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#include <asm/tpi.h>
37
38/*
39 * virtio related functions
40 */
41
42struct vq_config_block {
43 __u16 index;
44 __u16 num;
45} __packed;
46
47#define VIRTIO_CCW_CONFIG_SIZE 0x100
48/* same as PCI config space size, should be enough for all drivers */
49
50struct vcdev_dma_area {
51 unsigned long indicators;
52 unsigned long indicators2;
53 struct vq_config_block config_block;
54 __u8 status;
55};
56
57struct virtio_ccw_device {
58 struct virtio_device vdev;
59 __u8 config[VIRTIO_CCW_CONFIG_SIZE];
60 struct ccw_device *cdev;
61 __u32 curr_io;
62 int err;
63 unsigned int revision; /* Transport revision */
64 wait_queue_head_t wait_q;
65 spinlock_t lock;
66 rwlock_t irq_lock;
67 struct mutex io_lock; /* Serializes I/O requests */
68 struct list_head virtqueues;
69 bool is_thinint;
70 bool going_away;
71 bool device_lost;
72 unsigned int config_ready;
73 void *airq_info;
74 struct vcdev_dma_area *dma_area;
75};
76
77static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
78{
79 return &vcdev->dma_area->indicators;
80}
81
82static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
83{
84 return &vcdev->dma_area->indicators2;
85}
86
87struct vq_info_block_legacy {
88 __u64 queue;
89 __u32 align;
90 __u16 index;
91 __u16 num;
92} __packed;
93
94struct vq_info_block {
95 __u64 desc;
96 __u32 res0;
97 __u16 index;
98 __u16 num;
99 __u64 avail;
100 __u64 used;
101} __packed;
102
103struct virtio_feature_desc {
104 __le32 features;
105 __u8 index;
106} __packed;
107
108struct virtio_thinint_area {
109 unsigned long summary_indicator;
110 unsigned long indicator;
111 u64 bit_nr;
112 u8 isc;
113} __packed;
114
115struct virtio_rev_info {
116 __u16 revision;
117 __u16 length;
118 __u8 data[];
119};
120
121/* the highest virtio-ccw revision we support */
122#define VIRTIO_CCW_REV_MAX 2
123
124struct virtio_ccw_vq_info {
125 struct virtqueue *vq;
126 int num;
127 union {
128 struct vq_info_block s;
129 struct vq_info_block_legacy l;
130 } *info_block;
131 int bit_nr;
132 struct list_head node;
133 long cookie;
134};
135
136#define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
137
138#define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
139#define MAX_AIRQ_AREAS 20
140
141static int virtio_ccw_use_airq = 1;
142
143struct airq_info {
144 rwlock_t lock;
145 u8 summary_indicator_idx;
146 struct airq_struct airq;
147 struct airq_iv *aiv;
148};
149static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
150static DEFINE_MUTEX(airq_areas_lock);
151
152static u8 *summary_indicators;
153
154static inline u8 *get_summary_indicator(struct airq_info *info)
155{
156 return summary_indicators + info->summary_indicator_idx;
157}
158
159#define CCW_CMD_SET_VQ 0x13
160#define CCW_CMD_VDEV_RESET 0x33
161#define CCW_CMD_SET_IND 0x43
162#define CCW_CMD_SET_CONF_IND 0x53
163#define CCW_CMD_READ_FEAT 0x12
164#define CCW_CMD_WRITE_FEAT 0x11
165#define CCW_CMD_READ_CONF 0x22
166#define CCW_CMD_WRITE_CONF 0x21
167#define CCW_CMD_WRITE_STATUS 0x31
168#define CCW_CMD_READ_VQ_CONF 0x32
169#define CCW_CMD_READ_STATUS 0x72
170#define CCW_CMD_SET_IND_ADAPTER 0x73
171#define CCW_CMD_SET_VIRTIO_REV 0x83
172
173#define VIRTIO_CCW_DOING_SET_VQ 0x00010000
174#define VIRTIO_CCW_DOING_RESET 0x00040000
175#define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
176#define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
177#define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
178#define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
179#define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
180#define VIRTIO_CCW_DOING_SET_IND 0x01000000
181#define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
182#define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
183#define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
184#define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
185#define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
186#define VIRTIO_CCW_INTPARM_MASK 0xffff0000
187
188static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
189{
190 return container_of(vdev, struct virtio_ccw_device, vdev);
191}
192
193static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
194{
195 unsigned long i, flags;
196
197 write_lock_irqsave(&info->lock, flags);
198 for (i = 0; i < airq_iv_end(info->aiv); i++) {
199 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
200 airq_iv_free_bit(info->aiv, i);
201 airq_iv_set_ptr(info->aiv, i, 0);
202 break;
203 }
204 }
205 write_unlock_irqrestore(&info->lock, flags);
206}
207
208static void virtio_airq_handler(struct airq_struct *airq,
209 struct tpi_info *tpi_info)
210{
211 struct airq_info *info = container_of(airq, struct airq_info, airq);
212 unsigned long ai;
213
214 inc_irq_stat(IRQIO_VAI);
215 read_lock(&info->lock);
