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[karo-tx-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         __u32 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,
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, 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 {
633         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
634         unsigned long *indicatorp = NULL;
635         int ret, i;
636         struct ccw1 *ccw;
637
638         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
639         if (!ccw)
640                 return -ENOMEM;
641
642         for (i = 0; i < nvqs; ++i) {
643                 vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
644                                              ccw);
645                 if (IS_ERR(vqs[i])) {
646                         ret = PTR_ERR(vqs[i]);
647                         vqs[i] = NULL;
648                         goto out;
649                 }
650         }
651         ret = -ENOMEM;
652         /*
653          * We need a data area under 2G to communicate. Our payload is
654          * the address of the indicators.
655         */
656         indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
657         if (!indicatorp)
658                 goto out;
659         *indicatorp = (unsigned long) &vcdev->indicators;
660         if (vcdev->is_thinint) {
661                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
662                 if (ret)
663                         /* no error, just fall back to legacy interrupts */
664                         vcdev->is_thinint = 0;
665         }
666         if (!vcdev->is_thinint) {
667                 /* Register queue indicators with host. */
668                 vcdev->indicators = 0;
669                 ccw->cmd_code = CCW_CMD_SET_IND;
670                 ccw->flags = 0;
671                 ccw->count = sizeof(&vcdev->indicators);
672                 ccw->cda = (__u32)(unsigned long) indicatorp;
673                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
674                 if (ret)
675                         goto out;
676         }
677         /* Register indicators2 with host for config changes */
678         *indicatorp = (unsigned long) &vcdev->indicators2;
679         vcdev->indicators2 = 0;
680         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
681         ccw->flags = 0;
682         ccw->count = sizeof(&vcdev->indicators2);
683         ccw->cda = (__u32)(unsigned long) indicatorp;
684         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
685         if (ret)
686                 goto out;
687
688         kfree(indicatorp);
689         kfree(ccw);
690         return 0;
691 out:
692         kfree(indicatorp);
693         kfree(ccw);
694         virtio_ccw_del_vqs(vdev);
695         return ret;
696 }
697
698 static void virtio_ccw_reset(struct virtio_device *vdev)
699 {
700         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
701         struct ccw1 *ccw;
702
703         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
704         if (!ccw)
705                 return;
706
707         /* Zero status bits. */
708         *vcdev->status = 0;
709
710         /* Send a reset ccw on device. */
711         ccw->cmd_code = CCW_CMD_VDEV_RESET;
712         ccw->flags = 0;
713         ccw->count = 0;
714         ccw->cda = 0;
715         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
716         kfree(ccw);
717 }
718
719 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
720 {
721         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
722         struct virtio_feature_desc *features;
723         int ret;
724         u64 rc;
725         struct ccw1 *ccw;
726
727         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
728         if (!ccw)
729                 return 0;
730
731         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
732         if (!features) {
733                 rc = 0;
734                 goto out_free;
735         }
736         /* Read the feature bits from the host. */
737         features->index = 0;
738         ccw->cmd_code = CCW_CMD_READ_FEAT;
739         ccw->flags = 0;
740         ccw->count = sizeof(*features);
741         ccw->cda = (__u32)(unsigned long)features;
742         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
743         if (ret) {
744                 rc = 0;
745                 goto out_free;
746         }
747
748         rc = le32_to_cpu(features->features);
749
750         if (vcdev->revision == 0)
751                 goto out_free;
752
753         /* Read second half of the feature bits from the host. */
754         features->index = 1;
755         ccw->cmd_code = CCW_CMD_READ_FEAT;
756         ccw->flags = 0;
757         ccw->count = sizeof(*features);
758         ccw->cda = (__u32)(unsigned long)features;
759         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
760         if (ret == 0)
761                 rc |= (u64)le32_to_cpu(features->features) << 32;
762
763 out_free:
764         kfree(features);
765         kfree(ccw);
766         return rc;
767 }
768
769 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
770 {
771         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
772         struct virtio_feature_desc *features;
