xref: /openbmc/linux/drivers/s390/virtio/virtio_ccw.c (revision 71844fac)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ccw based virtio transport
4  *
5  * Copyright IBM Corp. 2012, 2014
6  *
7  *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
8  */
9 
10 #include <linux/kernel_stat.h>
11 #include <linux/init.h>
12 #include <linux/memblock.h>
13 #include <linux/err.h>
14 #include <linux/virtio.h>
15 #include <linux/virtio_config.h>
16 #include <linux/slab.h>
17 #include <linux/interrupt.h>
18 #include <linux/virtio_ring.h>
19 #include <linux/pfn.h>
20 #include <linux/async.h>
21 #include <linux/wait.h>
22 #include <linux/list.h>
23 #include <linux/bitops.h>
24 #include <linux/moduleparam.h>
25 #include <linux/io.h>
26 #include <linux/kvm_para.h>
27 #include <linux/notifier.h>
28 #include <asm/diag.h>
29 #include <asm/setup.h>
30 #include <asm/irq.h>
31 #include <asm/cio.h>
32 #include <asm/ccwdev.h>
33 #include <asm/virtio-ccw.h>
34 #include <asm/isc.h>
35 #include <asm/airq.h>
36 
37 /*
38  * virtio related functions
39  */
40 
41 struct vq_config_block {
42 	__u16 index;
43 	__u16 num;
44 } __packed;
45 
46 #define VIRTIO_CCW_CONFIG_SIZE 0x100
47 /* same as PCI config space size, should be enough for all drivers */
48 
49 struct virtio_ccw_device {
50 	struct virtio_device vdev;
51 	__u8 *status;
52 	__u8 config[VIRTIO_CCW_CONFIG_SIZE];
53 	struct ccw_device *cdev;
54 	__u32 curr_io;
55 	int err;
56 	unsigned int revision; /* Transport revision */
57 	wait_queue_head_t wait_q;
58 	spinlock_t lock;
59 	struct list_head virtqueues;
60 	unsigned long indicators;
61 	unsigned long indicators2;
62 	struct vq_config_block *config_block;
63 	bool is_thinint;
64 	bool going_away;
65 	bool device_lost;
66 	unsigned int config_ready;
67 	void *airq_info;
68 };
69 
70 struct vq_info_block_legacy {
71 	__u64 queue;
72 	__u32 align;
73 	__u16 index;
74 	__u16 num;
75 } __packed;
76 
77 struct vq_info_block {
78 	__u64 desc;
79 	__u32 res0;
80 	__u16 index;
81 	__u16 num;
82 	__u64 avail;
83 	__u64 used;
84 } __packed;
85 
86 struct virtio_feature_desc {
87 	__le32 features;
88 	__u8 index;
89 } __packed;
90 
91 struct virtio_thinint_area {
92 	unsigned long summary_indicator;
93 	unsigned long indicator;
94 	u64 bit_nr;
95 	u8 isc;
96 } __packed;
97 
98 struct virtio_rev_info {
99 	__u16 revision;
100 	__u16 length;
101 	__u8 data[];
102 };
103 
104 /* the highest virtio-ccw revision we support */
105 #define VIRTIO_CCW_REV_MAX 1
106 
107 struct virtio_ccw_vq_info {
108 	struct virtqueue *vq;
109 	int num;
110 	void *queue;
111 	union {
112 		struct vq_info_block s;
113 		struct vq_info_block_legacy l;
114 	} *info_block;
115 	int bit_nr;
116 	struct list_head node;
117 	long cookie;
118 };
119 
120 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
121 
122 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
123 #define MAX_AIRQ_AREAS 20
124 
125 static int virtio_ccw_use_airq = 1;
126 
127 struct airq_info {
128 	rwlock_t lock;
129 	u8 summary_indicator;
130 	struct airq_struct airq;
131 	struct airq_iv *aiv;
132 };
133 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
134 
135 #define CCW_CMD_SET_VQ 0x13
136 #define CCW_CMD_VDEV_RESET 0x33
137 #define CCW_CMD_SET_IND 0x43
138 #define CCW_CMD_SET_CONF_IND 0x53
139 #define CCW_CMD_READ_FEAT 0x12
140 #define CCW_CMD_WRITE_FEAT 0x11
141 #define CCW_CMD_READ_CONF 0x22
142 #define CCW_CMD_WRITE_CONF 0x21
143 #define CCW_CMD_WRITE_STATUS 0x31
144 #define CCW_CMD_READ_VQ_CONF 0x32
145 #define CCW_CMD_READ_STATUS 0x72
146 #define CCW_CMD_SET_IND_ADAPTER 0x73
147 #define CCW_CMD_SET_VIRTIO_REV 0x83
148 
149 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
150 #define VIRTIO_CCW_DOING_RESET 0x00040000
151 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
152 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
153 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
154 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
155 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
156 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
157 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
158 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
159 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
160 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
161 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
162 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
163 
164 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
165 {
166 	return container_of(vdev, struct virtio_ccw_device, vdev);
167 }
168 
169 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
170 {
171 	unsigned long i, flags;
172 
173 	write_lock_irqsave(&info->lock, flags);
174 	for (i = 0; i < airq_iv_end(info->aiv); i++) {
175 		if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
176 			airq_iv_free_bit(info->aiv, i);
177 			airq_iv_set_ptr(info->aiv, i, 0);
178 			break;
179 		}
180 	}
181 	write_unlock_irqrestore(&info->lock, flags);
