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