xref: /openbmc/linux/drivers/s390/cio/qdio_main.c (revision 249592bf)
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 int qdio_tasklet_schedule(struct qdio_q *q)
521 {
522 	if (likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE)) {
523 		tasklet_schedule(&q->u.out.tasklet);
524 		return 0;
525 	}
526 	return -EPERM;
527 }
528 
529 static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start,
530 					unsigned int *error)
531 {
532 	unsigned char state = 0;
533 	int count;
534 
535 	q->timestamp = get_tod_clock_fast();
536 
537 	if (need_siga_sync(q))
538 		if (((queue_type(q) != QDIO_IQDIO_QFMT) &&
539 		    !pci_out_supported(q->irq_ptr)) ||
540 		    (queue_type(q) == QDIO_IQDIO_QFMT &&
541 		    multicast_outbound(q)))
542 			qdio_siga_sync_q(q);
543 
544 	count = atomic_read(&q->nr_buf_used);
545 	if (!count)
546 		return 0;
547 
548 	count = get_buf_states(q, start, &state, count, 0);
549 	if (!count)
550 		return 0;
551 
552 	switch (state) {
553 	case SLSB_P_OUTPUT_PENDING:
554 		*error = QDIO_ERROR_SLSB_PENDING;
555 		fallthrough;
556 	case SLSB_P_OUTPUT_EMPTY:
557 		/* the adapter got it */
558 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
559 			"out empty:%1d %02x", q->nr, count);
560 
561 		atomic_sub(count, &q->nr_buf_used);
562 		if (q->irq_ptr->perf_stat_enabled)
563 			account_sbals(q, count);
564 		return count;
565 	case SLSB_P_OUTPUT_ERROR:
566 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out error:%1d %02x",
567 			      q->nr, count);
568 
569 		*error = QDIO_ERROR_SLSB_STATE;
570 		process_buffer_error(q, start, count);
571 		atomic_sub(count, &q->nr_buf_used);
572 		if (q->irq_ptr->perf_stat_enabled)
573 			account_sbals_error(q, count);
574 		return count;
575 	case SLSB_CU_OUTPUT_PRIMED:
576 		/* the adapter has not fetched the output yet */
577 		if (q->irq_ptr->perf_stat_enabled)
578 			q->q_stats.nr_sbal_nop++;
579 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out primed:%1d",
580 			      q->nr);
581 		return 0;
582 	case SLSB_P_OUTPUT_HALTED:
583 		return 0;
584 	case SLSB_P_OUTPUT_NOT_INIT:
585 		/* We should never see this state, throw a WARN: */
586 	default:
587 		dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
588 			      "found state %#x at index %u on queue %u\n",
589 			      state, start, q->nr);
590 		return 0;
591 	}
592 }
593 
594 /* all buffers processed? */
595 static inline int qdio_outbound_q_done(struct qdio_q *q)
596 {
597 	return atomic_read(&q->nr_buf_used) == 0;
598 }
599 
600 static int qdio_kick_outbound_q(struct qdio_q *q, unsigned int count,
601 				unsigned long aob)
602 {
603 	int retries = 0, cc;
604 	unsigned int busy_bit;
605 
606 	if (!need_siga_out(q))
607 		return 0;
608 
609 	DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w:%1d", q->nr);
610 retry:
611 	qperf_inc(q, siga_write);
612 
613 	cc = qdio_siga_output(q, count, &busy_bit, aob);
614 	switch (cc) {
615 	case 0:
616 		break;
617 	case 2:
618 		if (busy_bit) {
619 			while (++retries < QDIO_BUSY_BIT_RETRIES) {
620 				mdelay(QDIO_BUSY_BIT_RETRY_DELAY);
621 				goto retry;
622 			}
623 			DBF_ERROR("%4x cc2 BBC:%1d", SCH_NO(q), q->nr);
624 			cc = -EBUSY;
625 		} else {
626 			DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w cc2:%1d", q->nr);
627 			cc = -ENOBUFS;
628 		}
629 		break;
630 	case 1:
631 	case 3:
632 		DBF_ERROR("%4x SIGA-W:%1d", SCH_NO(q), cc);
633 		cc = -EIO;
634 		break;
635 	}
636 	if (retries) {
637 		DBF_ERROR("%4x cc2 BB2:%1d", SCH_NO(q), q->nr);
638 		DBF_ERROR("count:%u", retries);
639 	}
640 	return cc;
641 }
642 
643 void qdio_outbound_tasklet(struct tasklet_struct *t)
644 {
645 	struct qdio_output_q *out_q = from_tasklet(out_q, t, tasklet);
646 	struct qdio_q *q = container_of(out_q, struct qdio_q, u.out);
647 	unsigned int start = q->first_to_check;
648 	unsigned int error = 0;
649 	int count;
650 
651 	qperf_inc(q, tasklet_outbound);
652 	WARN_ON_ONCE(atomic_read(&q->nr_buf_used) < 0);
653 
654 	count = get_outbound_buffer_frontier(q, start, &error);
655 	if (count) {
656 		q->first_to_check = add_buf(start, count);
657 
658 		if (q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE) {
659 			qperf_inc(q, outbound_handler);
660 			DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "koh: s:%02x c:%02x",
661 				      start, count);
662 
663 			q->handler(q->irq_ptr->cdev, error, q->nr, start,
664 				   count, q->irq_ptr->int_parm);
665 		}
666 	}
667 
668 	if (queue_type(q) == QDIO_ZFCP_QFMT && !pci_out_supported(q->irq_ptr) &&
669 	    !qdio_outbound_q_done(q))
670 		goto sched;
671 
672 	if (q->u.out.pci_out_enabled)
673 		return;
674 
675 	/*
676 	 * Now we know that queue type is either qeth without pci enabled
677 	 * or HiperSockets. Make sure buffer switch from PRIMED to EMPTY
678 	 * is noticed and outbound_handler is called after some time.
