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