xref: /openbmc/linux/drivers/s390/cio/qdio_main.c (revision 31e67366)
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)
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 	for (; i < count; i++) {
221 		bufnr = next_buf(bufnr);
222 
223 		/* stop if next state differs from initial state: */
224 		if (q->slsb.val[bufnr] != __state)
225 			break;
226 	}
227 
228 out:
229 	*state = __state;
230 	return i;
231 }
232 
233 static inline int get_buf_state(struct qdio_q *q, unsigned int bufnr,
234 				unsigned char *state, int auto_ack)
235 {
236 	return get_buf_states(q, bufnr, state, 1, auto_ack);
237 }
238 
239 /* wrap-around safe setting of slsb states, returns number of changed buffers */
240 static inline int set_buf_states(struct qdio_q *q, int bufnr,
241 				 unsigned char state, int count)
242 {
243 	int i;
244 
245 	if (is_qebsm(q))
246 		return qdio_do_sqbs(q, state, bufnr, count);
247 
248 	/* Ensure that all preceding changes to the SBALs are visible: */
249 	mb();
250 
251 	for (i = 0; i < count; i++) {
252 		WRITE_ONCE(q->slsb.val[bufnr], state);
253 		bufnr = next_buf(bufnr);
254 	}
255 
256 	/* Make our SLSB changes visible: */
257 	mb();
258 
259 	return count;
260 }
261 
262 static inline int set_buf_state(struct qdio_q *q, int bufnr,
263 				unsigned char state)
264 {
265 	return set_buf_states(q, bufnr, state, 1);
266 }
267 
268 /* set slsb states to initial state */
269 static void qdio_init_buf_states(struct qdio_irq *irq_ptr)
270 {
271 	struct qdio_q *q;
272 	int i;
273 
274 	for_each_input_queue(irq_ptr, q, i)
275 		set_buf_states(q, 0, SLSB_P_INPUT_NOT_INIT,
276 			       QDIO_MAX_BUFFERS_PER_Q);
277 	for_each_output_queue(irq_ptr, q, i)
278 		set_buf_states(q, 0, SLSB_P_OUTPUT_NOT_INIT,
279 			       QDIO_MAX_BUFFERS_PER_Q);
280 }
281 
282 static inline int qdio_siga_sync(struct qdio_q *q, unsigned int output,
283 			  unsigned int input)
284 {
285 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
286 	unsigned int fc = QDIO_SIGA_SYNC;
287 	int cc;
288 
289 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-s:%1d", q->nr);
290 	qperf_inc(q, siga_sync);
291 
292 	if (is_qebsm(q)) {
293 		schid = q->irq_ptr->sch_token;
294 		fc |= QDIO_SIGA_QEBSM_FLAG;
295 	}
296 
297 	cc = do_siga_sync(schid, output, input, fc);
298 	if (unlikely(cc))
299 		DBF_ERROR("%4x SIGA-S:%2d", SCH_NO(q), cc);
300 	return (cc) ? -EIO : 0;
301 }
302 
303 static inline int qdio_siga_sync_q(struct qdio_q *q)
304 {
305 	if (q->is_input_q)
306 		return qdio_siga_sync(q, 0, q->mask);
307 	else
308 		return qdio_siga_sync(q, q->mask, 0);
309 }
310 
311 static int qdio_siga_output(struct qdio_q *q, unsigned int count,
312 			    unsigned int *busy_bit, unsigned long aob)
313 {
314 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
315 	unsigned int fc = QDIO_SIGA_WRITE;
316 	u64 start_time = 0;
317 	int retries = 0, cc;
318 
319 	if (queue_type(q) == QDIO_IQDIO_QFMT && !multicast_outbound(q)) {
320 		if (count > 1)
321 			fc = QDIO_SIGA_WRITEM;
322 		else if (aob)
323 			fc = QDIO_SIGA_WRITEQ;
324 	}
325 
326 	if (is_qebsm(q)) {
327 		schid = q->irq_ptr->sch_token;
328 		fc |= QDIO_SIGA_QEBSM_FLAG;
329 	}
330 again:
331 	cc = do_siga_output(schid, q->mask, busy_bit, fc, aob);
332 
333 	/* hipersocket busy condition */
334 	if (unlikely(*busy_bit)) {
335 		retries++;
336 
337 		if (!start_time) {
338 			start_time = get_tod_clock_fast();
339 			goto again;
340 		}
341 		if (get_tod_clock_fast() - start_time < QDIO_BUSY_BIT_PATIENCE)
342 			goto again;
343 	}
344 	if (retries) {
345 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr,
346 			      "%4x cc2 BB1:%1d", SCH_NO(q), q->nr);
347 		DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "count:%u", retries);
348 	}
349 	return cc;
350 }
351 
352 static inline int qdio_siga_input(struct qdio_q *q)
353 {
354 	unsigned long schid = *((u32 *) &q->irq_ptr->schid);
355 	unsigned int fc = QDIO_SIGA_READ;
356 	int cc;
357 
358 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-r:%1d", q->nr);
359 	qperf_inc(q, siga_read);
360 
361 	if (is_qebsm(q)) {
362 		schid = q->irq_ptr->sch_token;
363 		fc |= QDIO_SIGA_QEBSM_FLAG;
364 	}
365 
366 	cc = do_siga_input(schid, q->mask, fc);
367 	if (unlikely(cc))
368 		DBF_ERROR("%4x SIGA-R:%2d", SCH_NO(q), cc);
369 	return (cc) ? -EIO : 0;
370 }
371 
372 #define qdio_siga_sync_out(q) qdio_siga_sync(q, ~0U, 0)
373 #define qdio_siga_sync_all(q) qdio_siga_sync(q, ~0U, ~0U)
374 
375 static inline void qdio_sync_queues(struct qdio_q *q)
376 {
377 	/* PCI capable outbound queues will also be scanned so sync them too */
378 	if (pci_out_supported(q->irq_ptr))
379 		qdio_siga_sync_all(q);
380 	else
381 		qdio_siga_sync_q(q);
382 }
383 
384 int debug_get_buf_state(struct qdio_q *q, unsigned int bufnr,
385 			unsigned char *state)
386 {
387 	if (need_siga_sync(q))
388 		qdio_siga_sync_q(q);
389 	return get_buf_state(q, bufnr, state, 0);
390 }
391 
392 static inline void qdio_stop_polling(struct qdio_q *q)
393 {
394 	if (!q->u.in.batch_count)
395 		return;
396 
397 	qperf_inc(q, stop_polling);
398 