679 	 */
680 	if (qdio_outbound_q_done(q))
681 		del_timer_sync(&q->u.out.timer);
682 	else
683 		if (!timer_pending(&q->u.out.timer) &&
684 		    likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
685 			mod_timer(&q->u.out.timer, jiffies + 10 * HZ);
686 	return;
687 
688 sched:
689 	qdio_tasklet_schedule(q);
690 }
691 
692 void qdio_outbound_timer(struct timer_list *t)
693 {
694 	struct qdio_q *q = from_timer(q, t, u.out.timer);
695 
696 	qdio_tasklet_schedule(q);
697 }
698 
699 static inline void qdio_check_outbound_pci_queues(struct qdio_irq *irq)
700 {
701 	struct qdio_q *out;
702 	int i;
703 
704 	if (!pci_out_supported(irq) || !irq->scan_threshold)
705 		return;
706 
707 	for_each_output_queue(irq, out, i)
708 		if (!qdio_outbound_q_done(out))
709 			qdio_tasklet_schedule(out);
710 }
711 
712 static inline void qdio_set_state(struct qdio_irq *irq_ptr,
713 				  enum qdio_irq_states state)
714 {
715 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "newstate: %1d", state);
716 
717 	irq_ptr->state = state;
718 	mb();
719 }
720 
721 static void qdio_irq_check_sense(struct qdio_irq *irq_ptr, struct irb *irb)
722 {
723 	if (irb->esw.esw0.erw.cons) {
724 		DBF_ERROR("%4x sense:", irq_ptr->schid.sch_no);
725 		DBF_ERROR_HEX(irb, 64);
726 		DBF_ERROR_HEX(irb->ecw, 64);
727 	}
728 }
729 
730 /* PCI interrupt handler */
731 static void qdio_int_handler_pci(struct qdio_irq *irq_ptr)
732 {
733 	int i;
734 	struct qdio_q *q;
735 
736 	if (unlikely(irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
737 		return;
738 
739 	qdio_deliver_irq(irq_ptr);
740 	irq_ptr->last_data_irq_time = S390_lowcore.int_clock;
741 
742 	if (!pci_out_supported(irq_ptr) || !irq_ptr->scan_threshold)
743 		return;
744 
745 	for_each_output_queue(irq_ptr, q, i) {
746 		if (qdio_outbound_q_done(q))
747 			continue;
748 		if (need_siga_sync(q) && need_siga_sync_out_after_pci(q))
749 			qdio_siga_sync_q(q);
750 		qdio_tasklet_schedule(q);
751 	}
752 }
753 
754 static void qdio_handle_activate_check(struct qdio_irq *irq_ptr,
755 				       unsigned long intparm, int cstat,
756 				       int dstat)
757 {
758 	struct qdio_q *q;
759 
760 	DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
761 	DBF_ERROR("intp :%lx", intparm);
762 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
763 
764 	if (irq_ptr->nr_input_qs) {
765 		q = irq_ptr->input_qs[0];
766 	} else if (irq_ptr->nr_output_qs) {
767 		q = irq_ptr->output_qs[0];
768 	} else {
769 		dump_stack();
770 		goto no_handler;
771 	}
772 
773 	q->handler(q->irq_ptr->cdev, QDIO_ERROR_ACTIVATE,
774 		   q->nr, q->first_to_check, 0, irq_ptr->int_parm);
775 no_handler:
776 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
777 	/*
778 	 * In case of z/VM LGR (Live Guest Migration) QDIO recovery will happen.
