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13#include <linux/kernel_stat.h>
14#include <linux/init.h>
15#include <linux/bootmem.h>
16#include <linux/err.h>
17#include <linux/virtio.h>
18#include <linux/virtio_config.h>
19#include <linux/slab.h>
20#include <linux/interrupt.h>
21#include <linux/virtio_ring.h>
22#include <linux/pfn.h>
23#include <linux/async.h>
24#include <linux/wait.h>
25#include <linux/list.h>
26#include <linux/bitops.h>
27#include <linux/moduleparam.h>
28#include <linux/io.h>
29#include <linux/kvm_para.h>
30#include <linux/notifier.h>
31#include <asm/setup.h>
32#include <asm/irq.h>
33#include <asm/cio.h>
34#include <asm/ccwdev.h>
35#include <asm/virtio-ccw.h>
36#include <asm/isc.h>
37#include <asm/airq.h>
38
39
40
41
42
43struct vq_config_block {
44 __u16 index;
45 __u16 num;
46} __packed;
47
48#define VIRTIO_CCW_CONFIG_SIZE 0x100
49
50
51struct virtio_ccw_device {
52 struct virtio_device vdev;
53 __u8 *status;
54 __u8 config[VIRTIO_CCW_CONFIG_SIZE];
55 struct ccw_device *cdev;
56 __u32 curr_io;
57 int err;
58 unsigned int revision;
59 wait_queue_head_t wait_q;
60 spinlock_t lock;
61 struct list_head virtqueues;
62 unsigned long indicators;
63 unsigned long indicators2;
64 struct vq_config_block *config_block;
65 bool is_thinint;
66 bool going_away;
67 bool device_lost;
68 unsigned int config_ready;
69 void *airq_info;
70};
71
72struct vq_info_block_legacy {
73 __u64 queue;
74 __u32 align;
75 __u16 index;
76 __u16 num;
77} __packed;
78
79struct vq_info_block {
80 __u64 desc;
81 __u32 res0;
82 __u16 index;
83 __u16 num;
84 __u64 avail;
85 __u64 used;
86} __packed;
87
88struct virtio_feature_desc {
89 __le32 features;
90 __u8 index;
91} __packed;
92
93struct virtio_thinint_area {
94 unsigned long summary_indicator;
95 unsigned long indicator;
96 u64 bit_nr;
97 u8 isc;
98} __packed;
99
100struct virtio_rev_info {
101 __u16 revision;
102 __u16 length;
103 __u8 data[];
104};
105
106
107#define VIRTIO_CCW_REV_MAX 1
108
109struct virtio_ccw_vq_info {
110 struct virtqueue *vq;
111 int num;
112 void *queue;
113 union {
114 struct vq_info_block s;
115 struct vq_info_block_legacy l;
116 } *info_block;
117 int bit_nr;
118 struct list_head node;
119 long cookie;
120};
121
122#define VIRTIO_AIRQ_ISC IO_SCH_ISC
123
124#define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
125#define MAX_AIRQ_AREAS 20
126
127static int virtio_ccw_use_airq = 1;
128
129struct airq_info {
130 rwlock_t lock;
131 u8 summary_indicator;
132 struct airq_struct airq;
133 struct airq_iv *aiv;
134};
135static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
136
137#define CCW_CMD_SET_VQ 0x13
138#define CCW_CMD_VDEV_RESET 0x33
139#define CCW_CMD_SET_IND 0x43
140#define CCW_CMD_SET_CONF_IND 0x53
141#define CCW_CMD_READ_FEAT 0x12
142#define CCW_CMD_WRITE_FEAT 0x11
143#define CCW_CMD_READ_CONF 0x22
144#define CCW_CMD_WRITE_CONF 0x21
145#define CCW_CMD_WRITE_STATUS 0x31
146#define CCW_CMD_READ_VQ_CONF 0x32
147#define CCW_CMD_READ_STATUS 0x72
148#define CCW_CMD_SET_IND_ADAPTER 0x73
149#define CCW_CMD_SET_VIRTIO_REV 0x83
150
151#define VIRTIO_CCW_DOING_SET_VQ 0x00010000
152#define VIRTIO_CCW_DOING_RESET 0x00040000
153#define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
154#define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
155#define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
156#define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
157#define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
158#define VIRTIO_CCW_DOING_SET_IND 0x01000000
159#define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
160#define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
161#define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
162#define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
163#define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
164#define VIRTIO_CCW_INTPARM_MASK 0xffff0000
165
166static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
167{
168 return container_of(vdev, struct virtio_ccw_device, vdev);
169}
170
171static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
172{
173 unsigned long i, flags;
174
175 write_lock_irqsave(&info->lock, flags);
176 for (i = 0; i < airq_iv_end(info->aiv); i++) {
177 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
178 airq_iv_free_bit(info->aiv, i);
179 airq_iv_set_ptr(info->aiv, i, 0);
180 break;
181 }
182 }
183 write_unlock_irqrestore(&info->lock, flags);
184}
185