216 /* Walk through indicators field, summary indicator active. */
217 for (ai = 0;;) {
218 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
219 if (ai == -1UL)
220 break;
221 vring_interrupt(irq: 0, vq: (void *)airq_iv_get_ptr(info->aiv, ai));
222 }
223 *(get_summary_indicator(info)) = 0;
224 smp_wmb();
225 /* Walk through indicators field, summary indicator not active. */
226 for (ai = 0;;) {
227 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
228 if (ai == -1UL)
229 break;
230 vring_interrupt(irq: 0, vq: (void *)airq_iv_get_ptr(info->aiv, ai));
231 }
232 read_unlock(&info->lock);
233}
234
235static struct airq_info *new_airq_info(int index)
236{
237 struct airq_info *info;
238 int rc;
239
240 info = kzalloc(size: sizeof(*info), GFP_KERNEL);
241 if (!info)
242 return NULL;
243 rwlock_init(&info->lock);
244 info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
245 | AIRQ_IV_CACHELINE, NULL);
246 if (!info->aiv) {
247 kfree(objp: info);
248 return NULL;
249 }
250 info->airq.handler = virtio_airq_handler;
251 info->summary_indicator_idx = index;
252 info->airq.lsi_ptr = get_summary_indicator(info);
253 info->airq.isc = VIRTIO_AIRQ_ISC;
254 rc = register_adapter_interrupt(&info->airq);
255 if (rc) {
256 airq_iv_release(info->aiv);
257 kfree(objp: info);
258 return NULL;
259 }
260 return info;
261}
262
263static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
264 u64 *first, void **airq_info)
265{
266 int i, j;
267 struct airq_info *info;
268 unsigned long indicator_addr = 0;
269 unsigned long bit, flags;
270
271 for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
272 mutex_lock(&airq_areas_lock);
273 if (!airq_areas[i])
274 airq_areas[i] = new_airq_info(index: i);
275 info = airq_areas[i];
276 mutex_unlock(lock: &airq_areas_lock);
277 if (!info)
278 return 0;
279 write_lock_irqsave(&info->lock, flags);
280 bit = airq_iv_alloc(info->aiv, nvqs);
281 if (bit == -1UL) {
282 /* Not enough vacancies. */
283 write_unlock_irqrestore(&info->lock, flags);
284 continue;
285 }
286 *first = bit;
287 *airq_info = info;
288 indicator_addr = (unsigned long)info->aiv->vector;
289 for (j = 0; j < nvqs; j++) {
290 airq_iv_set_ptr(info->aiv, bit + j,
291 (unsigned long)vqs[j]);
292 }
293 write_unlock_irqrestore(&info->lock, flags);
294 }
295 return indicator_addr;
296}
297
298static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
299{
300 struct virtio_ccw_vq_info *info;
301
302 if (!vcdev->airq_info)
303 return;
304 list_for_each_entry(info, &vcdev->virtqueues, node)
305 drop_airq_indicator(vq: info->vq, info: vcdev->airq_info);
306}
307
308static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
309{
310 unsigned long flags;
311 __u32 ret;
312
313 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
314 if (vcdev->err)
315 ret = 0;
316 else
317 ret = vcdev->curr_io & flag;
318 spin_unlock_irqrestore(lock: get_ccwdev_lock(vcdev->cdev), flags);
319 return ret;
320}
321
322static int ccw_io_helper(struct virtio_ccw_device *vcdev,
323 struct ccw1 *ccw, __u32 intparm)
324{
325 int ret;
326 unsigned long flags;
327 int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
328
329 mutex_lock(&vcdev->io_lock);
330 do {
331 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
332 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
333 if (!ret) {
334 if (!vcdev->curr_io)
335 vcdev->err = 0;
336 vcdev->curr_io |= flag;
337 }
338 spin_unlock_irqrestore(lock: get_ccwdev_lock(vcdev->cdev), flags);
339 cpu_relax();
340 } while (ret == -EBUSY);
341 wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
342 ret = ret ? ret : vcdev->err;
343 mutex_unlock(lock: &vcdev->io_lock);
344 return ret;
345}
346
347static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
348 struct ccw1 *ccw)
349{
350 int ret;
351 unsigned long *indicatorp = NULL;
352 struct virtio_thinint_area *thinint_area = NULL;
353 struct airq_info *airq_info = vcdev->airq_info;
354
355 if (vcdev->is_thinint) {
356 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
357 sizeof(*thinint_area));
358 if (!thinint_area)
359 return;
360 thinint_area->summary_indicator =
361 (unsigned long) get_summary_indicator(info: airq_info);
362 thinint_area->isc = VIRTIO_AIRQ_ISC;
363 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
364 ccw->count = sizeof(*thinint_area);
365 ccw->cda = (__u32)virt_to_phys(address: thinint_area);
366 } else {
367 /* payload is the address of the indicators */
368 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
369 sizeof(indicators(vcdev)));
370 if (!indicatorp)
371 return;
372 *indicatorp = 0;
373 ccw->cmd_code = CCW_CMD_SET_IND;
374 ccw->count = sizeof(indicators(vcdev));
375 ccw->cda = (__u32)virt_to_phys(address: indicatorp);
376 }
377 /* Deregister indicators from host. */
378 *indicators(vcdev) = 0;
379 ccw->flags = 0;
380 ret = ccw_io_helper(vcdev, ccw,
381 intparm: vcdev->is_thinint ?