399 	/* show the card that we are not polling anymore */
400 	set_buf_states(q, q->u.in.batch_start, SLSB_P_INPUT_NOT_INIT,
401 		       q->u.in.batch_count);
402 	q->u.in.batch_count = 0;
403 }
404 
405 static inline void account_sbals(struct qdio_q *q, unsigned int count)
406 {
407 	q->q_stats.nr_sbal_total += count;
408 	q->q_stats.nr_sbals[ilog2(count)]++;
409 }
410 
411 static void process_buffer_error(struct qdio_q *q, unsigned int start,
412 				 int count)
413 {
414 	/* special handling for no target buffer empty */
415 	if (queue_type(q) == QDIO_IQDIO_QFMT && !q->is_input_q &&
416 	    q->sbal[start]->element[15].sflags == 0x10) {
417 		qperf_inc(q, target_full);
418 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "OUTFULL FTC:%02x", start);
419 		return;
420 	}
421 
422 	DBF_ERROR("%4x BUF ERROR", SCH_NO(q));
423 	DBF_ERROR((q->is_input_q) ? "IN:%2d" : "OUT:%2d", q->nr);
424 	DBF_ERROR("FTC:%3d C:%3d", start, count);
425 	DBF_ERROR("F14:%2x F15:%2x",
426 		  q->sbal[start]->element[14].sflags,
427 		  q->sbal[start]->element[15].sflags);
428 }
429 
430 static inline void inbound_handle_work(struct qdio_q *q, unsigned int start,
431 				       int count, bool auto_ack)
432 {
433 	/* ACK the newest SBAL: */
434 	if (!auto_ack)
435 		set_buf_state(q, add_buf(start, count - 1), SLSB_P_INPUT_ACK);
436 
437 	if (!q->u.in.batch_count)
438 		q->u.in.batch_start = start;
439 	q->u.in.batch_count += count;
440 }
441 
442 static int get_inbound_buffer_frontier(struct qdio_q *q, unsigned int start,
443 				       unsigned int *error)
444 {
445 	unsigned char state = 0;
446 	int count;
447 
448 	q->timestamp = get_tod_clock_fast();
449 
450 	count = atomic_read(&q->nr_buf_used);
451 	if (!count)
452 		return 0;
453 
454 	/*
455 	 * No siga sync here, as a PCI or we after a thin interrupt
456 	 * already sync'ed the queues.
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 (need_siga_sync(q))
510 		qdio_siga_sync_q(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 inline unsigned long qdio_aob_for_buffer(struct qdio_output_q *q,
521 					int bufnr)
522 {
523 	unsigned long phys_aob = 0;
524 
525 	if (!q->aobs[bufnr]) {
526 		struct qaob *aob = qdio_allocate_aob();
527 		q->aobs[bufnr] = aob;
528 	}
529 	if (q->aobs[bufnr]) {
530 		q->aobs[bufnr]->user1 = (u64) q->sbal_state[bufnr].user;
531 		phys_aob = virt_to_phys(q->aobs[bufnr]);
532 		WARN_ON_ONCE(phys_aob & 0xFF);
533 	}
534 
535 	return phys_aob;
536 }
537 
538 static inline int qdio_tasklet_schedule(struct qdio_q *q)
539 {
540 	if (likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE)) {
541 		tasklet_schedule(&q->u.out.tasklet);
542 		return 0;
543 	}
544 	return -EPERM;
545 }
546 
547 static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start,
548 					unsigned int *error)
549 {
550 	unsigned char state = 0;
551 	unsigned int i;
552 	int count;
553 
554 	q->timestamp = get_tod_clock_fast();
555 
556 	if (need_siga_sync(q))
557 		if (((queue_type(q) != QDIO_IQDIO_QFMT) &&
558 		    !pci_out_supported(q->irq_ptr)) ||
559 		    (queue_type(q) == QDIO_IQDIO_QFMT &&
560 		    multicast_outbound(q)))
561 			qdio_siga_sync_q(q);
562 
563 	count = atomic_read(&q->nr_buf_used);
564 	if (!count)
565 		return 0;
566 
567 	count = get_buf_states(q, start, &state, count, 0);
568 	if (!count)
569 		return 0;
570 
571 	switch (state) {
572 	case SLSB_P_OUTPUT_PENDING:
573 		/* detach the utilized QAOBs: */
574 		for (i = 0; i < count; i++)
575 			q->u.out.aobs[QDIO_BUFNR(start + i)] = NULL;
576 
577 		*error = QDIO_ERROR_SLSB_PENDING;
578 		fallthrough;
579 	case SLSB_P_OUTPUT_EMPTY:
580 		/* the adapter got it */
581 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
582 			"out empty:%1d %02x", q->nr, count);
583 
584 		atomic_sub(count, &q->nr_buf_used);
585 		if (q->irq_ptr->perf_stat_enabled)
586 			account_sbals(q, count);
587 		return count;
588 	case SLSB_P_OUTPUT_ERROR:
589 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out error:%1d %02x",
590 			      q->nr, count);
591 
592 		*error = QDIO_ERROR_SLSB_STATE;
593 		process_buffer_error(q, start, count);
594 		atomic_sub(count, &q->nr_buf_used);
595 		if (q->irq_ptr->perf_stat_enabled)
596 			account_sbals_error(q, count);
597 		return count;
598 	case SLSB_CU_OUTPUT_PRIMED:
599 		/* the adapter has not fetched the output yet */
600 		if (q->irq_ptr->perf_stat_enabled)
601 			q->q_stats.nr_sbal_nop++;
602 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out primed:%1d",
603 			      q->nr);
604 		return 0;
605 	case SLSB_P_OUTPUT_HALTED:
606 		return 0;
607 	case SLSB_P_OUTPUT_NOT_INIT:
608 		/* We should never see this state, throw a WARN: */
609 	default:
610 		dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
611 			      "found state %#x at index %u on queue %u\n",
612 			      state, start, q->nr);
613 		return 0;
614 	}
615 }
616 
617 /* all buffers processed? */
618 static inline int qdio_outbound_q_done(struct qdio_q *q)
619 {
620 	return atomic_read(&q->nr_buf_used) == 0;
621 }
622 
623 static int qdio_kick_outbound_q(struct qdio_q *q, unsigned int count,