186static void virtio_airq_handler(struct airq_struct *airq)
187{
188 struct airq_info *info = container_of(airq, struct airq_info, airq);
189 unsigned long ai;
190
191 inc_irq_stat(IRQIO_VAI);
192 read_lock(&info->lock);
193
194 for (ai = 0;;) {
195 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
196 if (ai == -1UL)
197 break;
198 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
199 }
200 info->summary_indicator = 0;
201 smp_wmb();
202
203 for (ai = 0;;) {
204 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
205 if (ai == -1UL)
206 break;
207 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
208 }
209 read_unlock(&info->lock);
210}
211
212static struct airq_info *new_airq_info(void)
213{
214 struct airq_info *info;
215 int rc;
216
217 info = kzalloc(sizeof(*info), GFP_KERNEL);
218 if (!info)
219 return NULL;
220 rwlock_init(&info->lock);
221 info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
222 if (!info->aiv) {
223 kfree(info);
224 return NULL;
225 }
226 info->airq.handler = virtio_airq_handler;
227 info->airq.lsi_ptr = &info->summary_indicator;
228 info->airq.lsi_mask = 0xff;
229 info->airq.isc = VIRTIO_AIRQ_ISC;
230 rc = register_adapter_interrupt(&info->airq);
231 if (rc) {
232 airq_iv_release(info->aiv);
233 kfree(info);
234 return NULL;
235 }
236 return info;
237}
238
239static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
240 u64 *first, void **airq_info)
241{
242 int i, j;
243 struct airq_info *info;
244 unsigned long indicator_addr = 0;
245 unsigned long bit, flags;
246
247 for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
248 if (!airq_areas[i])
249 airq_areas[i] = new_airq_info();
250 info = airq_areas[i];
251 if (!info)
252 return 0;
253 write_lock_irqsave(&info->lock, flags);
254 bit = airq_iv_alloc(info->aiv, nvqs);
255 if (bit == -1UL) {
256
257 write_unlock_irqrestore(&info->lock, flags);
258 continue;
259 }
260 *first = bit;
261 *airq_info = info;
262 indicator_addr = (unsigned long)info->aiv->vector;
263 for (j = 0; j < nvqs; j++) {
264 airq_iv_set_ptr(info->aiv, bit + j,
265 (unsigned long)vqs[j]);
266 }
267 write_unlock_irqrestore(&info->lock, flags);
268 }
269 return indicator_addr;
270}
271
272static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
273{
274 struct virtio_ccw_vq_info *info;
275
276 list_for_each_entry(info, &vcdev->virtqueues, node)
277 drop_airq_indicator(info->vq, vcdev->airq_info);
278}
279
280static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
281{
282 unsigned long flags;
283 __u32 ret;
284
285 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
286 if (vcdev->err)
287 ret = 0;
288 else
289 ret = vcdev->curr_io & flag;
290 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
291 return ret;
292}
293
294static int ccw_io_helper(struct virtio_ccw_device *vcdev,
295 struct ccw1 *ccw, __u32 intparm)
296{
297 int ret;
298 unsigned long flags;
299 int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
300
301 do {
302 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
303 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
304 if (!ret) {
305 if (!vcdev->curr_io)
306 vcdev->err = 0;
307 vcdev->curr_io |= flag;
308 }
309 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
310 cpu_relax();
311 } while (ret == -EBUSY);
312 wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
313 return ret ? ret : vcdev->err;
314}
315
316static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
317 struct ccw1 *ccw)
318{
319 int ret;
320 unsigned long *indicatorp = NULL;
321 struct virtio_thinint_area *thinint_area = NULL;
322 struct airq_info *airq_info = vcdev->airq_info;
323
324 if (vcdev->is_thinint) {
325 thinint_area = kzalloc(sizeof(*thinint_area),
326 GFP_DMA | GFP_KERNEL);
327 if (!thinint_area)
328 return;
329 thinint_area->summary_indicator =
330 (unsigned long) &airq_info->summary_indicator;
331 thinint_area->isc = VIRTIO_AIRQ_ISC;
332 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
333 ccw->count = sizeof(*thinint_area);
334 ccw->cda = (__u32)(unsigned long) thinint_area;
335 } else {
336
337 indicatorp = kmalloc(sizeof(&vcdev->indicators),
338 GFP_DMA | GFP_KERNEL);
339 if (!indicatorp)
340 return;
341 *indicatorp = 0;
342 ccw->cmd_code = CCW_CMD_SET_IND;
343 ccw->count = sizeof(&vcdev->indicators);
344 ccw->cda = (__u32)(unsigned long) indicatorp;
345 }
346
347 vcdev->indicators = 0;
348 ccw->flags = 0;
349 ret = ccw_io_helper(vcdev, ccw,
350 vcdev->is_thinint ?