382 VIRTIO_CCW_DOING_SET_IND_ADAPTER :
383 VIRTIO_CCW_DOING_SET_IND);
384 if (ret && (ret != -ENODEV))
385 dev_info(&vcdev->cdev->dev,
386 "Failed to deregister indicators (%d)\n", ret);
387 else if (vcdev->is_thinint)
388 virtio_ccw_drop_indicators(vcdev);
389 ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev)));
390 ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
391}
392
393static inline bool virtio_ccw_do_kvm_notify(struct virtqueue *vq, u32 data)
394{
395 struct virtio_ccw_vq_info *info = vq->priv;
396 struct virtio_ccw_device *vcdev;
397 struct subchannel_id schid;
398
399 vcdev = to_vc_device(vdev: info->vq->vdev);
400 ccw_device_get_schid(vcdev->cdev, &schid);
401 BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
402 info->cookie = kvm_hypercall3(nr: KVM_S390_VIRTIO_CCW_NOTIFY,
403 p1: *((unsigned int *)&schid),
404 p2: data, p3: info->cookie);
405 if (info->cookie < 0)
406 return false;
407 return true;
408}
409
410static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
411{
412 return virtio_ccw_do_kvm_notify(vq, data: vq->index);
413}
414
415static bool virtio_ccw_kvm_notify_with_data(struct virtqueue *vq)
416{
417 return virtio_ccw_do_kvm_notify(vq, data: vring_notification_data(vq: vq));
418}
419
420static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
421 struct ccw1 *ccw, int index)
422{
423 int ret;
424
425 vcdev->dma_area->config_block.index = index;
426 ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
427 ccw->flags = 0;
428 ccw->count = sizeof(struct vq_config_block);
429 ccw->cda = (__u32)virt_to_phys(address: &vcdev->dma_area->config_block);
430 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
431 if (ret)
432 return ret;
433 return vcdev->dma_area->config_block.num ?: -ENOENT;
434}
435
436static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
437{
438 struct virtio_ccw_device *vcdev = to_vc_device(vdev: vq->vdev);
439 struct virtio_ccw_vq_info *info = vq->priv;
440 unsigned long flags;
441 int ret;
442 unsigned int index = vq->index;
443
444 /* Remove from our list. */
445 spin_lock_irqsave(&vcdev->lock, flags);
446 list_del(entry: &info->node);
447 spin_unlock_irqrestore(lock: &vcdev->lock, flags);
448
449 /* Release from host. */
450 if (vcdev->revision == 0) {
451 info->info_block->l.queue = 0;
452 info->info_block->l.align = 0;
453 info->info_block->l.index = index;
454 info->info_block->l.num = 0;
455 ccw->count = sizeof(info->info_block->l);
456 } else {
457 info->info_block->s.desc = 0;
458 info->info_block->s.index = index;
459 info->info_block->s.num = 0;
460 info->info_block->s.avail = 0;
461 info->info_block->s.used = 0;
462 ccw->count = sizeof(info->info_block->s);
463 }
464 ccw->cmd_code = CCW_CMD_SET_VQ;
465 ccw->flags = 0;
466 ccw->cda = (__u32)virt_to_phys(address: info->info_block);
467 ret = ccw_io_helper(vcdev, ccw,
468 VIRTIO_CCW_DOING_SET_VQ | index);
469 /*
470 * -ENODEV isn't considered an error: The device is gone anyway.
471 * This may happen on device detach.
472 */
473 if (ret && (ret != -ENODEV))
474 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
475 ret, index);
476
477 vring_del_virtqueue(vq);
478 ccw_device_dma_free(vcdev->cdev, info->info_block,
479 sizeof(*info->info_block));
480 kfree(objp: info);
481}
482
483static void virtio_ccw_del_vqs(struct virtio_device *vdev)
484{
485 struct virtqueue *vq, *n;
486 struct ccw1 *ccw;
487 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
488
489 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
490 if (!ccw)
491 return;
492
493 virtio_ccw_drop_indicator(vcdev, ccw);
494
495 list_for_each_entry_safe(vq, n, &vdev->vqs, list)
496 virtio_ccw_del_vq(vq, ccw);
497
498 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
499}
500
501static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
502 int i, vq_callback_t *callback,
503 const char *name, bool ctx,
504 struct ccw1 *ccw)
505{
506 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
507 bool (*notify)(struct virtqueue *vq);
508 int err;
509 struct virtqueue *vq = NULL;
510 struct virtio_ccw_vq_info *info;
511 u64 queue;
512 unsigned long flags;
513 bool may_reduce;
514
515 if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA))
516 notify = virtio_ccw_kvm_notify_with_data;
517 else
518 notify = virtio_ccw_kvm_notify;
519
520 /* Allocate queue. */
521 info = kzalloc(size: sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
522 if (!info) {
523 dev_warn(&vcdev->cdev->dev, "no info\n");
524 err = -ENOMEM;
525 goto out_err;
526 }
527 info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
528 sizeof(*info->info_block));
529 if (!info->info_block) {
530 dev_warn(&vcdev->cdev->dev, "no info block\n");
531 err = -ENOMEM;
532 goto out_err;
533 }
534 info->num = virtio_ccw_read_vq_conf(vcdev, ccw, index: i);
535 if (info->num < 0) {
536 err = info->num;
537 goto out_err;
538 }
539 may_reduce = vcdev->revision > 0;
540 vq = vring_create_virtqueue(index: i, num: info->num, vring_align: KVM_VIRTIO_CCW_RING_ALIGN,
541 vdev, weak_barriers: true, may_reduce_num: may_reduce, ctx,
542 notify, callback, name);
543
544 if (!vq) {
545 /* For now, we fail if we can't get the requested size. */
546 dev_warn(&vcdev->cdev->dev, "no vq\n");
547 err = -ENOMEM;
548 goto out_err;
549 }
550
551 vq->num_max = info->num;
552
553 /* it may have been reduced */
554 info->num = virtqueue_get_vring_size(vq);
555
556 /* Register it with the host. */
557 queue = virtqueue_get_desc_addr(vq);
558 if (vcdev->revision == 0) {
559 info->info_block->l.queue = queue;
560 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
561 info->info_block->l.index = i;
562 info->info_block->l.num = info->num;
563 ccw->count = sizeof(info->info_block->l);
564 } else {
565 info->info_block->s.desc = queue;
566 info->info_block->s.index = i;
567 info->info_block->s.num = info->num;
568 info->info_block->s.avail = (__u64)virtqueue_get_avail_addr(vq);
569 info->info_block->s.used = (__u64)virtqueue_get_used_addr(vq);
570 ccw->count = sizeof(info->info_block->s);
571 }
572 ccw->cmd_code = CCW_CMD_SET_VQ;
573 ccw->flags = 0;
574 ccw->cda = (__u32)virt_to_phys(address: info->info_block);
575 err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
576 if (err) {
577 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
578 goto out_err;
579 }
580
581 info->vq = vq;
582 vq->priv = info;
583
584 /* Save it to our list. */
585 spin_lock_irqsave(&vcdev->lock, flags);
586 list_add(new: &info->node, head: &vcdev->virtqueues);
587 spin_unlock_irqrestore(lock: &vcdev->lock, flags);
588
589 return vq;
590
591out_err:
592 if (vq)
593 vring_del_virtqueue(vq);
594 if (info) {
595 ccw_device_dma_free(vcdev->cdev, info->info_block,
596 sizeof(*info->info_block));
597 }
598 kfree(objp: info);
599 return ERR_PTR(error: err);
600}
601
602static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
603 struct virtqueue *vqs[], int nvqs,
604 struct ccw1 *ccw)
605{
606 int ret;
607 struct virtio_thinint_area *thinint_area = NULL;
608 unsigned long indicator_addr;
609 struct airq_info *info;
610
611 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
612 sizeof(*thinint_area));
613 if (!thinint_area) {
614 ret = -ENOMEM;
615 goto out;
616 }
617 /* Try to get an indicator. */
618 indicator_addr = get_airq_indicator(vqs, nvqs,
619 first: &thinint_area->bit_nr,
620 airq_info: &vcdev->airq_info);
621 if (!indicator_addr) {
622 ret = -ENOSPC;
623 goto out;
624 }
625 thinint_area->indicator = virt_to_phys(address: (void *)indicator_addr);
626 info = vcdev->airq_info;
627 thinint_area->summary_indicator =
628 virt_to_phys(address: get_summary_indicator(info));
629 thinint_area->isc = VIRTIO_AIRQ_ISC;
630 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
631 ccw->flags = CCW_FLAG_SLI;
632 ccw->count = sizeof(*thinint_area);
633 ccw->cda = (__u32)virt_to_phys(address: thinint_area);
634 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
635 if (ret) {
636 if (ret == -EOPNOTSUPP) {
637 /*
638 * The host does not support adapter interrupts
639 * for virtio-ccw, stop trying.
