cache;
1721 	return 0;
1722 
1723 out_cache:
1724 	qdio_setup_exit();
1725 out_debug:
1726 	qdio_debug_exit();
1727 	return rc;
1728 }
1729 
1730 static void __exit exit_QDIO(void)
1731 {
1732 	qdio_thinint_exit();
1733 	qdio_setup_exit();
1734 	qdio_debug_exit();
1735 }
1736 
1737 module_init(init_QDIO);
1738 module_exit(exit_QDIO);
1739