351 VIRTIO_CCW_DOING_SET_IND_ADAPTER :
352 VIRTIO_CCW_DOING_SET_IND);
353 if (ret && (ret != -ENODEV))
354 dev_info(&vcdev->cdev->dev,
355 "Failed to deregister indicators (%d)\n", ret);
356 else if (vcdev->is_thinint)
357 virtio_ccw_drop_indicators(vcdev);
358 kfree(indicatorp);
359 kfree(thinint_area);
360}
361
362static inline long do_kvm_notify(struct subchannel_id schid,
363 unsigned long queue_index,
364 long cookie)
365{
366 register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
367 register struct subchannel_id __schid asm("2") = schid;
368 register unsigned long __index asm("3") = queue_index;
369 register long __rc asm("2");
370 register long __cookie asm("4") = cookie;
371
372 asm volatile ("diag 2,4,0x500\n"
373 : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
374 "d"(__cookie)
375 : "memory", "cc");
376 return __rc;
377}
378
379static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
380{
381 struct virtio_ccw_vq_info *info = vq->priv;
382 struct virtio_ccw_device *vcdev;
383 struct subchannel_id schid;
384
385 vcdev = to_vc_device(info->vq->vdev);
386 ccw_device_get_schid(vcdev->cdev, &schid);
387 info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
388 if (info->cookie < 0)
389 return false;
390 return true;
391}
392
393static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
394 struct ccw1 *ccw, int index)
395{
396 int ret;
397
398 vcdev->config_block->index = index;
399 ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
400 ccw->flags = 0;
401 ccw->count = sizeof(struct vq_config_block);
402 ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
403 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
404 if (ret)
405 return ret;
406 return vcdev->config_block->num;
407}
408
409static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
410{
411 struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
412 struct virtio_ccw_vq_info *info = vq->priv;
413 unsigned long flags;
414 unsigned long size;
415 int ret;
416 unsigned int index = vq->index;
417
418
419 spin_lock_irqsave(&vcdev->lock, flags);
420 list_del(&info->node);
421 spin_unlock_irqrestore(&vcdev->lock, flags);
422
423
424 if (vcdev->revision == 0) {
425 info->info_block->l.queue = 0;
426 info->info_block->l.align = 0;
427 info->info_block->l.index = index;
428 info->info_block->l.num = 0;
429 ccw->count = sizeof(info->info_block->l);
430 } else {
431 info->info_block->s.desc = 0;
432 info->info_block->s.index = index;
433 info->info_block->s.num = 0;
434 info->info_block->s.avail = 0;
435 info->info_block->s.used = 0;
436 ccw->count = sizeof(info->info_block->s);
437 }
438 ccw->cmd_code = CCW_CMD_SET_VQ;
439 ccw->flags = 0;
440 ccw->cda = (__u32)(unsigned long)(info->info_block);
441 ret = ccw_io_helper(vcdev, ccw,
442 VIRTIO_CCW_DOING_SET_VQ | index);
443
444
445
446
447 if (ret && (ret != -ENODEV))
448 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
449 ret, index);
450
451 vring_del_virtqueue(vq);
452 size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
453 free_pages_exact(info->queue, size);
454 kfree(info->info_block);
455 kfree(info);
456}
457
458static void virtio_ccw_del_vqs(struct virtio_device *vdev)
459{
460 struct virtqueue *vq, *n;
461 struct ccw1 *ccw;
462 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
463
464 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
465 if (!ccw)
466 return;
467
468 virtio_ccw_drop_indicator(vcdev, ccw);
469
470 list_for_each_entry_safe(vq, n, &vdev->vqs, list)
471 virtio_ccw_del_vq(vq, ccw);
472
473 kfree(ccw);
474}
475
476static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
477 int i, vq_callback_t *callback,
478 const char *name,
479 struct ccw1 *ccw)
480{
481 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
482 int err;
483 struct virtqueue *vq = NULL;
484 struct virtio_ccw_vq_info *info;
485 unsigned long size = 0;
486 unsigned long flags;
487
488
489 info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
490 if (!info) {
491 dev_warn(&vcdev->cdev->dev, "no info\n");
492 err = -ENOMEM;
493 goto out_err;
494 }
495 info->info_block = kzalloc(sizeof(*info->info_block),
496 GFP_DMA | GFP_KERNEL);
497 if (!info->info_block) {
498 dev_warn(&vcdev->cdev->dev, "no info block\n");
499 err = -ENOMEM;
500 goto out_err;
501 }
502 info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
503 if (info->num < 0) {
504 err = info->num;
505 goto out_err;
506 }
507 size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
508 info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
509 if (info->queue == NULL) {