182 }
183 
184 static void virtio_airq_handler(struct airq_struct *airq)
185 {
186 	struct airq_info *info = container_of(airq, struct airq_info, airq);
187 	unsigned long ai;
188 
189 	inc_irq_stat(IRQIO_VAI);
190 	read_lock(&info->lock);
191 	/* Walk through indicators field, summary indicator active. */
192 	for (ai = 0;;) {
193 		ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
194 		if (ai == -1UL)
195 			break;
196 		vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
197 	}
198 	info->summary_indicator = 0;
199 	smp_wmb();
200 	/* Walk through indicators field, summary indicator not active. */
201 	for (ai = 0;;) {
202 		ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
203 		if (ai == -1UL)
204 			break;
205 		vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
206 	}
207 	read_unlock(&info->lock);
208 }
209 
210 static struct airq_info *new_airq_info(void)
211 {
212 	struct airq_info *info;
213 	int rc;
214 
215 	info = kzalloc(sizeof(*info), GFP_KERNEL);
216 	if (!info)
217 		return NULL;
218 	rwlock_init(&info->lock);
219 	info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
220 	if (!info->aiv) {
221 		kfree(info);
222 		return NULL;
223 	}
224 	info->airq.handler = virtio_airq_handler;
225 	info->airq.lsi_ptr = &info->summary_indicator;
226 	info->airq.lsi_mask = 0xff;
227 	info->airq.isc = VIRTIO_AIRQ_ISC;
228 	rc = register_adapter_interrupt(&info->airq);
229 	if (rc) {
230 		airq_iv_release(info->aiv);
231 		kfree(info);
232 		return NULL;
233 	}
234 	return info;
235 }
236 
237 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
238 					u64 *first, void **airq_info)
239 {
240 	int i, j;
241 	struct airq_info *info;
242 	unsigned long indicator_addr = 0;
243 	unsigned long bit, flags;
244 
245 	for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
246 		if (!airq_areas[i])
247 			airq_areas[i] = new_airq_info();
248 		info = airq_areas[i];
249 		if (!info)
250 			return 0;
251 		write_lock_irqsave(&info->lock, flags);
252 		bit = airq_iv_alloc(info->aiv, nvqs);
253 		if (bit == -1UL) {
254 			/* Not enough vacancies. */
255 			write_unlock_irqrestore(&info->lock, flags);
256 			continue;
257 		}
258 		*first = bit;
259 		*airq_info = info;
260 		indicator_addr = (unsigned long)info->aiv->vector;
261 		for (j = 0; j < nvqs; j++) {
262 			airq_iv_set_ptr(info->aiv, bit + j,
263 					(unsigned long)vqs[j]);
264 		}
265 		write_unlock_irqrestore(&info->lock, flags);
266 	}
267 	return indicator_addr;
268 }
269 
270 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
271 {
272 	struct virtio_ccw_vq_info *info;
273 
274 	list_for_each_entry(info, &vcdev->virtqueues, node)
275 		drop_airq_indicator(info->vq, vcdev->airq_info);
276 }
277 
278 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
279 {
280 	unsigned long flags;
281 	__u32 ret;
282 
283 	spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
284 	if (vcdev->err)
285 		ret = 0;
286 	else
287 		ret = vcdev->curr_io & flag;
288 	spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
289 	return ret;
290 }
291 
292 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
293 			 struct ccw1 *ccw, __u32 intparm)
294 {
295 	int ret;
296 	unsigned long flags;
297 	int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
298 
299 	do {
300 		spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
301 		ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
302 		if (!ret) {
303 			if (!vcdev->curr_io)
304 				vcdev->err = 0;
305 			vcdev->curr_io |= flag;
306 		}
307 		spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
308 		cpu_relax();
309 	} while (ret == -EBUSY);
310 	wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
311 	return ret ? ret : vcdev->err;
312 }
313 
314 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
315 				      struct ccw1 *ccw)
316 {
317 	int ret;
318 	unsigned long *indicatorp = NULL;
319 	struct virtio_thinint_area *thinint_area = NULL;
320 	struct airq_info *airq_info = vcdev->airq_info;
321 
322 	if (vcdev->is_thinint) {
323 		thinint_area = kzalloc(sizeof(*thinint_area),
324 				       GFP_DMA | GFP_KERNEL);
325 		if (!thinint_area)
326 			return;
327 		thinint_area->summary_indicator =
328 			(unsigned long) &airq_info->summary_indicator;
329 		thinint_area->isc = VIRTIO_AIRQ_ISC;
330 		ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
331 		ccw->count = sizeof(*thinint_area);
332 		ccw->cda = (__u32)(unsigned long) thinint_area;
333 	} else {
334 		/* payload is the address of the indicators */
335 		indicatorp = kmalloc(sizeof(&vcdev->indicators),
336 				     GFP_DMA | GFP_KERNEL);
337 		if (!indicatorp)
338 			return;
339 		*indicatorp = 0;
340 		ccw->cmd_code = CCW_CMD_SET_IND;
341 		ccw->count = sizeof(&vcdev->indicators);
342 		ccw->cda = (__u32)(unsigned long) indicatorp;
343 	}
344 	/* Deregister indicators from host. */
345 	vcdev->indicators = 0;
346 	ccw->flags = 0;
347 	ret = ccw_io_helper(vcdev, ccw,
348 			    vcdev->is_thinint ?
