drivers/s390/virtio/virtio_ccw.c

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