624 				unsigned long aob)
625 {
626 	int retries = 0, cc;
627 	unsigned int busy_bit;
628 
629 	if (!need_siga_out(q))
630 		return 0;
631 
632 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w:%1d", q->nr);
633 retry:
634 	qperf_inc(q, siga_write);
635 
636 	cc = qdio_siga_output(q, count, &busy_bit, aob);
637 	switch (cc) {
638 	case 0:
639 		break;
640 	case 2:
641 		if (busy_bit) {
642 			while (++retries < QDIO_BUSY_BIT_RETRIES) {
643 				mdelay(QDIO_BUSY_BIT_RETRY_DELAY);
644 				goto retry;
645 			}
646 			DBF_ERROR("%4x cc2 BBC:%1d", SCH_NO(q), q->nr);
647 			cc = -EBUSY;
648 		} else {
649 			DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w cc2:%1d", q->nr);
650 			cc = -ENOBUFS;
651 		}
652 		break;
653 	case 1:
654 	case 3:
655 		DBF_ERROR("%4x SIGA-W:%1d", SCH_NO(q), cc);
656 		cc = -EIO;
657 		break;
658 	}
659 	if (retries) {
660 		DBF_ERROR("%4x cc2 BB2:%1d", SCH_NO(q), q->nr);
661 		DBF_ERROR("count:%u", retries);
662 	}
663 	return cc;
664 }
665 
666 void qdio_outbound_tasklet(struct tasklet_struct *t)
667 {
668 	struct qdio_output_q *out_q = from_tasklet(out_q, t, tasklet);
669 	struct qdio_q *q = container_of(out_q, struct qdio_q, u.out);
670 	unsigned int start = q->first_to_check;
671 	unsigned int error = 0;
672 	int count;
673 
674 	qperf_inc(q, tasklet_outbound);
675 	WARN_ON_ONCE(atomic_read(&q->nr_buf_used) < 0);
676 
677 	count = get_outbound_buffer_frontier(q, start, &error);
678 	if (count) {
679 		q->first_to_check = add_buf(start, count);
680 
681 		if (q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE) {
682 			qperf_inc(q, outbound_handler);
683 			DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "koh: s:%02x c:%02x",
684 				      start, count);
685 
686 			q->handler(q->irq_ptr->cdev, error, q->nr, start,
687 				   count, q->irq_ptr->int_parm);
688 		}
689 	}
690 
691 	if (queue_type(q) == QDIO_ZFCP_QFMT && !pci_out_supported(q->irq_ptr) &&
692 	    !qdio_outbound_q_done(q))
693 		goto sched;
694 
695 	if (q->u.out.pci_out_enabled)
696 		return;
697 
698 	/*
699 	 * Now we know that queue type is either qeth without pci enabled
700 	 * or HiperSockets. Make sure buffer switch from PRIMED to EMPTY
701 	 * is noticed and outbound_handler is called after some time.
702 	 */
703 	if (qdio_outbound_q_done(q))
704 		del_timer_sync(&q->u.out.timer);
705 	else
706 		if (!timer_pending(&q->u.out.timer) &&
707 		    likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
708 			mod_timer(&q->u.out.timer, jiffies + 10 * HZ);
709 	return;
710 
711 sched:
712 	qdio_tasklet_schedule(q);
713 }
714 
715 void qdio_outbound_timer(struct timer_list *t)
716 {
717 	struct qdio_q *q = from_timer(q, t, u.out.timer);
718 
719 	qdio_tasklet_schedule(q);
720 }
721 
722 static inline void qdio_check_outbound_pci_queues(struct qdio_irq *irq)
723 {
724 	struct qdio_q *out;
725 	int i;
726 
727 	if (!pci_out_supported(irq) || !irq->scan_threshold)
728 		return;
729 
730 	for_each_output_queue(irq, out, i)
731 		if (!qdio_outbound_q_done(out))
732 			qdio_tasklet_schedule(out);
733 }
734 
735 static inline void qdio_set_state(struct qdio_irq *irq_ptr,
736 				  enum qdio_irq_states state)
737 {
738 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "newstate: %1d", state);
739 
740 	irq_ptr->state = state;
741 	mb();
742 }
743 
744 static void qdio_irq_check_sense(struct qdio_irq *irq_ptr, struct irb *irb)
745 {
746 	if (irb->esw.esw0.erw.cons) {
747 		DBF_ERROR("%4x sense:", irq_ptr->schid.sch_no);
748 		DBF_ERROR_HEX(irb, 64);
749 		DBF_ERROR_HEX(irb->ecw, 64);
750 	}
751 }
752 
753 /* PCI interrupt handler */
754 static void qdio_int_handler_pci(struct qdio_irq *irq_ptr)
755 {
756 	int i;
757 	struct qdio_q *q;
758 
759 	if (unlikely(irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
760 		return;
761 
762 	qdio_deliver_irq(irq_ptr);
763 	irq_ptr->last_data_irq_time = S390_lowcore.int_clock;
764 
765 	if (!pci_out_supported(irq_ptr) || !irq_ptr->scan_threshold)
766 		return;
767 
768 	for_each_output_queue(irq_ptr, q, i) {
769 		if (qdio_outbound_q_done(q))
770 			continue;
771 		if (need_siga_sync(q) && need_siga_sync_out_after_pci(q))
772 			qdio_siga_sync_q(q);
773 		qdio_tasklet_schedule(q);
774 	}
775 }
776 
777 static void qdio_handle_activate_check(struct qdio_irq *irq_ptr,
778 				       unsigned long intparm, int cstat,
779 				       int dstat)
780 {
781 	struct qdio_q *q;
782 
783 	DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
784 	DBF_ERROR("intp :%lx", intparm);
785 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
786 
787 	if (irq_ptr->nr_input_qs) {
788 		q = irq_ptr->input_qs[0];
789 	} else if (irq_ptr->nr_output_qs) {
790 		q = irq_ptr->output_qs[0];
791 	} else {
792 		dump_stack();
793 		goto no_handler;
794 	}
795 
796 	q->handler(q->irq_ptr->cdev, QDIO_ERROR_ACTIVATE,
797 		   q->nr, q->first_to_check, 0, irq_ptr->int_parm);
798 no_handler:
799 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
800 	/*
801 	 * In case of z/VM LGR (Live Guest Migration) QDIO recovery will happen.