773         struct ccw1 *ccw;
774         int ret;
775
776         if (vcdev->revision >= 1 &&
777             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
778                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
779                         "but does not have VIRTIO_F_VERSION_1\n");
780                 return -EINVAL;
781         }
782
783         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
784         if (!ccw)
785                 return -ENOMEM;
786
787         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
788         if (!features) {
789                 ret = -ENOMEM;
790                 goto out_free;
791         }
792         /* Give virtio_ring a chance to accept features. */
793         vring_transport_features(vdev);
794
795         features->index = 0;
796         features->features = cpu_to_le32((u32)vdev->features);
797         /* Write the first half of the feature bits to the host. */
798         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
799         ccw->flags = 0;
800         ccw->count = sizeof(*features);
801         ccw->cda = (__u32)(unsigned long)features;
802         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
803         if (ret)
804                 goto out_free;
805
806         if (vcdev->revision == 0)
807                 goto out_free;
808
809         features->index = 1;
810         features->features = cpu_to_le32(vdev->features >> 32);
811         /* Write the second half of the feature bits to the host. */
812         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
813         ccw->flags = 0;
814         ccw->count = sizeof(*features);
815         ccw->cda = (__u32)(unsigned long)features;
816         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
817
818 out_free:
819         kfree(features);
820         kfree(ccw);
821
822         return ret;
823 }
824
825 static void virtio_ccw_get_config(struct virtio_device *vdev,
826                                   unsigned int offset, void *buf, unsigned len)
827 {
828         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
829         int ret;
830         struct ccw1 *ccw;
831         void *config_area;
832
833         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
834         if (!ccw)
835                 return;
836
837         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
838         if (!config_area)
839                 goto out_free;
840
841         /* Read the config area from the host. */
842         ccw->cmd_code = CCW_CMD_READ_CONF;
843         ccw->flags = 0;
844         ccw->count = offset + len;
845         ccw->cda = (__u32)(unsigned long)config_area;
846         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
847         if (ret)
848                 goto out_free;
849
850         memcpy(vcdev->config, config_area, offset + len);
851         if (buf)
852                 memcpy(buf, &vcdev->config[offset], len);
853         if (vcdev->config_ready < offset + len)
854                 vcdev->config_ready = offset + len;
855
856 out_free:
857         kfree(config_area);
858         kfree(ccw);
859 }
860
861 static void virtio_ccw_set_config(struct virtio_device *vdev,
862                                   unsigned int offset, const void *buf,
863                                   unsigned len)
864 {
865         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
866         struct ccw1 *ccw;
867         void *config_area;
868
869         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
870         if (!ccw)
871                 return;
872
873         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
874         if (!config_area)
875                 goto out_free;
876
877         /* Make sure we don't overwrite fields. */
878         if (vcdev->config_ready < offset)
879                 virtio_ccw_get_config(vdev, 0, NULL, offset);
880         memcpy(&vcdev->config[offset], buf, len);
881         /* Write the config area to the host. */
882         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
883         ccw->cmd_code = CCW_CMD_WRITE_CONF;
884         ccw->flags = 0;
885         ccw->count = offset + len;
886         ccw->cda = (__u32)(unsigned long)config_area;
887         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
888
889 out_free:
890         kfree(config_area);
891         kfree(ccw);
892 }
893
894 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
895 {
896         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
897         u8 old_status = *vcdev->status;
898         struct ccw1 *ccw;
899
900         if (vcdev->revision < 1)
901                 return *vcdev->status;
902
903         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
904         if (!ccw)
905                 return old_status;
906
907         ccw->cmd_code = CCW_CMD_READ_STATUS;
908         ccw->flags = 0;
909         ccw->count = sizeof(*vcdev->status);
910         ccw->cda = (__u32)(unsigned long)vcdev->status;
911         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
912 /*
913  * If the channel program failed (should only happen if the device
914  * was hotunplugged, and then we clean up via the machine check
915  * handler anyway), vcdev->status was not overwritten and we just
916  * return the old status, which is fine.