779 	 * Therefore we call the LGR detection function here.
780 	 */
781 	lgr_info_log();
782 }
783 
784 static void qdio_establish_handle_irq(struct qdio_irq *irq_ptr, int cstat,
785 				      int dstat)
786 {
787 	DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qest irq");
788 
789 	if (cstat)
790 		goto error;
791 	if (dstat & ~(DEV_STAT_DEV_END | DEV_STAT_CHN_END))
792 		goto error;
793 	if (!(dstat & DEV_STAT_DEV_END))
794 		goto error;
795 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ESTABLISHED);
796 	return;
797 
798 error:
799 	DBF_ERROR("%4x EQ:error", irq_ptr->schid.sch_no);
800 	DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
801 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
802 }
803 
804 /* qdio interrupt handler */
805 void qdio_int_handler(struct ccw_device *cdev, unsigned long intparm,
806 		      struct irb *irb)
807 {
808 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
809 	struct subchannel_id schid;
810 	int cstat, dstat;
811 
812 	if (!intparm || !irq_ptr) {
813 		ccw_device_get_schid(cdev, &schid);
814 		DBF_ERROR("qint:%4x", schid.sch_no);
815 		return;
816 	}
817 
818 	if (irq_ptr->perf_stat_enabled)
819 		irq_ptr->perf_stat.qdio_int++;
820 
821 	if (IS_ERR(irb)) {
822 		DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
823 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
824 		wake_up(&cdev->private->wait_q);
825 		return;
826 	}
827 	qdio_irq_check_sense(irq_ptr, irb);
828 	cstat = irb->scsw.cmd.cstat;
829 	dstat = irb->scsw.cmd.dstat;
830 
831 	switch (irq_ptr->state) {
832 	case QDIO_IRQ_STATE_INACTIVE:
833 		qdio_establish_handle_irq(irq_ptr, cstat, dstat);
834 		break;
835 	case QDIO_IRQ_STATE_CLEANUP:
836 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
837 		break;
838 	case QDIO_IRQ_STATE_ESTABLISHED:
839 	case QDIO_IRQ_STATE_ACTIVE:
840 		if (cstat & SCHN_STAT_PCI) {
841 			qdio_int_handler_pci(irq_ptr);
842 			return;
843 		}
844 		if (cstat || dstat)
845 			qdio_handle_activate_check(irq_ptr, intparm, cstat,
846 						   dstat);
847 		break;
848 	case QDIO_IRQ_STATE_STOPPED:
849 		break;
850 	default:
851 		WARN_ON_ONCE(1);
852 	}
853 	wake_up(&cdev->private->wait_q);
854 }
855 
856 /**
857  * qdio_get_ssqd_desc - get qdio subchannel description
858  * @cdev: ccw device to get description for
859  * @data: where to store the ssqd
860  *
861  * Returns 0 or an error code. The results of the chsc are stored in the
862  * specified structure.
863  */
864 int qdio_get_ssqd_desc(struct ccw_device *cdev,
865 		       struct qdio_ssqd_desc *data)
866 {
867 	struct subchannel_id schid;
868 
869 	if (!cdev || !cdev->private)
870 		return -EINVAL;
871 
872 	ccw_device_get_schid(cdev, &schid);
873 	DBF_EVENT("get ssqd:%4x", schid.sch_no);
874 	return qdio_setup_get_ssqd(NULL, &schid, data);
875 }
876 EXPORT_SYMBOL_GPL(qdio_get_ssqd_desc);
877 
878 static void qdio_shutdown_queues(struct qdio_irq *irq_ptr)
879 {
880 	struct qdio_q *q;
881 	int i;
882 
883 	for_each_output_queue(irq_ptr, q, i) {
884 		del_timer_sync(&q->u.out.timer);
885 		tasklet_kill(&q->u.out.tasklet);
886 	}
887 }
888 
889 /**
890  * qdio_shutdown - shut down a qdio subchannel
891  * @cdev: associated ccw device
892  * @how: use halt or clear to shutdown
893  */
894 int qdio_shutdown(struct ccw_device *cdev, int how)
895 {
896 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
897 	struct subchannel_id schid;
898 	int rc;
899 
900 	if (!irq_ptr)
901 		return -ENODEV;
902 
903 	WARN_ON_ONCE(irqs_disabled());
904 	ccw_device_get_schid(cdev, &schid);
905 	DBF_EVENT("qshutdown:%4x", schid.sch_no);
906 
907 	mutex_lock(&irq_ptr->setup_mutex);
908 	/*
909 	 * Subchannel was already shot down. We cannot prevent being called
910 	 * twice since cio may trigger a shutdown asynchronously.