349 			    VIRTIO_CCW_DOING_SET_IND_ADAPTER :
350 			    VIRTIO_CCW_DOING_SET_IND);
351 	if (ret && (ret != -ENODEV))
352 		dev_info(&vcdev->cdev->dev,
353 			 "Failed to deregister indicators (%d)\n", ret);
354 	else if (vcdev->is_thinint)
355 		virtio_ccw_drop_indicators(vcdev);
356 	kfree(indicatorp);
357 	kfree(thinint_area);
358 }
359 
360 static inline long __do_kvm_notify(struct subchannel_id schid,
361 				   unsigned long queue_index,
362 				   long cookie)
363 {
364 	register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
365 	register struct subchannel_id __schid asm("2") = schid;
366 	register unsigned long __index asm("3") = queue_index;
367 	register long __rc asm("2");
368 	register long __cookie asm("4") = cookie;
369 
370 	asm volatile ("diag 2,4,0x500\n"
371 		      : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
372 		      "d"(__cookie)
373 		      : "memory", "cc");
374 	return __rc;
375 }
376 
377 static inline long do_kvm_notify(struct subchannel_id schid,
378 				 unsigned long queue_index,
379 				 long cookie)
380 {
381 	diag_stat_inc(DIAG_STAT_X500);
382 	return __do_kvm_notify(schid, queue_index, cookie);
383 }
384 
385 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
386 {
387 	struct virtio_ccw_vq_info *info = vq->priv;
388 	struct virtio_ccw_device *vcdev;
389 	struct subchannel_id schid;
390 
391 	vcdev = to_vc_device(info->vq->vdev);
392 	ccw_device_get_schid(vcdev->cdev, &schid);
393 	info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
394 	if (info->cookie < 0)
395 		return false;
396 	return true;
397 }
398 
399 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
400 				   struct ccw1 *ccw, int index)
401 {
402 	int ret;
403 
404 	vcdev->config_block->index = index;
405 	ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
406 	ccw->flags = 0;
407 	ccw->count = sizeof(struct vq_config_block);
408 	ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
409 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
410 	if (ret)
411 		return ret;
412 	return vcdev->config_block->num;
413 }
414 
415 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
416 {
417 	struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
418 	struct virtio_ccw_vq_info *info = vq->priv;
419 	unsigned long flags;
420 	unsigned long size;
421 	int ret;
422 	unsigned int index = vq->index;
423 
424 	/* Remove from our list. */
425 	spin_lock_irqsave(&vcdev->lock, flags);
426 	list_del(&info->node);
427 	spin_unlock_irqrestore(&vcdev->lock, flags);
428 
429 	/* Release from host. */
430 	if (vcdev->revision == 0) {
431 		info->info_block->l.queue = 0;
432 		info->info_block->l.align = 0;
433 		info->info_block->l.index = index;
434 		info->info_block->l.num = 0;
435 		ccw->count = sizeof(info->info_block->l);
436 	} else {
437 		info->info_block->s.desc = 0;
438 		info->info_block->s.index = index;
439 		info->info_block->s.num = 0;
440 		info->info_block->s.avail = 0;
441 		info->info_block->s.used = 0;
442 		ccw->count = sizeof(info->info_block->s);
443 	}
444 	ccw->cmd_code = CCW_CMD_SET_VQ;
445 	ccw->flags = 0;
446 	ccw->cda = (__u32)(unsigned long)(info->info_block);
447 	ret = ccw_io_helper(vcdev, ccw,
448 			    VIRTIO_CCW_DOING_SET_VQ | index);
449 	/*
450 	 * -ENODEV isn't considered an error: The device is gone anyway.
451 	 * This may happen on device detach.
452 	 */
453 	if (ret && (ret != -ENODEV))
454 		dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
455 			 ret, index);
456 
457 	vring_del_virtqueue(vq);
458 	size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
459 	free_pages_exact(info->queue, size);
460 	kfree(info->info_block);
461 	kfree(info);
462 }
463 
464 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
465 {
466 	struct virtqueue *vq, *n;
467 	struct ccw1 *ccw;
468 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
469 
470 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
471 	if (!ccw)
472 		return;
473 
474 	virtio_ccw_drop_indicator(vcdev, ccw);
475 
476 	list_for_each_entry_safe(vq, n, &vdev->vqs, list)
477 		virtio_ccw_del_vq(vq, ccw);
478 
479 	kfree(ccw);
480 }
481 
482 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
483 					     int i, vq_callback_t *callback,
484 					     const char *name, bool ctx,
485 					     struct ccw1 *ccw)
486 {
487 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
488 	int err;
489 	struct virtqueue *vq = NULL;
490 	struct virtio_ccw_vq_info *info;
491 	unsigned long size = 0; /* silence the compiler */
492 	unsigned long flags;
493 
494 	/* Allocate queue. */
495 	info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
496 	if (!info) {
497 		dev_warn(&vcdev->cdev->dev, "no info\n");
498 		err = -ENOMEM;
499 		goto out_err;
500 	}
501 	info->info_block = kzalloc(sizeof(*info->info_block),
502 				   GFP_DMA | GFP_KERNEL);
503 	if (!info->info_block) {
504 		dev_warn(&vcdev->cdev->dev, "no info block\n");
505 		err = -ENOMEM;
506 		goto out_err;
507 	}
508 	info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
509 	if (info->num < 0) {
510 		err = info->num;
511 		goto out_err;
512 	}
513 	size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
514 	info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
515 	if (info->queue == NULL) {
516 		dev_warn(&vcdev->cdev->dev, "no queue\n");
517 		err = -ENOMEM;
518 		goto out_err;
519 	}
520 
521 	vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
522 				 true, ctx, info->queue, virtio_ccw_kvm_notify,
523 				 callback, name);
524 	if (!vq) {
525 		/* For now, we fail if we can't get the requested size. */
526 		dev_warn(&vcdev->cdev->dev, "no vq\n");
527 		err = -ENOMEM;
528 		goto out_err;
529 	}
530 
531 	/* Register it with the host. */
532 	if (vcdev->revision == 0) {
533 		info->info_block->l.queue = (__u64)info->queue;
534 		info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
535 		info->info_block->l.index = i;
536 		info->info_block->l.num = info->num;
537 		ccw->count = sizeof(info->info_block->l);
538 	} else {
539 		info->info_block->s.desc = (__u64)info->queue;
540 		info->info_block->s.index = i;
541 		info->info_block->s.num = info->num;
542 		info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
543 		info->info_block->s.used = (__u64)virtqueue_get_used(vq);
544 		ccw->count = sizeof(info->info_block->s);
545 	}
546 	ccw->cmd_code = CCW_CMD_SET_VQ;
547 	ccw->flags = 0;
548 	ccw->cda = (__u32)(unsigned long)(info->info_block);