917 */
918         kfree(ccw);
919
920         return *vcdev->status;
921 }
922
923 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
924 {
925         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
926         u8 old_status = *vcdev->status;
927         struct ccw1 *ccw;
928         int ret;
929
930         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
931         if (!ccw)
932                 return;
933
934         /* Write the status to the host. */
935         *vcdev->status = status;
936         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
937         ccw->flags = 0;
938         ccw->count = sizeof(status);
939         ccw->cda = (__u32)(unsigned long)vcdev->status;
940         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
941         /* Write failed? We assume status is unchanged. */
942         if (ret)
943                 *vcdev->status = old_status;
944         kfree(ccw);
945 }
946
947 static const struct virtio_config_ops virtio_ccw_config_ops = {
948         .get_features = virtio_ccw_get_features,
949         .finalize_features = virtio_ccw_finalize_features,
950         .get = virtio_ccw_get_config,
951         .set = virtio_ccw_set_config,
952         .get_status = virtio_ccw_get_status,
953         .set_status = virtio_ccw_set_status,
954         .reset = virtio_ccw_reset,
955         .find_vqs = virtio_ccw_find_vqs,
956         .del_vqs = virtio_ccw_del_vqs,
957 };
958
959
960 /*
961  * ccw bus driver related functions
962  */
963
964 static void virtio_ccw_release_dev(struct device *_d)
965 {
966         struct virtio_device *dev = dev_to_virtio(_d);
967         struct virtio_ccw_device *vcdev = to_vc_device(dev);
968
969         kfree(vcdev->status);
970         kfree(vcdev->config_block);
971         kfree(vcdev);
972 }
973
974 static int irb_is_error(struct irb *irb)
975 {
976         if (scsw_cstat(&irb->scsw) != 0)
977                 return 1;
978         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
979                 return 1;
980         if (scsw_cc(&irb->scsw) != 0)
981                 return 1;
982         return 0;
983 }
984
985 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
986                                               int index)
987 {
988         struct virtio_ccw_vq_info *info;
989         unsigned long flags;
990         struct virtqueue *vq;
991
992         vq = NULL;
993         spin_lock_irqsave(&vcdev->lock, flags);
994         list_for_each_entry(info, &vcdev->virtqueues, node) {
995                 if (info->vq->index == index) {
996                         vq = info->vq;
997                         break;
998                 }
999         }
1000         spin_unlock_irqrestore(&vcdev->lock, flags);
1001         return vq;
1002 }
1003
1004 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1005                                       __u32 activity)
1006 {
1007         if (vcdev->curr_io & activity) {
1008                 switch (activity) {
1009                 case VIRTIO_CCW_DOING_READ_FEAT:
1010                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1011                 case VIRTIO_CCW_DOING_READ_CONFIG:
1012                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1013                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1014                 case VIRTIO_CCW_DOING_READ_STATUS:
1015                 case VIRTIO_CCW_DOING_SET_VQ:
1016                 case VIRTIO_CCW_DOING_SET_IND:
1017                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1018                 case VIRTIO_CCW_DOING_RESET:
1019                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1020                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1021                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1022                         vcdev->curr_io &= ~activity;
1023                         wake_up(&vcdev->wait_q);
1024                         break;
1025                 default:
1026                         /* don't know what to do... */
1027                         dev_warn(&vcdev->cdev->dev,
1028                                  "Suspicious activity '%08x'\n", activity);
1029                         WARN_ON(1);
1030                         break;
1031                 }
1032         }
1033 }
1034
1035 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1036                                    unsigned long intparm,
1037                                    struct irb *irb)
1038 {
1039         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1040         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1041         int i;
1042         struct virtqueue *vq;
1043
1044         if (!vcdev)
1045                 return;
1046         if (IS_ERR(irb)) {
1047                 vcdev->err = PTR_ERR(irb);
1048                 virtio_ccw_check_activity(vcdev, activity);
1049                 /* Don't poke around indicators, something's wrong. */
1050                 return;
1051         }
1052         /* Check if it's a notification from the host. */
1053         if ((intparm == 0) &&
1054             (scsw_stctl(&irb->scsw) ==
1055              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1056                 /* OK */
1057         }
1058         if (irb_is_error(irb)) {
1059                 /* Command reject? */
1060                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1061                     (irb->ecw[0] & SNS0_CMD_REJECT))
1062                         vcdev->err = -EOPNOTSUPP;
1063                 else
1064                         /* Map everything else to -EIO. */
1065                         vcdev->err = -EIO;
1066         }
1067         virtio_ccw_check_activity(vcdev, activity);
1068         for_each_set_bit(i, &vcdev->indicators,
1069                          sizeof(vcdev->indicators) * BITS_PER_BYTE) {
1070                 /* The bit clear must happen before the vring kick. */
1071                 clear_bit(i, &vcdev->indicators);
1072                 barrier();
1073                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1074                 vring_interrupt(0, vq);
1075         }
1076         if (test_bit(0, &vcdev->indicators2)) {
1077                 virtio_config_changed(&vcdev->vdev);
1078                 clear_bit(0, &vcdev->indicators2);
1079         }
1080 }
1081
1082 /*
1083  * We usually want to autoonline all devices, but give the admin
1084  * a way to exempt devices from this.