911 	 */
912 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
913 		mutex_unlock(&irq_ptr->setup_mutex);
914 		return 0;
915 	}
916 
917 	/*
918 	 * Indicate that the device is going down. Scheduling the queue
919 	 * tasklets is forbidden from here on.
920 	 */
921 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
922 
923 	qdio_shutdown_queues(irq_ptr);
924 	qdio_shutdown_debug_entries(irq_ptr);
925 
926 	/* cleanup subchannel */
927 	spin_lock_irq(get_ccwdev_lock(cdev));
928 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_CLEANUP);
929 	if (how & QDIO_FLAG_CLEANUP_USING_CLEAR)
930 		rc = ccw_device_clear(cdev, QDIO_DOING_CLEANUP);
931 	else
932 		/* default behaviour is halt */
933 		rc = ccw_device_halt(cdev, QDIO_DOING_CLEANUP);
934 	spin_unlock_irq(get_ccwdev_lock(cdev));
935 	if (rc) {
936 		DBF_ERROR("%4x SHUTD ERR", irq_ptr->schid.sch_no);
937 		DBF_ERROR("rc:%4d", rc);
938 		goto no_cleanup;
939 	}
940 
941 	wait_event_interruptible_timeout(cdev->private->wait_q,
942 		irq_ptr->state == QDIO_IRQ_STATE_INACTIVE ||
943 		irq_ptr->state == QDIO_IRQ_STATE_ERR,
944 		10 * HZ);
945 
946 no_cleanup:
947 	qdio_shutdown_thinint(irq_ptr);
948 	qdio_shutdown_irq(irq_ptr);
949 
950 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
951 	mutex_unlock(&irq_ptr->setup_mutex);
952 	if (rc)
953 		return rc;
954 	return 0;
955 }
956 EXPORT_SYMBOL_GPL(qdio_shutdown);
957 
958 /**
959  * qdio_free - free data structures for a qdio subchannel
960  * @cdev: associated ccw device
961  */
962 int qdio_free(struct ccw_device *cdev)
963 {
964 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
965 	struct subchannel_id schid;
966 
967 	if (!irq_ptr)
968 		return -ENODEV;
969 
970 	ccw_device_get_schid(cdev, &schid);
971 	DBF_EVENT("qfree:%4x", schid.sch_no);
972 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf abandoned");
973 	mutex_lock(&irq_ptr->setup_mutex);
974 
975 	irq_ptr->debug_area = NULL;
976 	cdev->private->qdio_data = NULL;
977 	mutex_unlock(&irq_ptr->setup_mutex);
978 
979 	qdio_free_queues(irq_ptr);
980 	free_page((unsigned long) irq_ptr->qdr);
981 	free_page(irq_ptr->chsc_page);
982 	free_page((unsigned long) irq_ptr);
983 	return 0;
984 }
985 EXPORT_SYMBOL_GPL(qdio_free);
986 
987 /**
988  * qdio_allocate - allocate qdio queues and associated data
989  * @cdev: associated ccw device
990  * @no_input_qs: allocate this number of Input Queues
991  * @no_output_qs: allocate this number of Output Queues
992  */
993 int qdio_allocate(struct ccw_device *cdev, unsigned int no_input_qs,
994 		  unsigned int no_output_qs)
995 {
996 	struct subchannel_id schid;
997 	struct qdio_irq *irq_ptr;
998 	int rc = -ENOMEM;
999 
1000 	ccw_device_get_schid(cdev, &schid);
1001 	DBF_EVENT("qallocate:%4x", schid.sch_no);
1002 
1003 	if (no_input_qs > QDIO_MAX_QUEUES_PER_IRQ ||
1004 	    no_output_qs > QDIO_MAX_QUEUES_PER_IRQ)
1005 		return -EINVAL;
1006 
1007 	/* irq_ptr must be in GFP_DMA since it contains ccw1.cda */
1008 	irq_ptr = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1009 	if (!irq_ptr)
1010 		return -ENOMEM;
1011 
1012 	irq_ptr->cdev = cdev;
1013 	mutex_init(&irq_ptr->setup_mutex);
1014 	if (qdio_allocate_dbf(irq_ptr))
1015 		goto err_dbf;
1016 
1017 	DBF_DEV_EVENT(DBF_ERR, irq_ptr, "alloc niq:%1u noq:%1u", no_input_qs,
1018 		      no_output_qs);
1019 
1020 	/*
1021 	 * Allocate a page for the chsc calls in qdio_establish.
1022 	 * Must be pre-allocated since a zfcp recovery will call
1023 	 * qdio_establish. In case of low memory and swap on a zfcp disk
1024 	 * we may not be able to allocate memory otherwise.