510 dev_warn(&vcdev->cdev->dev, "no queue\n");
511 err = -ENOMEM;
512 goto out_err;
513 }
514
515 vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
516 true, info->queue, virtio_ccw_kvm_notify,
517 callback, name);
518 if (!vq) {
519
520 dev_warn(&vcdev->cdev->dev, "no vq\n");
521 err = -ENOMEM;
522 goto out_err;
523 }
524
525
526 if (vcdev->revision == 0) {
527 info->info_block->l.queue = (__u64)info->queue;
528 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
529 info->info_block->l.index = i;
530 info->info_block->l.num = info->num;
531 ccw->count = sizeof(info->info_block->l);
532 } else {
533 info->info_block->s.desc = (__u64)info->queue;
534 info->info_block->s.index = i;
535 info->info_block->s.num = info->num;
536 info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
537 info->info_block->s.used = (__u64)virtqueue_get_used(vq);
538 ccw->count = sizeof(info->info_block->s);
539 }
540 ccw->cmd_code = CCW_CMD_SET_VQ;
541 ccw->flags = 0;
542 ccw->cda = (__u32)(unsigned long)(info->info_block);
543 err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
544 if (err) {
545 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
546 goto out_err;
547 }
548
549 info->vq = vq;
550 vq->priv = info;
551
552
553 spin_lock_irqsave(&vcdev->lock, flags);
554 list_add(&info->node, &vcdev->virtqueues);
555 spin_unlock_irqrestore(&vcdev->lock, flags);
556
557 return vq;
558
559out_err:
560 if (vq)
561 vring_del_virtqueue(vq);
562 if (info) {
563 if (info->queue)
564 free_pages_exact(info->queue, size);
565 kfree(info->info_block);
566 }
567 kfree(info);
568 return ERR_PTR(err);
569}
570
571static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
572 struct virtqueue *vqs[], int nvqs,
573 struct ccw1 *ccw)
574{
575 int ret;
576 struct virtio_thinint_area *thinint_area = NULL;
577 struct airq_info *info;
578
579 thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
580 if (!thinint_area) {
581 ret = -ENOMEM;
582 goto out;
583 }
584
585 thinint_area->indicator = get_airq_indicator(vqs, nvqs,
586 &thinint_area->bit_nr,
587 &vcdev->airq_info);
588 if (!thinint_area->indicator) {
589 ret = -ENOSPC;
590 goto out;
591 }
592 info = vcdev->airq_info;
593 thinint_area->summary_indicator =
594 (unsigned long) &info->summary_indicator;
595 thinint_area->isc = VIRTIO_AIRQ_ISC;
596 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
597 ccw->flags = CCW_FLAG_SLI;
598 ccw->count = sizeof(*thinint_area);
599 ccw->cda = (__u32)(unsigned long)thinint_area;
600 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
601 if (ret) {
602 if (ret == -EOPNOTSUPP) {
603
604
605
606
607 virtio_ccw_use_airq = 0;
608 pr_info("Adapter interrupts unsupported on host\n");
609 } else
610 dev_warn(&vcdev->cdev->dev,
611 "enabling adapter interrupts = %d\n", ret);
612 virtio_ccw_drop_indicators(vcdev);
613 }
614out:
615 kfree(thinint_area);
616 return ret;
617}
618
619static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
620 struct virtqueue *vqs[],
621 vq_callback_t *callbacks[],
622 const char * const names[])
623{
624 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
625 unsigned long *indicatorp = NULL;
626 int ret, i;
627 struct ccw1 *ccw;
628
629 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
630 if (!ccw)
631 return -ENOMEM;
632
633 for (i = 0; i < nvqs; ++i) {
634 vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
635 ccw);
636 if (IS_ERR(vqs[i])) {
637 ret = PTR_ERR(vqs[i]);
638 vqs[i] = NULL;
639 goto out;
640 }
641 }
642 ret = -ENOMEM;
643
644
645
646
647 indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
648 if (!indicatorp)
649 goto out;
650 *indicatorp = (unsigned long) &vcdev->indicators;
651 if (vcdev->is_thinint) {
652 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
653 if (ret)
654
655 vcdev->is_thinint = 0;
656 }
657 if (!vcdev->is_thinint) {
658
659 vcdev->indicators = 0;
660 ccw->cmd_code = CCW_CMD_SET_IND;
661 ccw->flags = 0;
662 ccw->count = sizeof(&vcdev->indicators);
663 ccw->cda = (__u32)(unsigned long) indicatorp;
664 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
665 if (ret)
666 goto out;
667 }
668
669 *indicatorp = (unsigned long) &vcdev->indicators2;
670 vcdev->indicators2 = 0;
671 ccw->cmd_code = CCW_CMD_SET_CONF_IND;
672 ccw->flags = 0;
673 ccw->count = sizeof(&vcdev->indicators2);
674 ccw->cda = (__u32)(unsigned long) indicatorp;
675 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
676 if (ret)
677 goto out;
678
679 kfree(indicatorp);
680 kfree(ccw);
681 return 0;
682out:
683 kfree(indicatorp);
684 kfree(ccw);