640 */
641 virtio_ccw_use_airq = 0;
642 pr_info("Adapter interrupts unsupported on host\n");
643 } else
644 dev_warn(&vcdev->cdev->dev,
645 "enabling adapter interrupts = %d\n", ret);
646 virtio_ccw_drop_indicators(vcdev);
647 }
648out:
649 ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
650 return ret;
651}
652
653static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
654 struct virtqueue *vqs[],
655 vq_callback_t *callbacks[],
656 const char * const names[],
657 const bool *ctx,
658 struct irq_affinity *desc)
659{
660 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
661 unsigned long *indicatorp = NULL;
662 int ret, i, queue_idx = 0;
663 struct ccw1 *ccw;
664
665 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
666 if (!ccw)
667 return -ENOMEM;
668
669 for (i = 0; i < nvqs; ++i) {
670 if (!names[i]) {
671 vqs[i] = NULL;
672 continue;
673 }
674
675 vqs[i] = virtio_ccw_setup_vq(vdev, i: queue_idx++, callback: callbacks[i],
676 name: names[i], ctx: ctx ? ctx[i] : false,
677 ccw);
678 if (IS_ERR(ptr: vqs[i])) {
679 ret = PTR_ERR(ptr: vqs[i]);
680 vqs[i] = NULL;
681 goto out;
682 }
683 }
684 ret = -ENOMEM;
685 /*
686 * We need a data area under 2G to communicate. Our payload is
687 * the address of the indicators.
688 */
689 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
690 sizeof(indicators(vcdev)));
691 if (!indicatorp)
692 goto out;
693 *indicatorp = (unsigned long) indicators(vcdev);
694 if (vcdev->is_thinint) {
695 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
696 if (ret)
697 /* no error, just fall back to legacy interrupts */
698 vcdev->is_thinint = false;
699 }
700 if (!vcdev->is_thinint) {
701 /* Register queue indicators with host. */
702 *indicators(vcdev) = 0;
703 ccw->cmd_code = CCW_CMD_SET_IND;
704 ccw->flags = 0;
705 ccw->count = sizeof(indicators(vcdev));
706 ccw->cda = (__u32)virt_to_phys(address: indicatorp);
707 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
708 if (ret)
709 goto out;
710 }
711 /* Register indicators2 with host for config changes */
712 *indicatorp = (unsigned long) indicators2(vcdev);
713 *indicators2(vcdev) = 0;
714 ccw->cmd_code = CCW_CMD_SET_CONF_IND;
715 ccw->flags = 0;
716 ccw->count = sizeof(indicators2(vcdev));
717 ccw->cda = (__u32)virt_to_phys(address: indicatorp);
718 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
719 if (ret)
720 goto out;
721
722 if (indicatorp)
723 ccw_device_dma_free(vcdev->cdev, indicatorp,
724 sizeof(indicators(vcdev)));
725 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
726 return 0;
727out:
728 if (indicatorp)
729 ccw_device_dma_free(vcdev->cdev, indicatorp,
730 sizeof(indicators(vcdev)));
731 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
732 virtio_ccw_del_vqs(vdev);
733 return ret;
734}
735
736static void virtio_ccw_reset(struct virtio_device *vdev)
737{
738 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
739 struct ccw1 *ccw;
740
741 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
742 if (!ccw)
743 return;
744
745 /* Zero status bits. */
746 vcdev->dma_area->status = 0;
747
748 /* Send a reset ccw on device. */
749 ccw->cmd_code = CCW_CMD_VDEV_RESET;
750 ccw->flags = 0;
751 ccw->count = 0;
752 ccw->cda = 0;
753 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
754 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
755}
756
757static u64 virtio_ccw_get_features(struct virtio_device *vdev)
758{
759 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
760 struct virtio_feature_desc *features;
761 int ret;
762 u64 rc;
763 struct ccw1 *ccw;
764
765 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
766 if (!ccw)
767 return 0;
768
769 features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
770 if (!features) {
771 rc = 0;
772 goto out_free;
773 }
774 /* Read the feature bits from the host. */
775 features->index = 0;
776 ccw->cmd_code = CCW_CMD_READ_FEAT;
777 ccw->flags = 0;
778 ccw->count = sizeof(*features);
779 ccw->cda = (__u32)virt_to_phys(address: features);
780 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
781 if (ret) {
782 rc = 0;
783 goto out_free;
784 }
785
786 rc = le32_to_cpu(features->features);
787
788 if (vcdev->revision == 0)
789 goto out_free;
790
791 /* Read second half of the feature bits from the host. */
792 features->index = 1;
793 ccw->cmd_code = CCW_CMD_READ_FEAT;
794 ccw->flags = 0;
795 ccw->count = sizeof(*features);
796 ccw->cda = (__u32)virt_to_phys(address: features);
797 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
798 if (ret == 0)
799 rc |= (u64)le32_to_cpu(features->features) << 32;
800
801out_free:
802 ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
803 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
804 return rc;
805}
806
807static void ccw_transport_features(struct virtio_device *vdev)
808{
809 /*
810 * Currently nothing to do here.