549 	err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
550 	if (err) {
551 		dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
552 		goto out_err;
553 	}
554 
555 	info->vq = vq;
556 	vq->priv = info;
557 
558 	/* Save it to our list. */
559 	spin_lock_irqsave(&vcdev->lock, flags);
560 	list_add(&info->node, &vcdev->virtqueues);
561 	spin_unlock_irqrestore(&vcdev->lock, flags);
562 
563 	return vq;
564 
565 out_err:
566 	if (vq)
567 		vring_del_virtqueue(vq);
568 	if (info) {
569 		if (info->queue)
570 			free_pages_exact(info->queue, size);
571 		kfree(info->info_block);
572 	}
573 	kfree(info);
574 	return ERR_PTR(err);
575 }
576 
577 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
578 					   struct virtqueue *vqs[], int nvqs,
579 					   struct ccw1 *ccw)
580 {
581 	int ret;
582 	struct virtio_thinint_area *thinint_area = NULL;
583 	struct airq_info *info;
584 
585 	thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
586 	if (!thinint_area) {
587 		ret = -ENOMEM;
588 		goto out;
589 	}
590 	/* Try to get an indicator. */
591 	thinint_area->indicator = get_airq_indicator(vqs, nvqs,
592 						     &thinint_area->bit_nr,
593 						     &vcdev->airq_info);
594 	if (!thinint_area->indicator) {
595 		ret = -ENOSPC;
596 		goto out;
597 	}
598 	info = vcdev->airq_info;
599 	thinint_area->summary_indicator =
600 		(unsigned long) &info->summary_indicator;
601 	thinint_area->isc = VIRTIO_AIRQ_ISC;
602 	ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
603 	ccw->flags = CCW_FLAG_SLI;
604 	ccw->count = sizeof(*thinint_area);
605 	ccw->cda = (__u32)(unsigned long)thinint_area;
606 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
607 	if (ret) {
608 		if (ret == -EOPNOTSUPP) {
609 			/*
610 			 * The host does not support adapter interrupts
611 			 * for virtio-ccw, stop trying.
612 			 */
613 			virtio_ccw_use_airq = 0;
614 			pr_info("Adapter interrupts unsupported on host\n");
615 		} else
616 			dev_warn(&vcdev->cdev->dev,
617 				 "enabling adapter interrupts = %d\n", ret);
618 		virtio_ccw_drop_indicators(vcdev);
619 	}
620 out:
621 	kfree(thinint_area);
622 	return ret;
623 }
624 
625 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
626 			       struct virtqueue *vqs[],
627 			       vq_callback_t *callbacks[],
628 			       const char * const names[],
629 			       const bool *ctx,
630 			       struct irq_affinity *desc)
631 {
632 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
633 	unsigned long *indicatorp = NULL;
634 	int ret, i;
635 	struct ccw1 *ccw;
636 
637 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
638 	if (!ccw)
639 		return -ENOMEM;
640 
641 	for (i = 0; i < nvqs; ++i) {
642 		vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
643 					     ctx ? ctx[i] : false, ccw);
644 		if (IS_ERR(vqs[i])) {
645 			ret = PTR_ERR(vqs[i]);
646 			vqs[i] = NULL;
647 			goto out;
648 		}
649 	}
650 	ret = -ENOMEM;
651 	/*
652 	 * We need a data area under 2G to communicate. Our payload is
653 	 * the address of the indicators.
654 	*/
655 	indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
656 	if (!indicatorp)
657 		goto out;
658 	*indicatorp = (unsigned long) &vcdev->indicators;
659 	if (vcdev->is_thinint) {
660 		ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
661 		if (ret)
662 			/* no error, just fall back to legacy interrupts */
663 			vcdev->is_thinint = false;
664 	}
665 	if (!vcdev->is_thinint) {
666 		/* Register queue indicators with host. */
667 		vcdev->indicators = 0;
668 		ccw->cmd_code = CCW_CMD_SET_IND;
669 		ccw->flags = 0;
670 		ccw->count = sizeof(&vcdev->indicators);
671 		ccw->cda = (__u32)(unsigned long) indicatorp;
672 		ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
673 		if (ret)
674 			goto out;
675 	}
676 	/* Register indicators2 with host for config changes */
677 	*indicatorp = (unsigned long) &vcdev->indicators2;
678 	vcdev->indicators2 = 0;
679 	ccw->cmd_code = CCW_CMD_SET_CONF_IND;
680 	ccw->flags = 0;
681 	ccw->count = sizeof(&vcdev->indicators2);
682 	ccw->cda = (__u32)(unsigned long) indicatorp;
683 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
684 	if (ret)
685 		goto out;
686 
687 	kfree(indicatorp);
688 	kfree(ccw);
689 	return 0;
690 out:
691 	kfree(indicatorp);
692 	kfree(ccw);
693 	virtio_ccw_del_vqs(vdev);
694 	return ret;
695 }
696 
697 static void virtio_ccw_reset(struct virtio_device *vdev)
698 {
699 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
700 	struct ccw1 *ccw;
701 
702 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
703 	if (!ccw)
704 		return;
705 
706 	/* Zero status bits. */
707 	*vcdev->status = 0;
708 
709 	/* Send a reset ccw on device. */
710 	ccw->cmd_code = CCW_CMD_VDEV_RESET;
711 	ccw->flags = 0;
712 	ccw->count = 0;
713 	ccw->cda = 0;
714 	ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
715 	kfree(ccw);
716 }
717 
718 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
719 {
720 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
721 	struct virtio_feature_desc *features;
722 	int ret;
723 	u64 rc;
724 	struct ccw1 *ccw;
725 
726 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
727 	if (!ccw)
728 		return 0;
729 
730 	features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
731 	if (!features) {
732 		rc = 0;
733 		goto out_free;
734 	}
735 	/* Read the feature bits from the host. */
736 	features->index = 0;
737 	ccw->cmd_code = CCW_CMD_READ_FEAT;
738 	ccw->flags = 0;
739 	ccw->count = sizeof(*features);
740 	ccw->cda = (__u32)(unsigned long)features;
741 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
742 	if (ret) {
743 		rc = 0;
744 		goto out_free;
745 	}
746 
747 	rc = le32_to_cpu(features->features);
748 
749 	if (vcdev->revision == 0)
750 		goto out_free;
751 
752 	/* Read second half of the feature bits from the host. */
753 	features->index = 1;
754 	ccw->cmd_code = CCW_CMD_READ_FEAT;
755 	ccw->flags = 0;
756 	ccw->count = sizeof(*features);
757 	ccw->cda = (__u32)(unsigned long)features;
758 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
759 	if (ret == 0)
760 		rc |= (u64)le32_to_cpu(features->features) << 32;
761 
762 out_free:
763 	kfree(features);
764 	kfree(ccw);
765 	return rc;
766 }
767 
768 static void ccw_transport_features(struct virtio_device *vdev)
769 {
770 	/*
771 	 * Packed ring isn't enabled on virtio_ccw for now,
772 	 * because virtio_ccw uses some legacy accessors,
773 	 * e.g. virtqueue_get_avail() and virtqueue_get_used()
774 	 * which aren't available in packed ring currently.