685 virtio_ccw_del_vqs(vdev);
686 return ret;
687}
688
689static void virtio_ccw_reset(struct virtio_device *vdev)
690{
691 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
692 struct ccw1 *ccw;
693
694 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
695 if (!ccw)
696 return;
697
698
699 *vcdev->status = 0;
700
701
702 ccw->cmd_code = CCW_CMD_VDEV_RESET;
703 ccw->flags = 0;
704 ccw->count = 0;
705 ccw->cda = 0;
706 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
707 kfree(ccw);
708}
709
710static u64 virtio_ccw_get_features(struct virtio_device *vdev)
711{
712 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
713 struct virtio_feature_desc *features;
714 int ret;
715 u64 rc;
716 struct ccw1 *ccw;
717
718 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
719 if (!ccw)
720 return 0;
721
722 features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
723 if (!features) {
724 rc = 0;
725 goto out_free;
726 }
727
728 features->index = 0;
729 ccw->cmd_code = CCW_CMD_READ_FEAT;
730 ccw->flags = 0;
731 ccw->count = sizeof(*features);
732 ccw->cda = (__u32)(unsigned long)features;
733 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
734 if (ret) {
735 rc = 0;
736 goto out_free;
737 }
738
739 rc = le32_to_cpu(features->features);
740
741 if (vcdev->revision == 0)
742 goto out_free;
743
744
745 features->index = 1;
746 ccw->cmd_code = CCW_CMD_READ_FEAT;
747 ccw->flags = 0;
748 ccw->count = sizeof(*features);
749 ccw->cda = (__u32)(unsigned long)features;
750 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
751 if (ret == 0)
752 rc |= (u64)le32_to_cpu(features->features) << 32;
753
754out_free:
755 kfree(features);
756 kfree(ccw);
757 return rc;
758}
759
760static int virtio_ccw_finalize_features(struct virtio_device *vdev)
761{
762 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
763 struct virtio_feature_desc *features;
764 struct ccw1 *ccw;
765 int ret;
766
767 if (vcdev->revision >= 1 &&
768 !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
769 dev_err(&vdev->dev, "virtio: device uses revision 1 "
770 "but does not have VIRTIO_F_VERSION_1\n");
771 return -EINVAL;
772 }
773
774 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
775 if (!ccw)
776 return -ENOMEM;
777
778 features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
779 if (!features) {
780 ret = -ENOMEM;
781 goto out_free;
782 }
783
784 vring_transport_features(vdev);
785
786 features->index = 0;
787 features->features = cpu_to_le32((u32)vdev->features);
788
789 ccw->cmd_code = CCW_CMD_WRITE_FEAT;
790 ccw->flags = 0;
791 ccw->count = sizeof(*features);
792 ccw->cda = (__u32)(unsigned long)features;
793 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
794 if (ret)
795 goto out_free;
796
797 if (vcdev->revision == 0)
798 goto out_free;
799
800 features->index = 1;
801 features->features = cpu_to_le32(vdev->features >> 32);
802
803 ccw->cmd_code = CCW_CMD_WRITE_FEAT;
804 ccw->flags = 0;
805 ccw->count = sizeof(*features);
806 ccw->cda = (__u32)(unsigned long)features;
807 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
808
809out_free:
810 kfree(features);
811 kfree(ccw);
812
813 return ret;
814}
815
816static void virtio_ccw_get_config(struct virtio_device *vdev,
817 unsigned int offset, void *buf, unsigned len)
818{
819 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
820 int ret;
821 struct ccw1 *ccw;
822 void *config_area;
823
824 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
825 if (!ccw)
826 return;
827
828 config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
829 if (!config_area)
830 goto out_free;
831
832
833 ccw->cmd_code = CCW_CMD_READ_CONF;
834 ccw->flags = 0;
835 ccw->count = offset + len;
836 ccw->cda = (__u32)(unsigned long)config_area;
837 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
838 if (ret)
839 goto out_free;
840
841 memcpy(vcdev->config, config_area, offset + len);
842 if (buf)
843 memcpy(buf, &vcdev->config[offset], len);
844 if (vcdev->config_ready < offset + len)
845 vcdev->config_ready = offset + len;
846
847out_free:
848 kfree(config_area);
849 kfree(ccw);
850}
851
852static void virtio_ccw_set_config(struct virtio_device *vdev,
853 unsigned int offset, const void *buf,
854 unsigned len)
855{
856 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
857 struct ccw1 *ccw;
858 void *config_area;
859
860 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
861 if (!ccw)
862 return;
863
864 config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
865 if (!config_area)
866 goto out_free;
867
868