811 */
812}
813
814static int virtio_ccw_finalize_features(struct virtio_device *vdev)
815{
816 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
817 struct virtio_feature_desc *features;
818 struct ccw1 *ccw;
819 int ret;
820
821 if (vcdev->revision >= 1 &&
822 !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
823 dev_err(&vdev->dev, "virtio: device uses revision 1 "
824 "but does not have VIRTIO_F_VERSION_1\n");
825 return -EINVAL;
826 }
827
828 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
829 if (!ccw)
830 return -ENOMEM;
831
832 features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
833 if (!features) {
834 ret = -ENOMEM;
835 goto out_free;
836 }
837 /* Give virtio_ring a chance to accept features. */
838 vring_transport_features(vdev);
839
840 /* Give virtio_ccw a chance to accept features. */
841 ccw_transport_features(vdev);
842
843 features->index = 0;
844 features->features = cpu_to_le32((u32)vdev->features);
845 /* Write the first half of the feature bits to the host. */
846 ccw->cmd_code = CCW_CMD_WRITE_FEAT;
847 ccw->flags = 0;
848 ccw->count = sizeof(*features);
849 ccw->cda = (__u32)virt_to_phys(address: features);
850 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
851 if (ret)
852 goto out_free;
853
854 if (vcdev->revision == 0)
855 goto out_free;
856
857 features->index = 1;
858 features->features = cpu_to_le32(vdev->features >> 32);
859 /* Write the second half of the feature bits to the host. */
860 ccw->cmd_code = CCW_CMD_WRITE_FEAT;
861 ccw->flags = 0;
862 ccw->count = sizeof(*features);
863 ccw->cda = (__u32)virt_to_phys(address: features);
864 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
865
866out_free:
867 ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
868 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
869
870 return ret;
871}
872
873static void virtio_ccw_get_config(struct virtio_device *vdev,
874 unsigned int offset, void *buf, unsigned len)
875{
876 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
877 int ret;
878 struct ccw1 *ccw;
879 void *config_area;
880 unsigned long flags;
881
882 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
883 if (!ccw)
884 return;
885
886 config_area = ccw_device_dma_zalloc(vcdev->cdev,
887 VIRTIO_CCW_CONFIG_SIZE);
888 if (!config_area)
889 goto out_free;
890
891 /* Read the config area from the host. */
892 ccw->cmd_code = CCW_CMD_READ_CONF;
893 ccw->flags = 0;
894 ccw->count = offset + len;
895 ccw->cda = (__u32)virt_to_phys(address: config_area);
896 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
897 if (ret)
898 goto out_free;
899
900 spin_lock_irqsave(&vcdev->lock, flags);
901 memcpy(vcdev->config, config_area, offset + len);
902 if (vcdev->config_ready < offset + len)
903 vcdev->config_ready = offset + len;
904 spin_unlock_irqrestore(lock: &vcdev->lock, flags);
905 if (buf)
906 memcpy(buf, config_area + offset, len);
907
908out_free:
909 ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
910 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
911}
912
913static void virtio_ccw_set_config(struct virtio_device *vdev,
914 unsigned int offset, const void *buf,
915 unsigned len)
916{
917 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
918 struct ccw1 *ccw;
919 void *config_area;
920 unsigned long flags;
921
922 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
923 if (!ccw)
924 return;
925
926 config_area = ccw_device_dma_zalloc(vcdev->cdev,
927 VIRTIO_CCW_CONFIG_SIZE);
928 if (!config_area)
929 goto out_free;
930
931 /* Make sure we don't overwrite fields. */
932 if (vcdev->config_ready < offset)
933 virtio_ccw_get_config(vdev, offset: 0, NULL, len: offset);
934 spin_lock_irqsave(&vcdev->lock, flags);
935 memcpy(&vcdev->config[offset], buf, len);
936 /* Write the config area to the host. */
937 memcpy(config_area, vcdev->config, sizeof(vcdev->config));
938 spin_unlock_irqrestore(lock: &vcdev->lock, flags);
939 ccw->cmd_code = CCW_CMD_WRITE_CONF;
940 ccw->flags = 0;
941 ccw->count = offset + len;
942 ccw->cda = (__u32)virt_to_phys(address: config_area);
943 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
944
945out_free:
946 ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
947 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
948}
949
950static u8 virtio_ccw_get_status(struct virtio_device *vdev)
951{
952 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
953 u8 old_status = vcdev->dma_area->status;
954 struct ccw1 *ccw;
955
956 if (vcdev->revision < 2)
957 return vcdev->dma_area->status;
958
959 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
960 if (!ccw)
961 return old_status;
962
963 ccw->cmd_code = CCW_CMD_READ_STATUS;
964 ccw->flags = 0;
965 ccw->count = sizeof(vcdev->dma_area->status);
966 ccw->cda = (__u32)virt_to_phys(address: &vcdev->dma_area->status);
967 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
968/*
969 * If the channel program failed (should only happen if the device
970 * was hotunplugged, and then we clean up via the machine check
971 * handler anyway), vcdev->dma_area->status was not overwritten and we just
972 * return the old status, which is fine.