1025 	 */
1026 	irq_ptr->chsc_page = get_zeroed_page(GFP_KERNEL);
1027 	if (!irq_ptr->chsc_page)
1028 		goto err_chsc;
1029 
1030 	/* qdr is used in ccw1.cda which is u32 */
1031 	irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1032 	if (!irq_ptr->qdr)
1033 		goto err_qdr;
1034 
1035 	rc = qdio_allocate_qs(irq_ptr, no_input_qs, no_output_qs);
1036 	if (rc)
1037 		goto err_queues;
1038 
1039 	cdev->private->qdio_data = irq_ptr;
1040 	qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1041 	return 0;
1042 
1043 err_queues:
1044 	free_page((unsigned long) irq_ptr->qdr);
1045 err_qdr:
1046 	free_page(irq_ptr->chsc_page);
1047 err_chsc:
1048 err_dbf:
1049 	free_page((unsigned long) irq_ptr);
1050 	return rc;
1051 }
1052 EXPORT_SYMBOL_GPL(qdio_allocate);
1053 
1054 static void qdio_trace_init_data(struct qdio_irq *irq,
1055 				 struct qdio_initialize *data)
1056 {
1057 	DBF_DEV_EVENT(DBF_ERR, irq, "qfmt:%1u", data->q_format);
1058 	DBF_DEV_EVENT(DBF_ERR, irq, "qpff%4x", data->qib_param_field_format);
1059 	DBF_DEV_HEX(irq, &data->qib_param_field, sizeof(void *), DBF_ERR);
1060 	DBF_DEV_HEX(irq, &data->input_slib_elements, sizeof(void *), DBF_ERR);
1061 	DBF_DEV_HEX(irq, &data->output_slib_elements, sizeof(void *), DBF_ERR);
1062 	DBF_DEV_EVENT(DBF_ERR, irq, "niq:%1u noq:%1u", data->no_input_qs,
1063 		      data->no_output_qs);
1064 	DBF_DEV_HEX(irq, &data->input_handler, sizeof(void *), DBF_ERR);
1065 	DBF_DEV_HEX(irq, &data->output_handler, sizeof(void *), DBF_ERR);
1066 	DBF_DEV_HEX(irq, &data->int_parm, sizeof(long), DBF_ERR);
1067 	DBF_DEV_HEX(irq, &data->input_sbal_addr_array, sizeof(void *), DBF_ERR);
1068 	DBF_DEV_HEX(irq, &data->output_sbal_addr_array, sizeof(void *),
1069 		    DBF_ERR);
1070 }
1071 
1072 /**
1073  * qdio_establish - establish queues on a qdio subchannel
1074  * @cdev: associated ccw device
1075  * @init_data: initialization data
1076  */
1077 int qdio_establish(struct ccw_device *cdev,
1078 		   struct qdio_initialize *init_data)
1079 {
1080 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1081 	struct subchannel_id schid;
1082 	int rc;
1083 
1084 	ccw_device_get_schid(cdev, &schid);
1085 	DBF_EVENT("qestablish:%4x", schid.sch_no);
1086 
1087 	if (!irq_ptr)
1088 		return -ENODEV;
1089 
1090 	if (init_data->no_input_qs > irq_ptr->max_input_qs ||
1091 	    init_data->no_output_qs > irq_ptr->max_output_qs)
1092 		return -EINVAL;
1093 
1094 	if ((init_data->no_input_qs && !init_data->input_handler) ||
1095 	    (init_data->no_output_qs && !init_data->output_handler))
1096 		return -EINVAL;
1097 
1098 	if (!init_data->input_sbal_addr_array ||
1099 	    !init_data->output_sbal_addr_array)
1100 		return -EINVAL;
1101 
1102 	if (!init_data->irq_poll)
1103 		return -EINVAL;
1104 
1105 	mutex_lock(&irq_ptr->setup_mutex);
1106 	qdio_trace_init_data(irq_ptr, init_data);
1107 	qdio_setup_irq(irq_ptr, init_data);
1108 
1109 	rc = qdio_establish_thinint(irq_ptr);
1110 	if (rc) {
1111 		qdio_shutdown_irq(irq_ptr);
1112 		mutex_unlock(&irq_ptr->setup_mutex);
1113 		return rc;
1114 	}
1115 
1116 	/* establish q */
1117 	irq_ptr->ccw.cmd_code = irq_ptr->equeue.cmd;
1118 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1119 	irq_ptr->ccw.count = irq_ptr->equeue.count;
1120 	irq_ptr->ccw.cda = (u32)((addr_t)irq_ptr->qdr);
1121 
1122 	spin_lock_irq(get_ccwdev_lock(cdev));
1123 	ccw_device_set_options_mask(cdev, 0);
1124 
1125 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ESTABLISH, 0, 0);
1126 	spin_unlock_irq(get_ccwdev_lock(cdev));
1127 	if (rc) {
1128 		DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no);
1129 		DBF_ERROR("rc:%4x", rc);
1130 		qdio_shutdown_thinint(irq_ptr);
1131 		qdio_shutdown_irq(irq_ptr);
1132 		mutex_unlock(&irq_ptr->setup_mutex);