802 	 * Therefore we call the LGR detection function here.
803 	 */
804 	lgr_info_log();
805 }
806 
807 static void qdio_establish_handle_irq(struct qdio_irq *irq_ptr, int cstat,
808 				      int dstat)
809 {
810 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qest irq");
811 
812 	if (cstat)
813 		goto error;
814 	if (dstat & ~(DEV_STAT_DEV_END | DEV_STAT_CHN_END))
815 		goto error;
816 	if (!(dstat & DEV_STAT_DEV_END))
817 		goto error;
818 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ESTABLISHED);
819 	return;
820 
821 error:
822 	DBF_ERROR("%4x EQ:error", irq_ptr->schid.sch_no);
823 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
824 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
825 }
826 
827 /* qdio interrupt handler */
828 void qdio_int_handler(struct ccw_device *cdev, unsigned long intparm,
829 		      struct irb *irb)
830 {
831 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
832 	struct subchannel_id schid;
833 	int cstat, dstat;
834 
835 	if (!intparm || !irq_ptr) {
836 		ccw_device_get_schid(cdev, &schid);
837 		DBF_ERROR("qint:%4x", schid.sch_no);
838 		return;
839 	}
840 
841 	if (irq_ptr->perf_stat_enabled)
842 		irq_ptr->perf_stat.qdio_int++;
843 
844 	if (IS_ERR(irb)) {
845 		DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
846 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
847 		wake_up(&cdev->private->wait_q);
848 		return;
849 	}
850 	qdio_irq_check_sense(irq_ptr, irb);
851 	cstat = irb->scsw.cmd.cstat;
852 	dstat = irb->scsw.cmd.dstat;
853 
854 	switch (irq_ptr->state) {
855 	case QDIO_IRQ_STATE_INACTIVE:
856 		qdio_establish_handle_irq(irq_ptr, cstat, dstat);
857 		break;
858 	case QDIO_IRQ_STATE_CLEANUP:
859 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
860 		break;
861 	case QDIO_IRQ_STATE_ESTABLISHED:
862 	case QDIO_IRQ_STATE_ACTIVE:
863 		if (cstat & SCHN_STAT_PCI) {
864 			qdio_int_handler_pci(irq_ptr);
865 			return;
866 		}
867 		if (cstat || dstat)
868 			qdio_handle_activate_check(irq_ptr, intparm, cstat,
869 						   dstat);
870 		break;
871 	case QDIO_IRQ_STATE_STOPPED:
872 		break;
873 	default:
874 		WARN_ON_ONCE(1);
875 	}
876 	wake_up(&cdev->private->wait_q);
877 }
878 
879 /**
880  * qdio_get_ssqd_desc - get qdio subchannel description
881  * @cdev: ccw device to get description for
882  * @data: where to store the ssqd
883  *
884  * Returns 0 or an error code. The results of the chsc are stored in the
885  * specified structure.
886  */
887 int qdio_get_ssqd_desc(struct ccw_device *cdev,
888 		       struct qdio_ssqd_desc *data)
889 {
890 	struct subchannel_id schid;
891 
892 	if (!cdev || !cdev->private)
893 		return -EINVAL;
894 
895 	ccw_device_get_schid(cdev, &schid);
896 	DBF_EVENT("get ssqd:%4x", schid.sch_no);
897 	return qdio_setup_get_ssqd(NULL, &schid, data);
898 }
899 EXPORT_SYMBOL_GPL(qdio_get_ssqd_desc);
900 
901 static void qdio_shutdown_queues(struct qdio_irq *irq_ptr)
902 {
903 	struct qdio_q *q;
904 	int i;
905 
906 	for_each_output_queue(irq_ptr, q, i) {
907 		del_timer_sync(&q->u.out.timer);
908 		tasklet_kill(&q->u.out.tasklet);
909 	}
910 }
911 
912 /**
913  * qdio_shutdown - shut down a qdio subchannel
914  * @cdev: associated ccw device
915  * @how: use halt or clear to shutdown
916  */
917 int qdio_shutdown(struct ccw_device *cdev, int how)
918 {
919 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
920 	struct subchannel_id schid;
921 	int rc;
922 
923 	if (!irq_ptr)
924 		return -ENODEV;
925 
926 	WARN_ON_ONCE(irqs_disabled());
927 	ccw_device_get_schid(cdev, &schid);
928 	DBF_EVENT("qshutdown:%4x", schid.sch_no);
929 
930 	mutex_lock(&irq_ptr->setup_mutex);
931 	/*
932 	 * Subchannel was already shot down. We cannot prevent being called
933 	 * twice since cio may trigger a shutdown asynchronously.
934 	 */
935 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
936 		mutex_unlock(&irq_ptr->setup_mutex);
937 		return 0;
938 	}
939 
940 	/*
941 	 * Indicate that the device is going down. Scheduling the queue
942 	 * tasklets is forbidden from here on.