973*/
974 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
975
976 return vcdev->dma_area->status;
977}
978
979static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
980{
981 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
982 u8 old_status = vcdev->dma_area->status;
983 struct ccw1 *ccw;
984 int ret;
985
986 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
987 if (!ccw)
988 return;
989
990 /* Write the status to the host. */
991 vcdev->dma_area->status = status;
992 ccw->cmd_code = CCW_CMD_WRITE_STATUS;
993 ccw->flags = 0;
994 ccw->count = sizeof(status);
995 ccw->cda = (__u32)virt_to_phys(address: &vcdev->dma_area->status);
996 /* We use ssch for setting the status which is a serializing
997 * instruction that guarantees the memory writes have
998 * completed before ssch.
999 */
1000 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
1001 /* Write failed? We assume status is unchanged. */
1002 if (ret)
1003 vcdev->dma_area->status = old_status;
1004 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1005}
1006
1007static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
1008{
1009 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1010
1011 return dev_name(dev: &vcdev->cdev->dev);
1012}
1013
1014static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
1015{
1016 struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1017 struct airq_info *info = vcdev->airq_info;
1018
1019 if (info) {
1020 /*
1021 * This device uses adapter interrupts: synchronize with
1022 * vring_interrupt() called by virtio_airq_handler()
1023 * via the indicator area lock.
1024 */
1025 write_lock_irq(&info->lock);
1026 write_unlock_irq(&info->lock);
1027 } else {
1028 /* This device uses classic interrupts: synchronize
1029 * with vring_interrupt() called by
1030 * virtio_ccw_int_handler() via the per-device
1031 * irq_lock
1032 */
1033 write_lock_irq(&vcdev->irq_lock);
1034 write_unlock_irq(&vcdev->irq_lock);
1035 }
1036}
1037
1038static const struct virtio_config_ops virtio_ccw_config_ops = {
1039 .get_features = virtio_ccw_get_features,
1040 .finalize_features = virtio_ccw_finalize_features,
1041 .get = virtio_ccw_get_config,
1042 .set = virtio_ccw_set_config,
1043 .get_status = virtio_ccw_get_status,
1044 .set_status = virtio_ccw_set_status,
1045 .reset = virtio_ccw_reset,
1046 .find_vqs = virtio_ccw_find_vqs,
1047 .del_vqs = virtio_ccw_del_vqs,
1048 .bus_name = virtio_ccw_bus_name,
1049 .synchronize_cbs = virtio_ccw_synchronize_cbs,
1050};
1051
1052
1053/*
1054 * ccw bus driver related functions
1055 */
1056
1057static void virtio_ccw_release_dev(struct device *_d)
1058{
1059 struct virtio_device *dev = dev_to_virtio(_d);
1060 struct virtio_ccw_device *vcdev = to_vc_device(vdev: dev);
1061
1062 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1063 sizeof(*vcdev->dma_area));
1064 kfree(objp: vcdev);
1065}
1066
1067static int irb_is_error(struct irb *irb)
1068{
1069 if (scsw_cstat(&irb->scsw) != 0)
1070 return 1;
1071 if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1072 return 1;
1073 if (scsw_cc(&irb->scsw) != 0)
1074 return 1;
1075 return 0;
1076}
1077
1078static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1079 int index)
1080{
1081 struct virtio_ccw_vq_info *info;
1082 unsigned long flags;
1083 struct virtqueue *vq;
1084
1085 vq = NULL;
1086 spin_lock_irqsave(&vcdev->lock, flags);
1087 list_for_each_entry(info, &vcdev->virtqueues, node) {
1088 if (info->vq->index == index) {
1089 vq = info->vq;
1090 break;
1091 }
1092 }
1093 spin_unlock_irqrestore(lock: &vcdev->lock, flags);
1094 return vq;
1095}
1096
1097static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1098 __u32 activity)
1099{
1100 if (vcdev->curr_io & activity) {
1101 switch (activity) {
1102 case VIRTIO_CCW_DOING_READ_FEAT:
1103 case VIRTIO_CCW_DOING_WRITE_FEAT:
1104 case VIRTIO_CCW_DOING_READ_CONFIG:
1105 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1106 case VIRTIO_CCW_DOING_WRITE_STATUS:
1107 case VIRTIO_CCW_DOING_READ_STATUS:
1108 case VIRTIO_CCW_DOING_SET_VQ:
1109 case VIRTIO_CCW_DOING_SET_IND:
1110 case VIRTIO_CCW_DOING_SET_CONF_IND:
1111 case VIRTIO_CCW_DOING_RESET:
1112 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1113 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1114 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1115 vcdev->curr_io &= ~activity;
1116 wake_up(&vcdev->wait_q);
1117 break;
1118 default:
1119 /* don't know what to do... */
1120 dev_warn(&vcdev->cdev->dev,
1121 "Suspicious activity '%08x'\n", activity);
1122 WARN_ON(1);
1123 break;
1124 }
1125 }
1126}
1127
1128static void virtio_ccw_int_handler(struct ccw_device *cdev,
1129 unsigned long intparm,
1130 struct irb *irb)
1131{
1132 __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1133 struct virtio_ccw_device *vcdev = dev_get_drvdata(dev: &cdev->dev);
1134 int i;
1135 struct virtqueue *vq;
1136
1137 if (!vcdev)
1138 return;
1139 if (IS_ERR(ptr: irb)) {
1140 vcdev->err = PTR_ERR(ptr: irb);
1141 virtio_ccw_check_activity(vcdev, activity);
1142 /* Don't poke around indicators, something's wrong. */
1143 return;
1144 }
1145 /* Check if it's a notification from the host. */
1146 if ((intparm == 0) &&
1147 (scsw_stctl(&irb->scsw) ==
1148 (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1149 /* OK */
1150 }
1151 if (irb_is_error(irb)) {
1152 /* Command reject? */
1153 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1154 (irb->ecw[0] & SNS0_CMD_REJECT))
1155 vcdev->err = -EOPNOTSUPP;
1156 else
1157 /* Map everything else to -EIO. */
1158 vcdev->err = -EIO;
1159 }
1160 virtio_ccw_check_activity(vcdev, activity);
1161#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1162 /*
1163 * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1164 * disabled here.