775 	 */
776 	__virtio_clear_bit(vdev, VIRTIO_F_RING_PACKED);
777 }
778 
779 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
780 {
781 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
782 	struct virtio_feature_desc *features;
783 	struct ccw1 *ccw;
784 	int ret;
785 
786 	if (vcdev->revision >= 1 &&
787 	    !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
788 		dev_err(&vdev->dev, "virtio: device uses revision 1 "
789 			"but does not have VIRTIO_F_VERSION_1\n");
790 		return -EINVAL;
791 	}
792 
793 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
794 	if (!ccw)
795 		return -ENOMEM;
796 
797 	features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
798 	if (!features) {
799 		ret = -ENOMEM;
800 		goto out_free;
801 	}
802 	/* Give virtio_ring a chance to accept features. */
803 	vring_transport_features(vdev);
804 
805 	/* Give virtio_ccw a chance to accept features. */
806 	ccw_transport_features(vdev);
807 
808 	features->index = 0;
809 	features->features = cpu_to_le32((u32)vdev->features);
810 	/* Write the first half of the feature bits to the host. */
811 	ccw->cmd_code = CCW_CMD_WRITE_FEAT;
812 	ccw->flags = 0;
813 	ccw->count = sizeof(*features);
814 	ccw->cda = (__u32)(unsigned long)features;
815 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
816 	if (ret)
817 		goto out_free;
818 
819 	if (vcdev->revision == 0)
820 		goto out_free;
821 
822 	features->index = 1;
823 	features->features = cpu_to_le32(vdev->features >> 32);
824 	/* Write the second half of the feature bits to the host. */
825 	ccw->cmd_code = CCW_CMD_WRITE_FEAT;
826 	ccw->flags = 0;
827 	ccw->count = sizeof(*features);
828 	ccw->cda = (__u32)(unsigned long)features;
829 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
830 
831 out_free:
832 	kfree(features);
833 	kfree(ccw);
834 
835 	return ret;
836 }
837 
838 static void virtio_ccw_get_config(struct virtio_device *vdev,
839 				  unsigned int offset, void *buf, unsigned len)
840 {
841 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
842 	int ret;
843 	struct ccw1 *ccw;
844 	void *config_area;
845 
846 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
847 	if (!ccw)
848 		return;
849 
850 	config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
851 	if (!config_area)
852 		goto out_free;
853 
854 	/* Read the config area from the host. */
855 	ccw->cmd_code = CCW_CMD_READ_CONF;
856 	ccw->flags = 0;
857 	ccw->count = offset + len;
858 	ccw->cda = (__u32)(unsigned long)config_area;
859 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
860 	if (ret)
861 		goto out_free;
862 
863 	memcpy(vcdev->config, config_area, offset + len);
864 	if (buf)
865 		memcpy(buf, &vcdev->config[offset], len);
866 	if (vcdev->config_ready < offset + len)
867 		vcdev->config_ready = offset + len;
868 
869 out_free:
870 	kfree(config_area);
871 	kfree(ccw);
872 }
873 
874 static void virtio_ccw_set_config(struct virtio_device *vdev,
875 				  unsigned int offset, const void *buf,
876 				  unsigned len)
877 {
878 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
879 	struct ccw1 *ccw;
880 	void *config_area;
881 
882 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
883 	if (!ccw)
884 		return;
885 
886 	config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
887 	if (!config_area)
888 		goto out_free;
889 
890 	/* Make sure we don't overwrite fields. */
891 	if (vcdev->config_ready < offset)
892 		virtio_ccw_get_config(vdev, 0, NULL, offset);
893 	memcpy(&vcdev->config[offset], buf, len);
894 	/* Write the config area to the host. */
895 	memcpy(config_area, vcdev->config, sizeof(vcdev->config));
896 	ccw->cmd_code = CCW_CMD_WRITE_CONF;
897 	ccw->flags = 0;
898 	ccw->count = offset + len;
899 	ccw->cda = (__u32)(unsigned long)config_area;
900 	ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
901 
902 out_free:
903 	kfree(config_area);
904 	kfree(ccw);
905 }
906 
907 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
908 {
909 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
910 	u8 old_status = *vcdev->status;
911 	struct ccw1 *ccw;
912 
913 	if (vcdev->revision < 1)
914 		return *vcdev->status;
915 
916 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
917 	if (!ccw)
918 		return old_status;
919 
920 	ccw->cmd_code = CCW_CMD_READ_STATUS;
921 	ccw->flags = 0;
922 	ccw->count = sizeof(*vcdev->status);
923 	ccw->cda = (__u32)(unsigned long)vcdev->status;
924 	ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
925 /*
926  * If the channel program failed (should only happen if the device
927  * was hotunplugged, and then we clean up via the machine check
928  * handler anyway), vcdev->status was not overwritten and we just
929  * return the old status, which is fine.