943 	 */
944 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
945 
946 	qdio_shutdown_queues(irq_ptr);
947 	qdio_shutdown_debug_entries(irq_ptr);
948 
949 	/* cleanup subchannel */
950 	spin_lock_irq(get_ccwdev_lock(cdev));
951 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_CLEANUP);
952 	if (how & QDIO_FLAG_CLEANUP_USING_CLEAR)
953 		rc = ccw_device_clear(cdev, QDIO_DOING_CLEANUP);
954 	else
955 		/* default behaviour is halt */
956 		rc = ccw_device_halt(cdev, QDIO_DOING_CLEANUP);
957 	spin_unlock_irq(get_ccwdev_lock(cdev));
958 	if (rc) {
959 		DBF_ERROR("%4x SHUTD ERR", irq_ptr->schid.sch_no);
960 		DBF_ERROR("rc:%4d", rc);
961 		goto no_cleanup;
962 	}
963 
964 	wait_event_interruptible_timeout(cdev->private->wait_q,
965 		irq_ptr->state == QDIO_IRQ_STATE_INACTIVE ||
966 		irq_ptr->state == QDIO_IRQ_STATE_ERR,
967 		10 * HZ);
968 
969 no_cleanup:
970 	qdio_shutdown_thinint(irq_ptr);
971 	qdio_shutdown_irq(irq_ptr);
972 
973 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
974 	mutex_unlock(&irq_ptr->setup_mutex);
975 	if (rc)
976 		return rc;
977 	return 0;
978 }
979 EXPORT_SYMBOL_GPL(qdio_shutdown);
980 
981 /**
982  * qdio_free - free data structures for a qdio subchannel
983  * @cdev: associated ccw device
984  */
985 int qdio_free(struct ccw_device *cdev)
986 {
987 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
988 	struct subchannel_id schid;
989 
990 	if (!irq_ptr)
991 		return -ENODEV;
992 
993 	ccw_device_get_schid(cdev, &schid);
994 	DBF_EVENT("qfree:%4x", schid.sch_no);
995 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf abandoned");
996 	mutex_lock(&irq_ptr->setup_mutex);
997 
998 	irq_ptr->debug_area = NULL;
999 	cdev->private->qdio_data = NULL;
1000 	mutex_unlock(&irq_ptr->setup_mutex);
1001 
1002 	qdio_free_async_data(irq_ptr);
1003 	qdio_free_queues(irq_ptr);
1004 	free_page((unsigned long) irq_ptr->qdr);
1005 	free_page(irq_ptr->chsc_page);
1006 	free_page((unsigned long) irq_ptr);
1007 	return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(qdio_free);
1010 
1011 /**
1012  * qdio_allocate - allocate qdio queues and associated data
1013  * @cdev: associated ccw device
1014  * @no_input_qs: allocate this number of Input Queues
1015  * @no_output_qs: allocate this number of Output Queues
1016  */
1017 int qdio_allocate(struct ccw_device *cdev, unsigned int no_input_qs,
1018 		  unsigned int no_output_qs)
1019 {
1020 	struct subchannel_id schid;
1021 	struct qdio_irq *irq_ptr;
1022 	int rc = -ENOMEM;
1023 
1024 	ccw_device_get_schid(cdev, &schid);
1025 	DBF_EVENT("qallocate:%4x", schid.sch_no);
1026 
1027 	if (no_input_qs > QDIO_MAX_QUEUES_PER_IRQ ||
1028 	    no_output_qs > QDIO_MAX_QUEUES_PER_IRQ)
1029 		return -EINVAL;
1030 
1031 	/* irq_ptr must be in GFP_DMA since it contains ccw1.cda */
1032 	irq_ptr = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1033 	if (!irq_ptr)
1034 		return -ENOMEM;
1035 
1036 	irq_ptr->cdev = cdev;
1037 	mutex_init(&irq_ptr->setup_mutex);
1038 	if (qdio_allocate_dbf(irq_ptr))
1039 		goto err_dbf;
1040 
1041 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "alloc niq:%1u noq:%1u", no_input_qs,
1042 		      no_output_qs);
1043 
1044 	/*
1045 	 * Allocate a page for the chsc calls in qdio_establish.
1046 	 * Must be pre-allocated since a zfcp recovery will call
1047 	 * qdio_establish. In case of low memory and swap on a zfcp disk
1048 	 * we may not be able to allocate memory otherwise.