869 if (vcdev->config_ready < offset)
870 virtio_ccw_get_config(vdev, 0, NULL, offset);
871 memcpy(&vcdev->config[offset], buf, len);
872
873 memcpy(config_area, vcdev->config, sizeof(vcdev->config));
874 ccw->cmd_code = CCW_CMD_WRITE_CONF;
875 ccw->flags = 0;
876 ccw->count = offset + len;
877 ccw->cda = (__u32)(unsigned long)config_area;
878 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
879
880out_free:
881 kfree(config_area);
882 kfree(ccw);
883}
884
885static u8 virtio_ccw_get_status(struct virtio_device *vdev)
886{
887 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
888 u8 old_status = *vcdev->status;
889 struct ccw1 *ccw;
890
891 if (vcdev->revision < 1)
892 return *vcdev->status;
893
894 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
895 if (!ccw)
896 return old_status;
897
898 ccw->cmd_code = CCW_CMD_READ_STATUS;
899 ccw->flags = 0;
900 ccw->count = sizeof(*vcdev->status);
901 ccw->cda = (__u32)(unsigned long)vcdev->status;
902 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
903
904
905
906
907
908
909 kfree(ccw);
910
911 return *vcdev->status;
912}
913
914static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
915{
916 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
917 u8 old_status = *vcdev->status;
918 struct ccw1 *ccw;
919 int ret;
920
921 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
922 if (!ccw)
923 return;
924
925
926 *vcdev->status = status;
927 ccw->cmd_code = CCW_CMD_WRITE_STATUS;
928 ccw->flags = 0;
929 ccw->count = sizeof(status);
930 ccw->cda = (__u32)(unsigned long)vcdev->status;
931 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
932
933 if (ret)
934 *vcdev->status = old_status;
935 kfree(ccw);
936}
937
938static const struct virtio_config_ops virtio_ccw_config_ops = {
939 .get_features = virtio_ccw_get_features,
940 .finalize_features = virtio_ccw_finalize_features,
941 .get = virtio_ccw_get_config,
942 .set = virtio_ccw_set_config,
943 .get_status = virtio_ccw_get_status,
944 .set_status = virtio_ccw_set_status,
945 .reset = virtio_ccw_reset,
946 .find_vqs = virtio_ccw_find_vqs,
947 .del_vqs = virtio_ccw_del_vqs,
948};
949
950
951
952
953
954
955static void virtio_ccw_release_dev(struct device *_d)
956{
957 struct virtio_device *dev = dev_to_virtio(_d);
958 struct virtio_ccw_device *vcdev = to_vc_device(dev);
959
960 kfree(vcdev->status);
961 kfree(vcdev->config_block);
962 kfree(vcdev);
963}
964
965static int irb_is_error(struct irb *irb)
966{
967 if (scsw_cstat(&irb->scsw) != 0)
968 return 1;
969 if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
970 return 1;
971 if (scsw_cc(&irb->scsw) != 0)
972 return 1;
973 return 0;
974}
975
976static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
977 int index)
978{
979 struct virtio_ccw_vq_info *info;
980 unsigned long flags;
981 struct virtqueue *vq;
982
983 vq = NULL;
984 spin_lock_irqsave(&vcdev->lock, flags);
985 list_for_each_entry(info, &vcdev->virtqueues, node) {
986 if (info->vq->index == index) {
987 vq = info->vq;
988 break;
989 }
990 }
991 spin_unlock_irqrestore(&vcdev->lock, flags);
992 return vq;
993}
994
995static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
996 __u32 activity)
997{
998 if (vcdev->curr_io & activity) {
999 switch (activity) {
1000 case VIRTIO_CCW_DOING_READ_FEAT:
1001 case VIRTIO_CCW_DOING_WRITE_FEAT:
1002 case VIRTIO_CCW_DOING_READ_CONFIG:
1003 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1004 case VIRTIO_CCW_DOING_WRITE_STATUS:
1005 case VIRTIO_CCW_DOING_READ_STATUS:
1006 case VIRTIO_CCW_DOING_SET_VQ:
1007 case VIRTIO_CCW_DOING_SET_IND:
1008 case VIRTIO_CCW_DOING_SET_CONF_IND:
1009 case VIRTIO_CCW_DOING_RESET:
1010 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1011 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1012 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1013 vcdev->curr_io &= ~activity;
1014 wake_up(&vcdev->wait_q);
1015 break;
1016 default:
1017
1018 dev_warn(&vcdev->cdev->dev,
1019 "Suspicious activity '%08x'\n", activity);
1020 WARN_ON(1);
1021 break;
1022 }
1023 }
1024}
1025
1026static void virtio_ccw_int_handler(struct ccw_device *cdev,
1027 unsigned long intparm,
1028 struct irb *irb)
1029{
1030 __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1031 struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1032 int i;
1033 struct virtqueue *vq;
1034
1035 if (!vcdev)
1036 return;
1037 if (IS_ERR(irb)) {
1038 vcdev->err = PTR_ERR(irb);
1039 virtio_ccw_check_activity(vcdev, activity);
1040
1041 return;
1042 }
1043
1044 if ((intparm == 0) &&
1045 (scsw_stctl(&irb->scsw) ==