930 */
931 	kfree(ccw);
932 
933 	return *vcdev->status;
934 }
935 
936 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
937 {
938 	struct virtio_ccw_device *vcdev = to_vc_device(vdev);
939 	u8 old_status = *vcdev->status;
940 	struct ccw1 *ccw;
941 	int ret;
942 
943 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
944 	if (!ccw)
945 		return;
946 
947 	/* Write the status to the host. */
948 	*vcdev->status = status;
949 	ccw->cmd_code = CCW_CMD_WRITE_STATUS;
950 	ccw->flags = 0;
951 	ccw->count = sizeof(status);
952 	ccw->cda = (__u32)(unsigned long)vcdev->status;
953 	ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
954 	/* Write failed? We assume status is unchanged. */
955 	if (ret)
956 		*vcdev->status = old_status;
957 	kfree(ccw);
958 }
959 
960 static const struct virtio_config_ops virtio_ccw_config_ops = {
961 	.get_features = virtio_ccw_get_features,
962 	.finalize_features = virtio_ccw_finalize_features,
963 	.get = virtio_ccw_get_config,
964 	.set = virtio_ccw_set_config,
965 	.get_status = virtio_ccw_get_status,
966 	.set_status = virtio_ccw_set_status,
967 	.reset = virtio_ccw_reset,
968 	.find_vqs = virtio_ccw_find_vqs,
969 	.del_vqs = virtio_ccw_del_vqs,
970 };
971 
972 
973 /*
974  * ccw bus driver related functions
975  */
976 
977 static void virtio_ccw_release_dev(struct device *_d)
978 {
979 	struct virtio_device *dev = dev_to_virtio(_d);
980 	struct virtio_ccw_device *vcdev = to_vc_device(dev);
981 
982 	kfree(vcdev->status);
983 	kfree(vcdev->config_block);
984 	kfree(vcdev);
985 }
986 
987 static int irb_is_error(struct irb *irb)
988 {
989 	if (scsw_cstat(&irb->scsw) != 0)
990 		return 1;
991 	if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
992 		return 1;
993 	if (scsw_cc(&irb->scsw) != 0)
994 		return 1;
995 	return 0;
996 }
997 
998 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
999 					      int index)
1000 {
1001 	struct virtio_ccw_vq_info *info;
1002 	unsigned long flags;
1003 	struct virtqueue *vq;
1004 
1005 	vq = NULL;
1006 	spin_lock_irqsave(&vcdev->lock, flags);
1007 	list_for_each_entry(info, &vcdev->virtqueues, node) {
1008 		if (info->vq->index == index) {
1009 			vq = info->vq;
1010 			break;
1011 		}
1012 	}
1013 	spin_unlock_irqrestore(&vcdev->lock, flags);
1014 	return vq;
1015 }
1016 
1017 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1018 				      __u32 activity)
1019 {
1020 	if (vcdev->curr_io & activity) {
1021 		switch (activity) {
1022 		case VIRTIO_CCW_DOING_READ_FEAT:
1023 		case VIRTIO_CCW_DOING_WRITE_FEAT:
1024 		case VIRTIO_CCW_DOING_READ_CONFIG:
1025 		case VIRTIO_CCW_DOING_WRITE_CONFIG:
1026 		case VIRTIO_CCW_DOING_WRITE_STATUS:
1027 		case VIRTIO_CCW_DOING_READ_STATUS:
1028 		case VIRTIO_CCW_DOING_SET_VQ:
1029 		case VIRTIO_CCW_DOING_SET_IND:
1030 		case VIRTIO_CCW_DOING_SET_CONF_IND:
1031 		case VIRTIO_CCW_DOING_RESET:
1032 		case VIRTIO_CCW_DOING_READ_VQ_CONF:
1033 		case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1034 		case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1035 			vcdev->curr_io &= ~activity;
1036 			wake_up(&vcdev->wait_q);
1037 			break;
1038 		default:
1039 			/* don't know what to do... */
1040 			dev_warn(&vcdev->cdev->dev,
1041 				 "Suspicious activity '%08x'\n", activity);
1042 			WARN_ON(1);
1043 			break;
1044 		}
1045 	}
1046 }
1047 
1048 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1049 				   unsigned long intparm,
1050 				   struct irb *irb)
1051 {
1052 	__u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1053 	struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1054 	int i;
1055 	struct virtqueue *vq;
1056 
1057 	if (!vcdev)
1058 		return;
1059 	if (IS_ERR(irb)) {
1060 		vcdev->err = PTR_ERR(irb);
1061 		virtio_ccw_check_activity(vcdev, activity);
1062 		/* Don't poke around indicators, something's wrong. */
1063 		return;
1064 	}
1065 	/* Check if it's a notification from the host. */
1066 	if ((intparm == 0) &&
1067 	    (scsw_stctl(&irb->scsw) ==
1068 	     (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1069 		/* OK */
1070 	}
1071 	if (irb_is_error(irb)) {
1072 		/* Command reject? */
1073 		if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1074 		    (irb->ecw[0] & SNS0_CMD_REJECT))
1075 			vcdev->err = -EOPNOTSUPP;
1076 		else
1077 			/* Map everything else to -EIO. */
1078 			vcdev->err = -EIO;
1079 	}
1080 	virtio_ccw_check_activity(vcdev, activity);
1081 	for_each_set_bit(i, &vcdev->indicators,
1082 			 sizeof(vcdev->indicators) * BITS_PER_BYTE) {
1083 		/* The bit clear must happen before the vring kick. */
1084 		clear_bit(i, &vcdev->indicators);
1085 		barrier();
1086 		vq = virtio_ccw_vq_by_ind(vcdev, i);
1087 		vring_interrupt(0, vq);
1088 	}
1089 	if (test_bit(0, &vcdev->indicators2)) {
1090 		virtio_config_changed(&vcdev->vdev);
1091 		clear_bit(0, &vcdev->indicators2);
1092 	}
1093 }
1094 
1095 /*
1096  * We usually want to autoonline all devices, but give the admin
1097  * a way to exempt devices from this.