1049 	 */
1050 	irq_ptr->chsc_page = get_zeroed_page(GFP_KERNEL);
1051 	if (!irq_ptr->chsc_page)
1052 		goto err_chsc;
1053 
1054 	/* qdr is used in ccw1.cda which is u32 */
1055 	irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1056 	if (!irq_ptr->qdr)
1057 		goto err_qdr;
1058 
1059 	rc = qdio_allocate_qs(irq_ptr, no_input_qs, no_output_qs);
1060 	if (rc)
1061 		goto err_queues;
1062 
1063 	cdev->private->qdio_data = irq_ptr;
1064 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1065 	return 0;
1066 
1067 err_queues:
1068 	free_page((unsigned long) irq_ptr->qdr);
1069 err_qdr:
1070 	free_page(irq_ptr->chsc_page);
1071 err_chsc:
1072 err_dbf:
1073 	free_page((unsigned long) irq_ptr);
1074 	return rc;
1075 }
1076 EXPORT_SYMBOL_GPL(qdio_allocate);
1077 
1078 static void qdio_detect_hsicq(struct qdio_irq *irq_ptr)
1079 {
1080 	struct qdio_q *q = irq_ptr->input_qs[0];
1081 	int i, use_cq = 0;
1082 
1083 	if (irq_ptr->nr_input_qs > 1 && queue_type(q) == QDIO_IQDIO_QFMT)
1084 		use_cq = 1;
1085 
1086 	for_each_output_queue(irq_ptr, q, i) {
1087 		if (use_cq) {
1088 			if (multicast_outbound(q))
1089 				continue;
1090 			if (qdio_enable_async_operation(&q->u.out) < 0) {
1091 				use_cq = 0;
1092 				continue;
1093 			}
1094 		} else
1095 			qdio_disable_async_operation(&q->u.out);
1096 	}
1097 	DBF_EVENT("use_cq:%d", use_cq);
1098 }
1099 
1100 static void qdio_trace_init_data(struct qdio_irq *irq,
1101 				 struct qdio_initialize *data)
1102 {
1103 	DBF_DEV_EVENT(DBF_ERR, irq, "qfmt:%1u", data->q_format);
1104 	DBF_DEV_EVENT(DBF_ERR, irq, "qpff%4x", data->qib_param_field_format);
1105 	DBF_DEV_HEX(irq, &data->qib_param_field, sizeof(void *), DBF_ERR);
1106 	DBF_DEV_HEX(irq, &data->input_slib_elements, sizeof(void *), DBF_ERR);
1107 	DBF_DEV_HEX(irq, &data->output_slib_elements, sizeof(void *), DBF_ERR);
1108 	DBF_DEV_EVENT(DBF_ERR, irq, "niq:%1u noq:%1u", data->no_input_qs,
1109 		      data->no_output_qs);
1110 	DBF_DEV_HEX(irq, &data->input_handler, sizeof(void *), DBF_ERR);
1111 	DBF_DEV_HEX(irq, &data->output_handler, sizeof(void *), DBF_ERR);
1112 	DBF_DEV_HEX(irq, &data->int_parm, sizeof(long), DBF_ERR);
1113 	DBF_DEV_HEX(irq, &data->input_sbal_addr_array, sizeof(void *), DBF_ERR);
1114 	DBF_DEV_HEX(irq, &data->output_sbal_addr_array, sizeof(void *),
1115 		    DBF_ERR);
1116 }
1117 
1118 /**
1119  * qdio_establish - establish queues on a qdio subchannel
1120  * @cdev: associated ccw device
1121  * @init_data: initialization data
1122  */
1123 int qdio_establish(struct ccw_device *cdev,
1124 		   struct qdio_initialize *init_data)
1125 {
1126 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1127 	struct subchannel_id schid;
1128 	int rc;
1129 
1130 	ccw_device_get_schid(cdev, &schid);
1131 	DBF_EVENT("qestablish:%4x", schid.sch_no);
1132 
1133 	if (!irq_ptr)
1134 		return -ENODEV;
1135 
1136 	if (init_data->no_input_qs > irq_ptr->max_input_qs ||
1137 	    init_data->no_output_qs > irq_ptr->max_output_qs)
1138 		return -EINVAL;
1139 
1140 	if ((init_data->no_input_qs && !init_data->input_handler) ||
1141 	    (init_data->no_output_qs && !init_data->output_handler))
1142 		return -EINVAL;
1143 
1144 	if (!init_data->input_sbal_addr_array ||
1145 	    !init_data->output_sbal_addr_array)
1146 		return -EINVAL;
1147 
1148 	if (!init_data->irq_poll)
1149 		return -EINVAL;
1150 
1151 	mutex_lock(&irq_ptr->setup_mutex);
1152 	qdio_trace_init_data(irq_ptr, init_data);
1153 	qdio_setup_irq(irq_ptr, init_data);
1154 
1155 	rc = qdio_establish_thinint(irq_ptr);
1156 	if (rc) {
1157 		qdio_shutdown_irq(irq_ptr);
1158 		mutex_unlock(&irq_ptr->setup_mutex);
1159 		return rc;
1160 	}
1161 
1162 	/* establish q */
1163 	irq_ptr->ccw.cmd_code = irq_ptr->equeue.cmd;
1164 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1165 	irq_ptr->ccw.count = irq_ptr->equeue.count;
1166 	irq_ptr->ccw.cda = (u32)((addr_t)irq_ptr->qdr);
1167 
1168 	spin_lock_irq(get_ccwdev_lock(cdev));
1169 	ccw_device_set_options_mask(cdev, 0);
1170 
1171 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ESTABLISH, 0, 0);
1172 	spin_unlock_irq(get_ccwdev_lock(cdev));
1173 	if (rc) {
1174 		DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no);
1175 		DBF_ERROR("rc:%4x", rc);
1176 		qdio_shutdown_thinint(irq_ptr);
1177 		qdio_shutdown_irq(irq_ptr);
1178 		mutex_unlock(&irq_ptr->setup_mutex);
1179 		return rc;
1180 	}
1181 
1182 	wait_event_interruptible_timeout(cdev->private->wait_q,
1183 		irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
1184 		irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ);
1185 
1186 	if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) {
1187 		mutex_unlock(&irq_ptr->setup_mutex);
1188 		qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
1189 		return -EIO;
1190 	}
1191 
1192 	qdio_setup_ssqd_info(irq_ptr);
1193 
1194 	qdio_detect_hsicq(irq_ptr);
1195 
1196 	/* qebsm is now setup if available, initialize buffer states */
1197 	qdio_init_buf_states(irq_ptr);
1198 
1199 	mutex_unlock(&irq_ptr->setup_mutex);
1200 	qdio_print_subchannel_info(irq_ptr);
1201 	qdio_setup_debug_entries(irq_ptr);
1202 	return 0;
1203 }
1204 EXPORT_SYMBOL_GPL(qdio_establish);
1205 
1206 /**
1207  * qdio_activate - activate queues on a qdio subchannel
1208  * @cdev: associated cdev
1209  */
1210 int qdio_activate(struct ccw_device *cdev)
1211 {
1212 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1213 	struct subchannel_id schid;
1214 	int rc;
1215 
1216 	ccw_device_get_schid(cdev, &schid);
1217 	DBF_EVENT("qactivate:%4x", schid.sch_no);
1218 
1219 	if (!irq_ptr)
1220 		return -ENODEV;
1221 
1222 	mutex_lock(&irq_ptr->setup_mutex);
1223 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1224 		rc = -EBUSY;
1225 		goto out;
1226 	}
1227 
1228 	irq_ptr->ccw.cmd_code = irq_ptr->aqueue.cmd;
1229 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1230 	irq_ptr->ccw.count = irq_ptr->aqueue.count;