1085  */
1086 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1087                      (8*sizeof(long)))
1088 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1089
1090 static char *no_auto = "";
1091
1092 module_param(no_auto, charp, 0444);
1093 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1094
1095 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1096 {
1097         struct ccw_dev_id id;
1098
1099         ccw_device_get_id(cdev, &id);
1100         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1101                 return 0;
1102         return 1;
1103 }
1104
1105 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1106 {
1107         struct ccw_device *cdev = data;
1108         int ret;
1109
1110         ret = ccw_device_set_online(cdev);
1111         if (ret)
1112                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1113 }
1114
1115 static int virtio_ccw_probe(struct ccw_device *cdev)
1116 {
1117         cdev->handler = virtio_ccw_int_handler;
1118
1119         if (virtio_ccw_check_autoonline(cdev))
1120                 async_schedule(virtio_ccw_auto_online, cdev);
1121         return 0;
1122 }
1123
1124 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1125 {
1126         unsigned long flags;
1127         struct virtio_ccw_device *vcdev;
1128
1129         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1130         vcdev = dev_get_drvdata(&cdev->dev);
1131         if (!vcdev || vcdev->going_away) {
1132                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1133                 return NULL;
1134         }
1135         vcdev->going_away = true;
1136         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1137         return vcdev;
1138 }
1139
1140 static void virtio_ccw_remove(struct ccw_device *cdev)
1141 {
1142         unsigned long flags;
1143         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1144
1145         if (vcdev && cdev->online) {
1146                 if (vcdev->device_lost)
1147                         virtio_break_device(&vcdev->vdev);
1148                 unregister_virtio_device(&vcdev->vdev);
1149                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1150                 dev_set_drvdata(&cdev->dev, NULL);
1151                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1152         }
1153         cdev->handler = NULL;
1154 }
1155
1156 static int virtio_ccw_offline(struct ccw_device *cdev)
1157 {
1158         unsigned long flags;
1159         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1160
1161         if (!vcdev)
1162                 return 0;
1163         if (vcdev->device_lost)
1164                 virtio_break_device(&vcdev->vdev);
1165         unregister_virtio_device(&vcdev->vdev);
1166         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1167         dev_set_drvdata(&cdev->dev, NULL);
1168         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1169         return 0;
1170 }
1171
1172 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1173 {
1174         struct virtio_rev_info *rev;
1175         struct ccw1 *ccw;
1176         int ret;
1177
1178         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
1179         if (!ccw)
1180                 return -ENOMEM;
1181         rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
1182         if (!rev) {
1183                 kfree(ccw);
1184                 return -ENOMEM;
1185         }
1186
1187         /* Set transport revision */
1188         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1189         ccw->flags = 0;
1190         ccw->count = sizeof(*rev);
1191         ccw->cda = (__u32)(unsigned long)rev;
1192
1193         vcdev->revision = VIRTIO_CCW_REV_MAX;
1194         do {
1195                 rev->revision = vcdev->revision;
1196                 /* none of our supported revisions carry payload */
1197                 rev->length = 0;
1198                 ret = ccw_io_helper(vcdev, ccw,
1199                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1200                 if (ret == -EOPNOTSUPP) {
1201                         if (vcdev->revision == 0)
1202                                 /*
1203                                  * The host device does not support setting
1204                                  * the revision: let's operate it in legacy
1205                                  * mode.
1206                                  */
1207                                 ret = 0;
1208                         else
1209                                 vcdev->revision--;
1210                 }
1211         } while (ret == -EOPNOTSUPP);
1212
1213         kfree(ccw);
1214         kfree(rev);
1215         return ret;
1216 }
1217
1218 static int virtio_ccw_online(struct ccw_device *cdev)
1219 {
1220         int ret;
1221         struct virtio_ccw_device *vcdev;
1222         unsigned long flags;
1223
1224         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1225         if (!vcdev) {
1226                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1227                 ret = -ENOMEM;
1228                 goto out_free;
1229         }
1230         vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1231                                    GFP_DMA | GFP_KERNEL);
1232         if (!vcdev->config_block) {
1233                 ret = -ENOMEM;
1234                 goto out_free;
1235         }
1236         vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1237         if (!vcdev->status) {
1238                 ret = -ENOMEM;
1239                 goto out_free;
1240         }
1241
1242         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1243
1244         vcdev->vdev.dev.parent = &cdev->dev;
1245         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1246         vcdev->vdev.config = &virtio_ccw_config_ops;
1247         vcdev->cdev = cdev;