1098  */
1099 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1100 		     (8*sizeof(long)))
1101 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1102 
1103 static char *no_auto = "";
1104 
1105 module_param(no_auto, charp, 0444);
1106 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1107 
1108 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1109 {
1110 	struct ccw_dev_id id;
1111 
1112 	ccw_device_get_id(cdev, &id);
1113 	if (test_bit(id.devno, devs_no_auto[id.ssid]))
1114 		return 0;
1115 	return 1;
1116 }
1117 
1118 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1119 {
1120 	struct ccw_device *cdev = data;
1121 	int ret;
1122 
1123 	ret = ccw_device_set_online(cdev);
1124 	if (ret)
1125 		dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1126 }
1127 
1128 static int virtio_ccw_probe(struct ccw_device *cdev)
1129 {
1130 	cdev->handler = virtio_ccw_int_handler;
1131 
1132 	if (virtio_ccw_check_autoonline(cdev))
1133 		async_schedule(virtio_ccw_auto_online, cdev);
1134 	return 0;
1135 }
1136 
1137 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1138 {
1139 	unsigned long flags;
1140 	struct virtio_ccw_device *vcdev;
1141 
1142 	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1143 	vcdev = dev_get_drvdata(&cdev->dev);
1144 	if (!vcdev || vcdev->going_away) {
1145 		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1146 		return NULL;
1147 	}
1148 	vcdev->going_away = true;
1149 	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1150 	return vcdev;
1151 }
1152 
1153 static void virtio_ccw_remove(struct ccw_device *cdev)
1154 {
1155 	unsigned long flags;
1156 	struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1157 
1158 	if (vcdev && cdev->online) {
1159 		if (vcdev->device_lost)
1160 			virtio_break_device(&vcdev->vdev);
1161 		unregister_virtio_device(&vcdev->vdev);
1162 		spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1163 		dev_set_drvdata(&cdev->dev, NULL);
1164 		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1165 	}
1166 	cdev->handler = NULL;
1167 }
1168 
1169 static int virtio_ccw_offline(struct ccw_device *cdev)
1170 {
1171 	unsigned long flags;
1172 	struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1173 
1174 	if (!vcdev)
1175 		return 0;
1176 	if (vcdev->device_lost)
1177 		virtio_break_device(&vcdev->vdev);
1178 	unregister_virtio_device(&vcdev->vdev);
1179 	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1180 	dev_set_drvdata(&cdev->dev, NULL);
1181 	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1182 	return 0;
1183 }
1184 
1185 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1186 {
1187 	struct virtio_rev_info *rev;
1188 	struct ccw1 *ccw;
1189 	int ret;
1190 
1191 	ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
1192 	if (!ccw)
1193 		return -ENOMEM;
1194 	rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
1195 	if (!rev) {
1196 		kfree(ccw);
1197 		return -ENOMEM;
1198 	}
1199 
1200 	/* Set transport revision */
1201 	ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1202 	ccw->flags = 0;
1203 	ccw->count = sizeof(*rev);
1204 	ccw->cda = (__u32)(unsigned long)rev;
1205 
1206 	vcdev->revision = VIRTIO_CCW_REV_MAX;
1207 	do {
1208 		rev->revision = vcdev->revision;
1209 		/* none of our supported revisions carry payload */
1210 		rev->length = 0;
1211 		ret = ccw_io_helper(vcdev, ccw,
1212 				    VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1213 		if (ret == -EOPNOTSUPP) {
1214 			if (vcdev->revision == 0)
1215 				/*
1216 				 * The host device does not support setting
1217 				 * the revision: let's operate it in legacy
1218 				 * mode.