1133 		return rc;
1134 	}
1135 
1136 	wait_event_interruptible_timeout(cdev->private->wait_q,
1137 		irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
1138 		irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ);
1139 
1140 	if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) {
1141 		mutex_unlock(&irq_ptr->setup_mutex);
1142 		qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
1143 		return -EIO;
1144 	}
1145 
1146 	qdio_setup_ssqd_info(irq_ptr);
1147 
1148 	/* qebsm is now setup if available, initialize buffer states */
1149 	qdio_init_buf_states(irq_ptr);
1150 
1151 	mutex_unlock(&irq_ptr->setup_mutex);
1152 	qdio_print_subchannel_info(irq_ptr);
1153 	qdio_setup_debug_entries(irq_ptr);
1154 	return 0;
1155 }
1156 EXPORT_SYMBOL_GPL(qdio_establish);
1157 
1158 /**
1159  * qdio_activate - activate queues on a qdio subchannel
1160  * @cdev: associated cdev
1161  */
1162 int qdio_activate(struct ccw_device *cdev)
1163 {
1164 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1165 	struct subchannel_id schid;
1166 	int rc;
1167 
1168 	ccw_device_get_schid(cdev, &schid);
1169 	DBF_EVENT("qactivate:%4x", schid.sch_no);
1170 
1171 	if (!irq_ptr)
1172 		return -ENODEV;
1173 
1174 	mutex_lock(&irq_ptr->setup_mutex);
1175 	if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1176 		rc = -EBUSY;
1177 		goto out;
1178 	}
1179 
1180 	irq_ptr->ccw.cmd_code = irq_ptr->aqueue.cmd;
1181 	irq_ptr->ccw.flags = CCW_FLAG_SLI;
1182 	irq_ptr->ccw.count = irq_ptr->aqueue.count;
1183 	irq_ptr->ccw.cda = 0;
1184 
1185 	spin_lock_irq(get_ccwdev_lock(cdev));
1186 	ccw_device_set_options(cdev, CCWDEV_REPORT_ALL);
1187 
1188 	rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ACTIVATE,
1189 			      0, DOIO_DENY_PREFETCH);
1190 	spin_unlock_irq(get_ccwdev_lock(cdev));
1191 	if (rc) {
1192 		DBF_ERROR("%4x act IO ERR", irq_ptr->schid.sch_no);
1193 		DBF_ERROR("rc:%4x", rc);
1194 		goto out;
1195 	}
1196 
1197 	/* wait for subchannel to become active */
1198 	msleep(5);
1199 
1200 	switch (irq_ptr->state) {
1201 	case QDIO_IRQ_STATE_STOPPED:
1202 	case QDIO_IRQ_STATE_ERR:
1203 		rc = -EIO;
1204 		break;
1205 	default:
1206 		qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ACTIVE);
1207 		rc = 0;
1208 	}
1209 out:
1210 	mutex_unlock(&irq_ptr->setup_mutex);
1211 	return rc;
1212 }
1213 EXPORT_SYMBOL_GPL(qdio_activate);
1214 
1215 /**
1216  * handle_inbound - reset processed input buffers
1217  * @q: queue containing the buffers
1218  * @callflags: flags
1219  * @bufnr: first buffer to process
1220  * @count: how many buffers are emptied
1221  */
1222 static int handle_inbound(struct qdio_q *q, unsigned int callflags,
1223 			  int bufnr, int count)
1224 {
1225 	int overlap;
1226 
1227 	qperf_inc(q, inbound_call);
1228 
1229 	/* If any processed SBALs are returned to HW, adjust our tracking: */
1230 	overlap = min_t(int, count - sub_buf(q->u.in.batch_start, bufnr),
1231 			     q->u.in.batch_count);
1232 	if (overlap > 0) {
1233 		q->u.in.batch_start = add_buf(q->u.in.batch_start, overlap);
1234 		q->u.in.batch_count -= overlap;
1235 	}
1236 
1237 	count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
1238 	atomic_add(count, &q->nr_buf_used);
1239 
1240 	if (need_siga_in(q))
1241 		return qdio_siga_input(q);
1242 
1243 	return 0;
1244 }
1245 
1246 /**
1247  * handle_outbound - process filled outbound buffers
1248  * @q: queue containing the buffers
1249  * @callflags: flags
1250  * @bufnr: first buffer to process
1251  * @count: how many buffers are filled
1252  * @aob: asynchronous operation block
1253  */
1254 static int handle_outbound(struct qdio_q *q, unsigned int callflags,
1255 			   unsigned int bufnr, unsigned int count,
1256 			   struct qaob *aob)