1231 	irq_ptr->ccw.cda = 0;
1232 
1233 	spin_lock_irq(get_ccwdev_lock(cdev));
1234 	ccw_device_set_options(cdev, CCWDEV_REPORT_ALL);
1235 
1236 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ACTIVATE,
1237 			      0, DOIO_DENY_PREFETCH);
1238 	spin_unlock_irq(get_ccwdev_lock(cdev));
1239 	if (rc) {
1240 		DBF_ERROR("%4x act IO ERR", irq_ptr->schid.sch_no);
1241 		DBF_ERROR("rc:%4x", rc);
1242 		goto out;
1243 	}
1244 
1245 	/* wait for subchannel to become active */
1246 	msleep(5);
1247 
1248 	switch (irq_ptr->state) {
1249 	case QDIO_IRQ_STATE_STOPPED:
1250 	case QDIO_IRQ_STATE_ERR:
1251 		rc = -EIO;
1252 		break;
1253 	default:
1254 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ACTIVE);
1255 		rc = 0;
1256 	}
1257 out:
1258 	mutex_unlock(&irq_ptr->setup_mutex);
1259 	return rc;
1260 }
1261 EXPORT_SYMBOL_GPL(qdio_activate);
1262 
1263 /**
1264  * handle_inbound - reset processed input buffers
1265  * @q: queue containing the buffers
1266  * @callflags: flags
1267  * @bufnr: first buffer to process
1268  * @count: how many buffers are emptied
1269  */
1270 static int handle_inbound(struct qdio_q *q, unsigned int callflags,
1271 			  int bufnr, int count)
1272 {
1273 	int overlap;
1274 
1275 	qperf_inc(q, inbound_call);
1276 
1277 	/* If any processed SBALs are returned to HW, adjust our tracking: */
1278 	overlap = min_t(int, count - sub_buf(q->u.in.batch_start, bufnr),
1279 			     q->u.in.batch_count);
1280 	if (overlap > 0) {
1281 		q->u.in.batch_start = add_buf(q->u.in.batch_start, overlap);
1282 		q->u.in.batch_count -= overlap;
1283 	}
1284 
1285 	count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
1286 	atomic_add(count, &q->nr_buf_used);
1287 
1288 	if (need_siga_in(q))
1289 		return qdio_siga_input(q);
1290 
1291 	return 0;
1292 }
1293 
1294 /**
1295  * handle_outbound - process filled outbound buffers
1296  * @q: queue containing the buffers
1297  * @callflags: flags
1298  * @bufnr: first buffer to process
1299  * @count: how many buffers are filled
1300  */
1301 static int handle_outbound(struct qdio_q *q, unsigned int callflags,
1302 			   unsigned int bufnr, unsigned int count)
1303 {
1304 	const unsigned int scan_threshold = q->irq_ptr->scan_threshold;
1305 	unsigned char state = 0;
1306 	int used, rc = 0;
1307 
1308 	qperf_inc(q, outbound_call);
1309 
1310 	count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
1311 	used = atomic_add_return(count, &q->nr_buf_used);
1312 
1313 	if (used == QDIO_MAX_BUFFERS_PER_Q)
1314 		qperf_inc(q, outbound_queue_full);
1315 
1316 	if (callflags & QDIO_FLAG_PCI_OUT) {
1317 		q->u.out.pci_out_enabled = 1;
1318 		qperf_inc(q, pci_request_int);
1319 	} else
1320 		q->u.out.pci_out_enabled = 0;
1321 
1322 	if (queue_type(q) == QDIO_IQDIO_QFMT) {
1323 		unsigned long phys_aob = 0;
1324 
1325 		if (q->u.out.use_cq && count == 1)
1326 			phys_aob = qdio_aob_for_buffer(&q->u.out, bufnr);
1327 
1328 		rc = qdio_kick_outbound_q(q, count, phys_aob);
1329 	} else if (need_siga_sync(q)) {
1330 		rc = qdio_siga_sync_q(q);
1331 	} else if (count < QDIO_MAX_BUFFERS_PER_Q &&
1332 		   get_buf_state(q, prev_buf(bufnr), &state, 0) > 0 &&
1333 		   state == SLSB_CU_OUTPUT_PRIMED) {
1334 		/* The previous buffer is not processed yet, tack on. */
1335 		qperf_inc(q, fast_requeue);
1336 	} else {
1337 		rc = qdio_kick_outbound_q(q, count, 0);
1338 	}
1339 
1340 	/* Let drivers implement their own completion scanning: */
1341 	if (!scan_threshold)
1342 		return rc;
1343 
1344 	/* in case of SIGA errors we must process the error immediately */
1345 	if (used >= scan_threshold || rc)
1346 		qdio_tasklet_schedule(q);
1347 	else
1348 		/* free the SBALs in case of no further traffic */
1349 		if (!timer_pending(&q->u.out.timer) &&
1350 		    likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
1351 			mod_timer(&q->u.out.timer, jiffies + HZ);
1352 	return rc;
1353 }
1354 
1355 /**
1356  * do_QDIO - process input or output buffers
1357  * @cdev: associated ccw_device for the qdio subchannel
1358  * @callflags: input or output and special flags from the program
1359  * @q_nr: queue number
1360  * @bufnr: buffer number
1361  * @count: how many buffers to process
1362  */
1363 int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
1364 	    int q_nr, unsigned int bufnr, unsigned int count)
1365 {
1366 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1367 
1368 	if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1369 		return -EINVAL;
1370 
1371 	if (!irq_ptr)
1372 		return -ENODEV;
1373 
1374 	DBF_DEV_EVENT(DBF_INFO, irq_ptr,
1375 		      "do%02x b:%02x c:%02x", callflags, bufnr, count);
1376 
1377 	if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1378 		return -EIO;
1379 	if (!count)
1380 		return 0;
1381 	if (callflags & QDIO_FLAG_SYNC_INPUT)
1382 		return handle_inbound(irq_ptr->input_qs[q_nr],
1383 				      callflags, bufnr, count);
1384 	else if (callflags & QDIO_FLAG_SYNC_OUTPUT)
1385 		return handle_outbound(irq_ptr->output_qs[q_nr],
1386 				       callflags, bufnr, count);
1387 	return -EINVAL;
1388 }
1389 EXPORT_SYMBOL_GPL(do_QDIO);
1390 
1391 /**
1392  * qdio_start_irq - enable interrupt processing for the device
1393  * @cdev: associated ccw_device for the qdio subchannel
1394  *
1395  * Return codes
1396  *   0 - success
1397  *   1 - irqs not started since new data is available
1398  */
1399 int qdio_start_irq(struct ccw_device *cdev)
1400 {
1401 	struct qdio_q *q;
1402 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1403 	unsigned int i;
1404 
1405 	if (!irq_ptr)
1406 		return -ENODEV;
1407 
1408 	for_each_input_queue(irq_ptr, q, i)
1409 		qdio_stop_polling(q);
1410 
1411 	clear_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state);
1412 
1413 	/*
1414 	 * We need to check again to not lose initiative after
1415 	 * resetting the ACK state.