1219 				 */
1220 				ret = 0;
1221 			else
1222 				vcdev->revision--;
1223 		}
1224 	} while (ret == -EOPNOTSUPP);
1225 
1226 	kfree(ccw);
1227 	kfree(rev);
1228 	return ret;
1229 }
1230 
1231 static int virtio_ccw_online(struct ccw_device *cdev)
1232 {
1233 	int ret;
1234 	struct virtio_ccw_device *vcdev;
1235 	unsigned long flags;
1236 
1237 	vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1238 	if (!vcdev) {
1239 		dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1240 		ret = -ENOMEM;
1241 		goto out_free;
1242 	}
1243 	vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1244 				   GFP_DMA | GFP_KERNEL);
1245 	if (!vcdev->config_block) {
1246 		ret = -ENOMEM;
1247 		goto out_free;
1248 	}
1249 	vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1250 	if (!vcdev->status) {
1251 		ret = -ENOMEM;
1252 		goto out_free;
1253 	}
1254 
1255 	vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1256 
1257 	vcdev->vdev.dev.parent = &cdev->dev;
1258 	vcdev->vdev.dev.release = virtio_ccw_release_dev;
1259 	vcdev->vdev.config = &virtio_ccw_config_ops;
1260 	vcdev->cdev = cdev;
1261 	init_waitqueue_head(&vcdev->wait_q);
1262 	INIT_LIST_HEAD(&vcdev->virtqueues);
1263 	spin_lock_init(&vcdev->lock);
1264 
1265 	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1266 	dev_set_drvdata(&cdev->dev, vcdev);
1267 	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1268 	vcdev->vdev.id.vendor = cdev->id.cu_type;
1269 	vcdev->vdev.id.device = cdev->id.cu_model;
1270 
1271 	ret = virtio_ccw_set_transport_rev(vcdev);
1272 	if (ret)
1273 		goto out_free;
1274 
1275 	ret = register_virtio_device(&vcdev->vdev);
1276 	if (ret) {
1277 		dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1278 			 ret);
1279 		goto out_put;
1280 	}
1281 	return 0;
1282 out_put:
1283 	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1284 	dev_set_drvdata(&cdev->dev, NULL);
1285 	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1286 	put_device(&vcdev->vdev.dev);
1287 	return ret;
1288 out_free:
1289 	if (vcdev) {
1290 		kfree(vcdev->status);
1291 		kfree(vcdev->config_block);
1292 	}
1293 	kfree(vcdev);
1294 	return ret;
1295 }
1296 
1297 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1298 {
1299 	int rc;
1300 	struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1301 
1302 	/*
1303 	 * Make sure vcdev is set
1304 	 * i.e. set_offline/remove callback not already running
1305 	 */
1306 	if (!vcdev)
1307 		return NOTIFY_DONE;
1308 
1309 	switch (event) {
1310 	case CIO_GONE:
1311 		vcdev->device_lost = true;
1312 		rc = NOTIFY_DONE;
1313 		break;
1314 	case CIO_OPER:
1315 		rc = NOTIFY_OK;
1316 		break;
1317 	default:
1318 		rc = NOTIFY_DONE;
1319 		break;
1320 	}
1321 	return rc;
1322 }
1323 
1324 static struct ccw_device_id virtio_ids[] = {
1325 	{ CCW_DEVICE(0x3832, 0) },
1326 	{},
1327 };
1328 
1329 #ifdef CONFIG_PM_SLEEP
1330 static int virtio_ccw_freeze(struct ccw_device *cdev)
1331 {
1332 	struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1333 
1334 	return virtio_device_freeze(&vcdev->vdev);
1335 }
1336 
1337 static int virtio_ccw_restore(struct ccw_device *cdev)
1338 {
1339 	struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1340 	int ret;
1341 
1342 	ret = virtio_ccw_set_transport_rev(vcdev);
1343 	if (ret)
1344 		return ret;
1345 
1346 	return virtio_device_restore(&vcdev->vdev);
1347 }
1348 #endif
1349 
1350 static struct ccw_driver virtio_ccw_driver = {
1351 	.driver = {
1352 		.owner = THIS_MODULE,
1353 		.name = "virtio_ccw",
1354 	},
1355 	.ids = virtio_ids,
1356 	.probe = virtio_ccw_probe,
1357 	.remove = virtio_ccw_remove,
1358 	.set_offline = virtio_ccw_offline,
1359 	.set_online = virtio_ccw_online,
1360 	.notify = virtio_ccw_cio_notify,
1361 	.int_class = IRQIO_VIR,
1362 #ifdef CONFIG_PM_SLEEP
1363 	.freeze = virtio_ccw_freeze,
1364 	.thaw = virtio_ccw_restore,
1365 	.restore = virtio_ccw_restore,
1366 #endif
1367 };
1368 
1369 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1370 			   int max_digit, int max_val)
1371 {
1372 	int diff;
1373 
1374 	diff = 0;
1375 	*val = 0;
1376 
1377 	while (diff <= max_digit) {
1378 		int value = hex_to_bin(**cp);
1379 
1380 		if (value < 0)
1381 			break;
1382 		*val = *val * 16 + value;
1383 		(*cp)++;
1384 		diff++;
1385 	}
1386 
1387 	if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1388 		return 1;
1389 
1390 	return 0;
1391 }
1392 
1393 static int __init parse_busid(char *str, unsigned int *cssid,
1394 			      unsigned int *ssid, unsigned int *devno)
1395 {
1396 	char *str_work;
1397 	int rc, ret;
1398 
1399 	rc = 1;
1400 
1401 	if (*str == '\0')
1402 		goto out;
1403 
1404 	str_work = str;
1405 	ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1406 	if (ret || (str_work[0] != '.'))
1407 		goto out;
1408 	str_work++;
1409 	ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1410 	if (ret || (str_work[0] != '.'))
1411 		goto out;
1412 	str_work++;
1413 	ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1414 	if (ret || (str_work[0] != '\0'))
1415 		goto out;
1416 
1417 	rc = 0;
1418 out:
1419 	return rc;
1420 }
1421 
1422 static void __init no_auto_parse(void)
1423 {
1424 	unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1425 	char *parm, *str;
1426 	int rc;
1427 
1428 	str = no_auto;
1429 	while ((parm = strsep(&str, ","))) {
1430 		rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1431 				 &from_ssid, &from);
1432 		if (rc)
1433 			continue;
1434 		if (parm != NULL) {
1435 			rc = parse_busid(parm, &to_cssid,
1436 					 &to_ssid, &to);
1437 			if ((from_ssid > to_ssid) ||
1438 			    ((from_ssid == to_ssid) && (from > to)))
1439 				rc = -EINVAL;
1440 		} else {
1441 			to_cssid = from_cssid;
1442 			to_ssid = from_ssid;
1443 			to = from;
1444 		}
1445 		if (rc)
1446 			continue;
1447 		while ((from_ssid < to_ssid) ||
1448 		       ((from_ssid == to_ssid) && (from <= to))) {
1449 			set_bit(from, devs_no_auto[from_ssid]);
1450 			from++;
1451 			if (from > __MAX_SUBCHANNEL) {
1452 				from_ssid++;
1453 				from = 0;
1454 			}
1455 		}
1456 	}
1457 }
1458 
1459 static int __init virtio_ccw_init(void)
1460 {
1461 	/* parse no_auto string before we do anything further */
1462 	no_auto_parse();
1463 	return ccw_driver_register(&virtio_ccw_driver);
1464 }
1465 device_initcall(virtio_ccw_init);
1466