1257 {
1258 	const unsigned int scan_threshold = q->irq_ptr->scan_threshold;
1259 	unsigned char state = 0;
1260 	int used, rc = 0;
1261 
1262 	qperf_inc(q, outbound_call);
1263 
1264 	count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
1265 	used = atomic_add_return(count, &q->nr_buf_used);
1266 
1267 	if (used == QDIO_MAX_BUFFERS_PER_Q)
1268 		qperf_inc(q, outbound_queue_full);
1269 
1270 	if (callflags & QDIO_FLAG_PCI_OUT) {
1271 		q->u.out.pci_out_enabled = 1;
1272 		qperf_inc(q, pci_request_int);
1273 	} else
1274 		q->u.out.pci_out_enabled = 0;
1275 
1276 	if (queue_type(q) == QDIO_IQDIO_QFMT) {
1277 		unsigned long phys_aob = aob ? virt_to_phys(aob) : 0;
1278 
1279 		WARN_ON_ONCE(!IS_ALIGNED(phys_aob, 256));
1280 		rc = qdio_kick_outbound_q(q, count, phys_aob);
1281 	} else if (need_siga_sync(q)) {
1282 		rc = qdio_siga_sync_q(q);
1283 	} else if (count < QDIO_MAX_BUFFERS_PER_Q &&
1284 		   get_buf_state(q, prev_buf(bufnr), &state, 0) > 0 &&
1285 		   state == SLSB_CU_OUTPUT_PRIMED) {
1286 		/* The previous buffer is not processed yet, tack on. */
1287 		qperf_inc(q, fast_requeue);
1288 	} else {
1289 		rc = qdio_kick_outbound_q(q, count, 0);
1290 	}
1291 
1292 	/* Let drivers implement their own completion scanning: */
1293 	if (!scan_threshold)
1294 		return rc;
1295 
1296 	/* in case of SIGA errors we must process the error immediately */
1297 	if (used >= scan_threshold || rc)
1298 		qdio_tasklet_schedule(q);
1299 	else
1300 		/* free the SBALs in case of no further traffic */
1301 		if (!timer_pending(&q->u.out.timer) &&
1302 		    likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
1303 			mod_timer(&q->u.out.timer, jiffies + HZ);
1304 	return rc;
1305 }
1306 
1307 /**
1308  * do_QDIO - process input or output buffers
1309  * @cdev: associated ccw_device for the qdio subchannel
1310  * @callflags: input or output and special flags from the program
1311  * @q_nr: queue number
1312  * @bufnr: buffer number
1313  * @count: how many buffers to process
1314  * @aob: asynchronous operation block (outbound only)
1315  */
1316 int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
1317 	    int q_nr, unsigned int bufnr, unsigned int count, struct qaob *aob)
1318 {
1319 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1320 
1321 	if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1322 		return -EINVAL;
1323 
1324 	if (!irq_ptr)
1325 		return -ENODEV;
1326 
1327 	DBF_DEV_EVENT(DBF_INFO, irq_ptr,
1328 		      "do%02x b:%02x c:%02x", callflags, bufnr, count);
1329 
1330 	if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1331 		return -EIO;
1332 	if (!count)
1333 		return 0;
1334 	if (callflags & QDIO_FLAG_SYNC_INPUT)
1335 		return handle_inbound(irq_ptr->input_qs[q_nr],
1336 				      callflags, bufnr, count);
1337 	else if (callflags & QDIO_FLAG_SYNC_OUTPUT)
1338 		return handle_outbound(irq_ptr->output_qs[q_nr],
1339 				       callflags, bufnr, count, aob);
1340 	return -EINVAL;
1341 }
1342 EXPORT_SYMBOL_GPL(do_QDIO);
1343 
1344 /**
1345  * qdio_start_irq - enable interrupt processing for the device
1346  * @cdev: associated ccw_device for the qdio subchannel
1347  *
1348  * Return codes
1349  *   0 - success
1350  *   1 - irqs not started since new data is available
1351  */
1352 int qdio_start_irq(struct ccw_device *cdev)
1353 {
1354 	struct qdio_q *q;
1355 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1356 	unsigned int i;
1357 
1358 	if (!irq_ptr)
1359 		return -ENODEV;
1360 
1361 	for_each_input_queue(irq_ptr, q, i)
1362 		qdio_stop_polling(q);
1363 
1364 	clear_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state);
1365 
1366 	/*
1367 	 * We need to check again to not lose initiative after
1368 	 * resetting the ACK state.