1416 	 */
1417 	if (test_nonshared_ind(irq_ptr))
1418 		goto rescan;
1419 
1420 	for_each_input_queue(irq_ptr, q, i) {
1421 		if (!qdio_inbound_q_done(q, q->first_to_check))
1422 			goto rescan;
1423 	}
1424 
1425 	return 0;
1426 
1427 rescan:
1428 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1429 		return 0;
1430 	else
1431 		return 1;
1432 
1433 }
1434 EXPORT_SYMBOL(qdio_start_irq);
1435 
1436 static int __qdio_inspect_queue(struct qdio_q *q, unsigned int *bufnr,
1437 				unsigned int *error)
1438 {
1439 	unsigned int start = q->first_to_check;
1440 	int count;
1441 
1442 	*error = 0;
1443 	count = q->is_input_q ? get_inbound_buffer_frontier(q, start, error) :
1444 				get_outbound_buffer_frontier(q, start, error);
1445 	if (count == 0)
1446 		return 0;
1447 
1448 	*bufnr = start;
1449 
1450 	/* for the next time */
1451 	q->first_to_check = add_buf(start, count);
1452 
1453 	return count;
1454 }
1455 
1456 int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, bool is_input,
1457 		       unsigned int *bufnr, unsigned int *error)
1458 {
1459 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1460 	struct qdio_q *q;
1461 
1462 	if (!irq_ptr)
1463 		return -ENODEV;
1464 	q = is_input ? irq_ptr->input_qs[nr] : irq_ptr->output_qs[nr];
1465 
1466 	if (need_siga_sync(q))
1467 		qdio_siga_sync_q(q);
1468 
1469 	return __qdio_inspect_queue(q, bufnr, error);
1470 }
1471 EXPORT_SYMBOL_GPL(qdio_inspect_queue);
1472 
1473 /**
1474  * qdio_get_next_buffers - process input buffers
1475  * @cdev: associated ccw_device for the qdio subchannel
1476  * @nr: input queue number
1477  * @bufnr: first filled buffer number
1478  * @error: buffers are in error state
1479  *
1480  * Return codes
1481  *   < 0 - error
1482  *   = 0 - no new buffers found
1483  *   > 0 - number of processed buffers
1484  */
1485 int qdio_get_next_buffers(struct ccw_device *cdev, int nr, int *bufnr,
1486 			  int *error)
1487 {
1488 	struct qdio_q *q;
1489 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1490 
1491 	if (!irq_ptr)
1492 		return -ENODEV;
1493 	q = irq_ptr->input_qs[nr];
1494 
1495 	/*
1496 	 * Cannot rely on automatic sync after interrupt since queues may
1497 	 * also be examined without interrupt.
1498 	 */
1499 	if (need_siga_sync(q))
1500 		qdio_sync_queues(q);
1501 
1502 	qdio_check_outbound_pci_queues(irq_ptr);
1503 
1504 	/* Note: upper-layer MUST stop processing immediately here ... */
1505 	if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
1506 		return -EIO;
1507 
1508 	return __qdio_inspect_queue(q, bufnr, error);
1509 }
1510 EXPORT_SYMBOL(qdio_get_next_buffers);
1511 
1512 /**
1513  * qdio_stop_irq - disable interrupt processing for the device
1514  * @cdev: associated ccw_device for the qdio subchannel
1515  *
1516  * Return codes
1517  *   0 - interrupts were already disabled
1518  *   1 - interrupts successfully disabled
1519  */
1520 int qdio_stop_irq(struct ccw_device *cdev)
1521 {
1522 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1523 
1524 	if (!irq_ptr)
1525 		return -ENODEV;
1526 
1527 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1528 		return 0;
1529 	else
1530 		return 1;
1531 }
1532 EXPORT_SYMBOL(qdio_stop_irq);
1533 
1534 static int __init init_QDIO(void)
1535 {
1536 	int rc;
1537 
1538 	rc = qdio_debug_init();
1539 	if (rc)
1540 		return rc;
1541 	rc = qdio_setup_init();
1542 	if (rc)
1543 		goto out_debug;
1544 	rc = qdio_thinint_init();
1545 	if (rc)
1546 		goto out_cache;
1547 	return 0;
1548 
1549 out_cache:
1550 	qdio_setup_exit();
1551 out_debug:
1552 	qdio_debug_exit();
1553 	return rc;
1554 }
1555 
1556 static void __exit exit_QDIO(void)
1557 {
1558 	qdio_thinint_exit();
1559 	qdio_setup_exit();
1560 	qdio_debug_exit();
1561 }
1562 
1563 module_init(init_QDIO);
1564 module_exit(exit_QDIO);
1565