1165 */
1166 read_lock(&vcdev->irq_lock);
1167#endif
1168 for_each_set_bit(i, indicators(vcdev),
1169 sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1170 /* The bit clear must happen before the vring kick. */
1171 clear_bit(nr: i, addr: indicators(vcdev));
1172 barrier();
1173 vq = virtio_ccw_vq_by_ind(vcdev, index: i);
1174 vring_interrupt(irq: 0, vq: vq);
1175 }
1176#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1177 read_unlock(&vcdev->irq_lock);
1178#endif
1179 if (test_bit(0, indicators2(vcdev))) {
1180 virtio_config_changed(dev: &vcdev->vdev);
1181 clear_bit(nr: 0, addr: indicators2(vcdev));
1182 }
1183}
1184
1185/*
1186 * We usually want to autoonline all devices, but give the admin
1187 * a way to exempt devices from this.
1188 */
1189#define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1190 (8*sizeof(long)))
1191static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1192
1193static char *no_auto = "";
1194
1195module_param(no_auto, charp, 0444);
1196MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1197
1198static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1199{
1200 struct ccw_dev_id id;
1201
1202 ccw_device_get_id(cdev, &id);
1203 if (test_bit(id.devno, devs_no_auto[id.ssid]))
1204 return 0;
1205 return 1;
1206}
1207
1208static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1209{
1210 struct ccw_device *cdev = data;
1211 int ret;
1212
1213 ret = ccw_device_set_online(cdev);
1214 if (ret)
1215 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1216}
1217
1218static int virtio_ccw_probe(struct ccw_device *cdev)
1219{
1220 cdev->handler = virtio_ccw_int_handler;
1221
1222 if (virtio_ccw_check_autoonline(cdev))
1223 async_schedule(func: virtio_ccw_auto_online, data: cdev);
1224 return 0;
1225}
1226
1227static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1228{
1229 unsigned long flags;
1230 struct virtio_ccw_device *vcdev;
1231
1232 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1233 vcdev = dev_get_drvdata(dev: &cdev->dev);
1234 if (!vcdev || vcdev->going_away) {
1235 spin_unlock_irqrestore(lock: get_ccwdev_lock(cdev), flags);
1236 return NULL;
1237 }
1238 vcdev->going_away = true;
1239 spin_unlock_irqrestore(lock: get_ccwdev_lock(cdev), flags);
1240 return vcdev;
1241}
1242
1243static void virtio_ccw_remove(struct ccw_device *cdev)
1244{
1245 unsigned long flags;
1246 struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1247
1248 if (vcdev && cdev->online) {
1249 if (vcdev->device_lost)
1250 virtio_break_device(dev: &vcdev->vdev);
1251 unregister_virtio_device(dev: &vcdev->vdev);
1252 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1253 dev_set_drvdata(dev: &cdev->dev, NULL);
1254 spin_unlock_irqrestore(lock: get_ccwdev_lock(cdev), flags);
1255 }
1256 cdev->handler = NULL;
1257}
1258
1259static int virtio_ccw_offline(struct ccw_device *cdev)
1260{
1261 unsigned long flags;
1262 struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1263
1264 if (!vcdev)
1265 return 0;
1266 if (vcdev->device_lost)
1267 virtio_break_device(dev: &vcdev->vdev);
1268 unregister_virtio_device(dev: &vcdev->vdev);
1269 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1270 dev_set_drvdata(dev: &cdev->dev, NULL);
1271 spin_unlock_irqrestore(lock: get_ccwdev_lock(cdev), flags);
1272 return 0;
1273}
1274
1275static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1276{
1277 struct virtio_rev_info *rev;
1278 struct ccw1 *ccw;
1279 int ret;
1280
1281 ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1282 if (!ccw)
1283 return -ENOMEM;
1284 rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1285 if (!rev) {
1286 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1287 return -ENOMEM;
1288 }
1289
1290 /* Set transport revision */
1291 ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1292 ccw->flags = 0;
1293 ccw->count = sizeof(*rev);
1294 ccw->cda = (__u32)virt_to_phys(address: rev);
1295
1296 vcdev->revision = VIRTIO_CCW_REV_MAX;
1297 do {
1298 rev->revision = vcdev->revision;
1299 /* none of our supported revisions carry payload */
1300 rev->length = 0;
1301 ret = ccw_io_helper(vcdev, ccw,
1302 VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1303 if (ret == -EOPNOTSUPP) {
1304 if (vcdev->revision == 0)
1305 /*
1306 * The host device does not support setting
1307 * the revision: let's operate it in legacy
1308 * mode.