1369 	 */
1370 	if (test_nonshared_ind(irq_ptr))
1371 		goto rescan;
1372 
1373 	for_each_input_queue(irq_ptr, q, i) {
1374 		if (!qdio_inbound_q_done(q, q->first_to_check))
1375 			goto rescan;
1376 	}
1377 
1378 	return 0;
1379 
1380 rescan:
1381 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1382 		return 0;
1383 	else
1384 		return 1;
1385 
1386 }
1387 EXPORT_SYMBOL(qdio_start_irq);
1388 
1389 static int __qdio_inspect_queue(struct qdio_q *q, unsigned int *bufnr,
1390 				unsigned int *error)
1391 {
1392 	unsigned int start = q->first_to_check;
1393 	int count;
1394 
1395 	*error = 0;
1396 	count = q->is_input_q ? get_inbound_buffer_frontier(q, start, error) :
1397 				get_outbound_buffer_frontier(q, start, error);
1398 	if (count == 0)
1399 		return 0;
1400 
1401 	*bufnr = start;
1402 
1403 	/* for the next time */
1404 	q->first_to_check = add_buf(start, count);
1405 
1406 	return count;
1407 }
1408 
1409 int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, bool is_input,
1410 		       unsigned int *bufnr, unsigned int *error)
1411 {
1412 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1413 	struct qdio_q *q;
1414 
1415 	if (!irq_ptr)
1416 		return -ENODEV;
1417 	q = is_input ? irq_ptr->input_qs[nr] : irq_ptr->output_qs[nr];
1418 
1419 	if (need_siga_sync(q))
1420 		qdio_siga_sync_q(q);
1421 
1422 	return __qdio_inspect_queue(q, bufnr, error);
1423 }
1424 EXPORT_SYMBOL_GPL(qdio_inspect_queue);
1425 
1426 /**
1427  * qdio_get_next_buffers - process input buffers
1428  * @cdev: associated ccw_device for the qdio subchannel
1429  * @nr: input queue number
1430  * @bufnr: first filled buffer number
1431  * @error: buffers are in error state
1432  *
1433  * Return codes
1434  *   < 0 - error
1435  *   = 0 - no new buffers found
1436  *   > 0 - number of processed buffers
1437  */
1438 int qdio_get_next_buffers(struct ccw_device *cdev, int nr, int *bufnr,
1439 			  int *error)
1440 {
1441 	struct qdio_q *q;
1442 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1443 
1444 	if (!irq_ptr)
1445 		return -ENODEV;
1446 	q = irq_ptr->input_qs[nr];
1447 
1448 	/*
1449 	 * Cannot rely on automatic sync after interrupt since queues may
1450 	 * also be examined without interrupt.
1451 	 */
1452 	if (need_siga_sync(q))
1453 		qdio_sync_queues(q);
1454 
1455 	qdio_check_outbound_pci_queues(irq_ptr);
1456 
1457 	/* Note: upper-layer MUST stop processing immediately here ... */
1458 	if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
1459 		return -EIO;
1460 
1461 	return __qdio_inspect_queue(q, bufnr, error);
1462 }
1463 EXPORT_SYMBOL(qdio_get_next_buffers);
1464 
1465 /**
1466  * qdio_stop_irq - disable interrupt processing for the device
1467  * @cdev: associated ccw_device for the qdio subchannel
1468  *
1469  * Return codes
1470  *   0 - interrupts were already disabled
1471  *   1 - interrupts successfully disabled
1472  */
1473 int qdio_stop_irq(struct ccw_device *cdev)
1474 {
1475 	struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1476 
1477 	if (!irq_ptr)
1478 		return -ENODEV;
1479 
1480 	if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1481 		return 0;
1482 	else
1483 		return 1;
1484 }
1485 EXPORT_SYMBOL(qdio_stop_irq);
1486 
1487 static int __init init_QDIO(void)
1488 {
1489 	int rc;
1490 
1491 	rc = qdio_debug_init();
1492 	if (rc)
1493 		return rc;
1494 	rc = qdio_setup_init();
1495 	if (rc)
1496 		goto out_debug;
1497 	rc = qdio_thinint_init();
1498 	if (rc)
1499 		goto out_cache;
1500 	return 0;
1501 
1502 out_cache:
1503 	qdio_setup_exit();
1504 out_debug:
1505 	qdio_debug_exit();
1506 	return rc;
1507 }
1508 
1509 static void __exit exit_QDIO(void)
1510 {
1511 	qdio_thinint_exit();
1512 	qdio_setup_exit();
1513 	qdio_debug_exit();
1514 }
1515 
1516 module_init(init_QDIO);
1517 module_exit(exit_QDIO);
1518