1248         init_waitqueue_head(&vcdev->wait_q);
1249         INIT_LIST_HEAD(&vcdev->virtqueues);
1250         spin_lock_init(&vcdev->lock);
1251
1252         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1253         dev_set_drvdata(&cdev->dev, vcdev);
1254         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1255         vcdev->vdev.id.vendor = cdev->id.cu_type;
1256         vcdev->vdev.id.device = cdev->id.cu_model;
1257
1258         ret = virtio_ccw_set_transport_rev(vcdev);
1259         if (ret)
1260                 goto out_free;
1261
1262         ret = register_virtio_device(&vcdev->vdev);
1263         if (ret) {
1264                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1265                          ret);
1266                 goto out_put;
1267         }
1268         return 0;
1269 out_put:
1270         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1271         dev_set_drvdata(&cdev->dev, NULL);
1272         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1273         put_device(&vcdev->vdev.dev);
1274         return ret;
1275 out_free:
1276         if (vcdev) {
1277                 kfree(vcdev->status);
1278                 kfree(vcdev->config_block);
1279         }
1280         kfree(vcdev);
1281         return ret;
1282 }
1283
1284 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1285 {
1286         int rc;
1287         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1288
1289         /*
1290          * Make sure vcdev is set
1291          * i.e. set_offline/remove callback not already running
1292          */
1293         if (!vcdev)
1294                 return NOTIFY_DONE;
1295
1296         switch (event) {
1297         case CIO_GONE:
1298                 vcdev->device_lost = true;
1299                 rc = NOTIFY_DONE;
1300                 break;
1301         default:
1302                 rc = NOTIFY_DONE;
1303                 break;
1304         }
1305         return rc;
1306 }
1307
1308 static struct ccw_device_id virtio_ids[] = {
1309         { CCW_DEVICE(0x3832, 0) },
1310         {},
1311 };
1312
1313 static struct ccw_driver virtio_ccw_driver = {
1314         .driver = {
1315                 .owner = THIS_MODULE,
1316                 .name = "virtio_ccw",
1317         },
1318         .ids = virtio_ids,
1319         .probe = virtio_ccw_probe,
1320         .remove = virtio_ccw_remove,
1321         .set_offline = virtio_ccw_offline,
1322         .set_online = virtio_ccw_online,
1323         .notify = virtio_ccw_cio_notify,
1324         .int_class = IRQIO_VIR,
1325 };
1326
1327 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1328                            int max_digit, int max_val)
1329 {
1330         int diff;
1331
1332         diff = 0;
1333         *val = 0;
1334
1335         while (diff <= max_digit) {
1336                 int value = hex_to_bin(**cp);
1337
1338                 if (value < 0)
1339                         break;
1340                 *val = *val * 16 + value;
1341                 (*cp)++;
1342                 diff++;
1343         }
1344
1345         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1346                 return 1;
1347
1348         return 0;
1349 }
1350
1351 static int __init parse_busid(char *str, unsigned int *cssid,
1352                               unsigned int *ssid, unsigned int *devno)
1353 {
1354         char *str_work;
1355         int rc, ret;
1356
1357         rc = 1;
1358
1359         if (*str == '\0')
1360                 goto out;
1361
1362         str_work = str;
1363         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1364         if (ret || (str_work[0] != '.'))
1365                 goto out;
1366         str_work++;
1367         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1368         if (ret || (str_work[0] != '.'))
1369                 goto out;
1370         str_work++;
1371         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1372         if (ret || (str_work[0] != '\0'))
1373                 goto out;
1374
1375         rc = 0;
1376 out:
1377         return rc;
1378 }
1379
1380 static void __init no_auto_parse(void)
1381 {
1382         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1383         char *parm, *str;
1384         int rc;
1385
1386         str = no_auto;
1387         while ((parm = strsep(&str, ","))) {
1388                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1389                                  &from_ssid, &from);
1390                 if (rc)
1391                         continue;
1392                 if (parm != NULL) {
1393                         rc = parse_busid(parm, &to_cssid,
1394                                          &to_ssid, &to);
1395                         if ((from_ssid > to_ssid) ||
1396                             ((from_ssid == to_ssid) && (from > to)))
1397                                 rc = -EINVAL;
1398                 } else {
1399                         to_cssid = from_cssid;
1400                         to_ssid = from_ssid;
1401                         to = from;
1402                 }
1403                 if (rc)
1404                         continue;
1405                 while ((from_ssid < to_ssid) ||
1406                        ((from_ssid == to_ssid) && (from <= to))) {
1407                         set_bit(from, devs_no_auto[from_ssid]);
1408                         from++;
1409                         if (from > __MAX_SUBCHANNEL) {
1410                                 from_ssid++;
1411                                 from = 0;
1412                         }
1413                 }
1414         }
1415 }
1416
1417 static int __init virtio_ccw_init(void)
1418 {
1419         /* parse no_auto string before we do anything further */
1420         no_auto_parse();
1421         return ccw_driver_register(&virtio_ccw_driver);
1422 }
1423 device_initcall(virtio_ccw_init);