1046 (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1047
1048 }
1049 if (irb_is_error(irb)) {
1050
1051 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1052 (irb->ecw[0] & SNS0_CMD_REJECT))
1053 vcdev->err = -EOPNOTSUPP;
1054 else
1055
1056 vcdev->err = -EIO;
1057 }
1058 virtio_ccw_check_activity(vcdev, activity);
1059 for_each_set_bit(i, &vcdev->indicators,
1060 sizeof(vcdev->indicators) * BITS_PER_BYTE) {
1061
1062 clear_bit(i, &vcdev->indicators);
1063 barrier();
1064 vq = virtio_ccw_vq_by_ind(vcdev, i);
1065 vring_interrupt(0, vq);
1066 }
1067 if (test_bit(0, &vcdev->indicators2)) {
1068 virtio_config_changed(&vcdev->vdev);
1069 clear_bit(0, &vcdev->indicators2);
1070 }
1071}
1072
1073
1074
1075
1076
1077#define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1078 (8*sizeof(long)))
1079static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1080
1081static char *no_auto = "";
1082
1083module_param(no_auto, charp, 0444);
1084MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1085
1086static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1087{
1088 struct ccw_dev_id id;
1089
1090 ccw_device_get_id(cdev, &id);
1091 if (test_bit(id.devno, devs_no_auto[id.ssid]))
1092 return 0;
1093 return 1;
1094}
1095
1096static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1097{
1098 struct ccw_device *cdev = data;
1099 int ret;
1100
1101 ret = ccw_device_set_online(cdev);
1102 if (ret)
1103 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1104}
1105
1106static int virtio_ccw_probe(struct ccw_device *cdev)
1107{
1108 cdev->handler = virtio_ccw_int_handler;
1109
1110 if (virtio_ccw_check_autoonline(cdev))
1111 async_schedule(virtio_ccw_auto_online, cdev);
1112 return 0;
1113}
1114
1115static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1116{
1117 unsigned long flags;
1118 struct virtio_ccw_device *vcdev;
1119
1120 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1121 vcdev = dev_get_drvdata(&cdev->dev);
1122 if (!vcdev || vcdev->going_away) {
1123 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1124 return NULL;
1125 }
1126 vcdev->going_away = true;
1127 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1128 return vcdev;
1129}
1130
1131static void virtio_ccw_remove(struct ccw_device *cdev)
1132{
1133 unsigned long flags;
1134 struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1135
1136 if (vcdev && cdev->online) {
1137 if (vcdev->device_lost)
1138 virtio_break_device(&vcdev->vdev);
1139 unregister_virtio_device(&vcdev->vdev);
1140 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1141 dev_set_drvdata(&cdev->dev, NULL);
1142 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1143 }
1144 cdev->handler = NULL;
1145}
1146
1147static int virtio_ccw_offline(struct ccw_device *cdev)
1148{
1149 unsigned long flags;
1150 struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1151
1152 if (!vcdev)
1153 return 0;
1154 if (vcdev->device_lost)
1155 virtio_break_device(&vcdev->vdev);
1156 unregister_virtio_device(&vcdev->vdev);
1157 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1158 dev_set_drvdata(&cdev->dev, NULL);
1159 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1160 return 0;
1161}
1162
1163static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1164{
1165 struct virtio_rev_info *rev;
1166 struct ccw1 *ccw;
1167 int ret;
1168
1169 ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
1170 if (!ccw)
1171 return -ENOMEM;
1172 rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
1173 if (!rev) {
1174 kfree(ccw);
1175 return -ENOMEM;
1176 }
1177
1178
1179 ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1180 ccw->flags = 0;
1181 ccw->count = sizeof(*rev);
1182 ccw->cda = (__u32)(unsigned long)rev;
1183
1184 vcdev->revision = VIRTIO_CCW_REV_MAX;
1185 do {
1186 rev->revision = vcdev->revision;
1187
1188 rev->length = 0;
1189 ret = ccw_io_helper(vcdev, ccw,
1190 VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1191 if (ret == -EOPNOTSUPP) {
1192 if (vcdev->revision == 0)
1193
1194
1195
1196
1197
1198 ret = 0;
1199 else
1200 vcdev->revision--;
1201 }
1202 } while (ret == -EOPNOTSUPP);
1203
1204 kfree(ccw);
1205 kfree(rev);
1206 return ret;
1207}
1208
1209static int virtio_ccw_online(struct ccw_device *cdev)
1210{
1211 int ret;
1212 struct virtio_ccw_device *vcdev;
1213 unsigned long flags;
1214
1215 vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1216 if (!vcdev) {
1217 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1218 ret = -ENOMEM;
1219 goto out_free;
1220 }
