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