1309 */
1310 ret = 0;
1311 else
1312 vcdev->revision--;
1313 }
1314 } while (ret == -EOPNOTSUPP);
1315
1316 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1317 ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1318 return ret;
1319}
1320
1321static int virtio_ccw_online(struct ccw_device *cdev)
1322{
1323 int ret;
1324 struct virtio_ccw_device *vcdev;
1325 unsigned long flags;
1326
1327 vcdev = kzalloc(size: sizeof(*vcdev), GFP_KERNEL);
1328 if (!vcdev) {
1329 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1330 ret = -ENOMEM;
1331 goto out_free;
1332 }
1333 vcdev->vdev.dev.parent = &cdev->dev;
1334 vcdev->cdev = cdev;
1335 vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1336 sizeof(*vcdev->dma_area));
1337 if (!vcdev->dma_area) {
1338 ret = -ENOMEM;
1339 goto out_free;
1340 }
1341
1342 vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1343
1344 vcdev->vdev.dev.release = virtio_ccw_release_dev;
1345 vcdev->vdev.config = &virtio_ccw_config_ops;
1346 init_waitqueue_head(&vcdev->wait_q);
1347 INIT_LIST_HEAD(list: &vcdev->virtqueues);
1348 spin_lock_init(&vcdev->lock);
1349 rwlock_init(&vcdev->irq_lock);
1350 mutex_init(&vcdev->io_lock);
1351
1352 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1353 dev_set_drvdata(dev: &cdev->dev, data: vcdev);
1354 spin_unlock_irqrestore(lock: get_ccwdev_lock(cdev), flags);
1355 vcdev->vdev.id.vendor = cdev->id.cu_type;
1356 vcdev->vdev.id.device = cdev->id.cu_model;
1357
1358 ret = virtio_ccw_set_transport_rev(vcdev);
1359 if (ret)
1360 goto out_free;
1361
1362 ret = register_virtio_device(dev: &vcdev->vdev);
1363 if (ret) {
1364 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1365 ret);
1366 goto out_put;
1367 }
1368 return 0;
1369out_put:
1370 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1371 dev_set_drvdata(dev: &cdev->dev, NULL);
1372 spin_unlock_irqrestore(lock: get_ccwdev_lock(cdev), flags);
1373 put_device(dev: &vcdev->vdev.dev);
1374 return ret;
1375out_free:
1376 if (vcdev) {
1377 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1378 sizeof(*vcdev->dma_area));
1379 }
1380 kfree(objp: vcdev);
1381 return ret;
1382}
1383
1384static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1385{
1386 int rc;
1387 struct virtio_ccw_device *vcdev = dev_get_drvdata(dev: &cdev->dev);
1388
1389 /*
1390 * Make sure vcdev is set
1391 * i.e. set_offline/remove callback not already running
1392 */
1393 if (!vcdev)
1394 return NOTIFY_DONE;
1395
1396 switch (event) {
1397 case CIO_GONE:
1398 vcdev->device_lost = true;
1399 rc = NOTIFY_DONE;
1400 break;
1401 case CIO_OPER:
1402 rc = NOTIFY_OK;
1403 break;
1404 default:
1405 rc = NOTIFY_DONE;
1406 break;
1407 }
1408 return rc;
1409}
1410
1411static struct ccw_device_id virtio_ids[] = {
1412 { CCW_DEVICE(0x3832, 0) },
1413 {},
1414};
1415
1416static struct ccw_driver virtio_ccw_driver = {
1417 .driver = {
1418 .owner = THIS_MODULE,
1419 .name = "virtio_ccw",
1420 },
1421 .ids = virtio_ids,
1422 .probe = virtio_ccw_probe,
1423 .remove = virtio_ccw_remove,
1424 .set_offline = virtio_ccw_offline,
1425 .set_online = virtio_ccw_online,
1426 .notify = virtio_ccw_cio_notify,
1427 .int_class = IRQIO_VIR,
1428};
1429
1430static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1431 int max_digit, int max_val)
1432{
1433 int diff;
1434
1435 diff = 0;
1436 *val = 0;
1437
1438 while (diff <= max_digit) {
1439 int value = hex_to_bin(ch: **cp);
1440
1441 if (value < 0)
1442 break;
1443 *val = *val * 16 + value;
1444 (*cp)++;
1445 diff++;
1446 }
1447
1448 if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1449 return 1;
1450
1451 return 0;
1452}
1453
1454static int __init parse_busid(char *str, unsigned int *cssid,
1455 unsigned int *ssid, unsigned int *devno)
1456{
1457 char *str_work;
1458 int rc, ret;
1459
1460 rc = 1;
1461
1462 if (*str == '\0')
1463 goto out;
1464
1465 str_work = str;
1466 ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1467 if (ret || (str_work[0] != '.'))
1468 goto out;
1469 str_work++;
1470 ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1471 if (ret || (str_work[0] != '.'))
1472 goto out;
1473 str_work++;
1474 ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1475 if (ret || (str_work[0] != '\0'))
1476 goto out;
1477
1478 rc = 0;
1479out:
1480 return rc;
1481}
1482
1483static void __init no_auto_parse(void)
1484{
1485 unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1486 char *parm, *str;
1487 int rc;
1488
1489 str = no_auto;
1490 while ((parm = strsep(&str, ","))) {
1491 rc = parse_busid(str: strsep(&parm, "-"), cssid: &from_cssid,
1492 ssid: &from_ssid, devno: &from);
1493 if (rc)
1494 continue;
1495 if (parm != NULL) {
1496 rc = parse_busid(str: parm, cssid: &to_cssid,
1497 ssid: &to_ssid, devno: &to);
1498 if ((from_ssid > to_ssid) ||
1499 ((from_ssid == to_ssid) && (from > to)))
1500 rc = -EINVAL;
1501 } else {
1502 to_cssid = from_cssid;
1503 to_ssid = from_ssid;
1504 to = from;
1505 }
1506 if (rc)
1507 continue;
1508 while ((from_ssid < to_ssid) ||
1509 ((from_ssid == to_ssid) && (from <= to))) {
1510 set_bit(nr: from, addr: devs_no_auto[from_ssid]);
1511 from++;
1512 if (from > __MAX_SUBCHANNEL) {
1513 from_ssid++;
1514 from = 0;
1515 }
1516 }
1517 }
1518}
1519
1520static int __init virtio_ccw_init(void)
1521{
1522 int rc;
1523
1524 /* parse no_auto string before we do anything further */
1525 no_auto_parse();
1526
1527 summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1528 if (!summary_indicators)
1529 return -ENOMEM;
1530 rc = ccw_driver_register(&virtio_ccw_driver);
1531 if (rc)
1532 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1533 return rc;
1534}
1535device_initcall(virtio_ccw_init);
1536

source code of linux/drivers/s390/virtio/virtio_ccw.c