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