1221 vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1222 GFP_DMA | GFP_KERNEL);
1223 if (!vcdev->config_block) {
1224 ret = -ENOMEM;
1225 goto out_free;
1226 }
1227 vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1228 if (!vcdev->status) {
1229 ret = -ENOMEM;
1230 goto out_free;
1231 }
1232
1233 vcdev->is_thinint = virtio_ccw_use_airq;
1234
1235 vcdev->vdev.dev.parent = &cdev->dev;
1236 vcdev->vdev.dev.release = virtio_ccw_release_dev;
1237 vcdev->vdev.config = &virtio_ccw_config_ops;
1238 vcdev->cdev = cdev;
1239 init_waitqueue_head(&vcdev->wait_q);
1240 INIT_LIST_HEAD(&vcdev->virtqueues);
1241 spin_lock_init(&vcdev->lock);
1242
1243 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1244 dev_set_drvdata(&cdev->dev, vcdev);
1245 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1246 vcdev->vdev.id.vendor = cdev->id.cu_type;
1247 vcdev->vdev.id.device = cdev->id.cu_model;
1248
1249 ret = virtio_ccw_set_transport_rev(vcdev);
1250 if (ret)
1251 goto out_free;
1252
1253 ret = register_virtio_device(&vcdev->vdev);
1254 if (ret) {
1255 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1256 ret);
1257 goto out_put;
1258 }
1259 return 0;
1260out_put:
1261 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1262 dev_set_drvdata(&cdev->dev, NULL);
1263 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1264 put_device(&vcdev->vdev.dev);
1265 return ret;
1266out_free:
1267 if (vcdev) {
1268 kfree(vcdev->status);
1269 kfree(vcdev->config_block);
1270 }
1271 kfree(vcdev);
1272 return ret;
1273}
1274
1275static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1276{
1277 int rc;
1278 struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1279
1280
1281
1282
1283
1284 if (!vcdev)
1285 return NOTIFY_DONE;
1286
1287 switch (event) {
1288 case CIO_GONE:
1289 vcdev->device_lost = true;
1290 rc = NOTIFY_DONE;
1291 break;
1292 default:
1293 rc = NOTIFY_DONE;
1294 break;
1295 }
1296 return rc;
1297}
1298
1299static struct ccw_device_id virtio_ids[] = {
1300 { CCW_DEVICE(0x3832, 0) },
1301 {},
1302};
1303
1304static struct ccw_driver virtio_ccw_driver = {
1305 .driver = {
1306 .owner = THIS_MODULE,
1307 .name = "virtio_ccw",
1308 },
1309 .ids = virtio_ids,
1310 .probe = virtio_ccw_probe,
1311 .remove = virtio_ccw_remove,
1312 .set_offline = virtio_ccw_offline,
1313 .set_online = virtio_ccw_online,
1314 .notify = virtio_ccw_cio_notify,
1315 .int_class = IRQIO_VIR,
1316};
1317
1318static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1319 int max_digit, int max_val)
1320{
1321 int diff;
1322
1323 diff = 0;
1324 *val = 0;
1325
1326 while (diff <= max_digit) {
1327 int value = hex_to_bin(**cp);
1328
1329 if (value < 0)
1330 break;
1331 *val = *val * 16 + value;
1332 (*cp)++;
1333 diff++;
1334 }
1335
1336 if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1337 return 1;
1338
1339 return 0;
1340}
1341
1342static int __init parse_busid(char *str, unsigned int *cssid,
1343 unsigned int *ssid, unsigned int *devno)
1344{
1345 char *str_work;
1346 int rc, ret;
1347
1348 rc = 1;
1349
1350 if (*str == '\0')
1351 goto out;
1352
1353 str_work = str;
1354 ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1355 if (ret || (str_work[0] != '.'))
1356 goto out;
1357 str_work++;
1358 ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1359 if (ret || (str_work[0] != '.'))
1360 goto out;
1361 str_work++;
1362 ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1363 if (ret || (str_work[0] != '\0'))
1364 goto out;
1365
1366 rc = 0;
1367out:
1368 return rc;
1369}
1370
1371static void __init no_auto_parse(void)
1372{
1373 unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1374 char *parm, *str;
1375 int rc;
1376
1377 str = no_auto;
1378 while ((parm = strsep(&str, ","))) {
1379 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1380 &from_ssid, &from);
1381 if (rc)
1382 continue;
1383 if (parm != NULL) {
1384 rc = parse_busid(parm, &to_cssid,
1385 &to_ssid, &to);
1386 if ((from_ssid > to_ssid) ||
1387 ((from_ssid == to_ssid) && (from > to)))
1388 rc = -EINVAL;
1389 } else {
1390 to_cssid = from_cssid;
1391 to_ssid = from_ssid;
1392 to = from;
1393 }
1394 if (rc)
1395 continue;
1396 while ((from_ssid < to_ssid) ||
1397 ((from_ssid == to_ssid) && (from <= to))) {
1398 set_bit(from, devs_no_auto[from_ssid]);
1399 from++;
1400 if (from > __MAX_SUBCHANNEL) {
1401 from_ssid++;
1402 from = 0;
1403 }
1404 }
1405 }
1406}
1407
1408static int __init virtio_ccw_init(void)
1409{
1410
1411 no_auto_parse();
1412 return ccw_driver_register(&virtio_ccw_driver);
1413}
1414device_initcall(virtio_ccw_init);
1415
